U.S. patent application number 16/055725 was filed with the patent office on 2019-02-28 for image forming apparatus and image forming method.
The applicant listed for this patent is KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA. Invention is credited to Yayoi DOI.
Application Number | 20190068814 16/055725 |
Document ID | / |
Family ID | 63014160 |
Filed Date | 2019-02-28 |
United States Patent
Application |
20190068814 |
Kind Code |
A1 |
DOI; Yayoi |
February 28, 2019 |
IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD
Abstract
A sheet processing apparatus according to an embodiment includes
an image reading unit that reads an image of a sheet. A sheet
discharge tray receives a sheet read by the image reading unit. A
measurement unit measures a total weight of sheets on the sheet
discharge tray. A read counter counts a number of all sheets read
by the image reading unit. The read counter stores the number of
the currently read sheet in association with the measured total
weight of the sheets on the sheet discharge tray. A measured value
comparison unit compares the current measured weight of the sheets
and a stored measured weight stored in association with the number
of the read sheet immediately preceding the currently read sheet. A
dropped page identification unit identifies, by page number, one or
more sheets dropped from the sheet discharge unit based on the
comparison result.
Inventors: |
DOI; Yayoi; (Mishima
Shizuoka, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOSHIBA
TOSHIBA TEC KABUSHIKI KAISHA |
Tokyo
Tokyo |
|
JP
JP |
|
|
Family ID: |
63014160 |
Appl. No.: |
16/055725 |
Filed: |
August 6, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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15685841 |
Aug 24, 2017 |
10044889 |
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16055725 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04N 1/00068 20130101;
B65H 7/20 20130101; B65H 2301/4212 20130101; B65H 7/04 20130101;
B65H 2801/06 20130101; B65H 43/06 20130101; B65H 31/02 20130101;
B65H 2515/10 20130101; G03G 2221/1823 20130101; B65H 2511/30
20130101; H04N 1/00726 20130101; H04N 2201/0094 20130101; B65H
2515/10 20130101; B65H 2220/01 20130101; B65H 2511/30 20130101;
B65H 2220/01 20130101 |
International
Class: |
H04N 1/00 20060101
H04N001/00; B65H 7/04 20060101 B65H007/04 |
Claims
1. A sheet processing apparatus comprising: an image reading unit
configured to read an image of a sheet; a sheet discharge tray
configured to receive a sheet read by the image reading unit; a
measurement unit configured to measure a total weight of one or
more sheets on the sheet discharge tray; a storage unit; and a
processor programmed to function as: a read counter configured to,
for each currently read sheet, count a number of all sheets,
including the currently read sheet, read by the image reading unit
in a scanning job, and store in the storage unit the number of the
currently read sheet in association with the measured total weight
of the sheets, including the currently read sheet by the image
reading unit, on the sheet discharge tray, a measured value
comparison unit configured to compare the measured total weight of
the sheets on the sheet discharge tray and a stored measured weight
stored in association with the number of the read sheet immediately
preceding the currently read sheet, and a dropped page
identification unit configured to identify, by page number, one or
more sheets dropped from the sheet discharge unit based on the
comparison result.
2. The apparatus according to claim 1, wherein, if the measured
total weight is determined to be less than or equal to the stored
measured weight, the dropped page identification unit identifies at
least the currently read sheet as the dropped sheet.
3. The apparatus according to claim 2, wherein: if the measured
total weight is determined to be equal to the stored measured
weight, the dropped page identification unit identifies the
currently read sheet as the dropped sheet, and if the compared
measured total weight is determined to be less than the stored
measured weight, the dropped page identification unit identifies at
least the currently read sheet and the read sheet immediately
preceding the currently read sheet as the dropped sheets.
4. The apparatus according to claim 3, wherein, if the compared
measured total weight is determined to be less than the stored
measured weight, the measured value comparison unit compares the
measured total weight and a stored measured weight stored in
association with the number of a next preceding read sheet that was
read before the immediately preceding read sheet, and if the
compared measured total weight is determined to be less than the
stored measured weight stored in association with the number of the
next preceding read sheet, the dropped page identification unit
identifies the currently read sheet, the read sheet immediately
preceding the current read sheet, and the next preceding read sheet
as the dropped sheets.
5. The apparatus according to claim 2, further comprising: a
display, wherein the processor is configured to control the display
to display a dropped page screen identifying the dropped sheets
identified by the dropped page identification unit, if all the
sheets in the scanning job are read and if the dropped page
identification unit identifies at least one dropped sheet.
6. The apparatus according to claim 1, wherein, if the measured
total weight is determined to be greater than the stored measured
weight, the dropped page identification unit does not identify a
dropped sheet.
7. The apparatus according to claim 6, further comprising: a
display, wherein the processor is configured to control the display
to display a read finish screen indicating there were no dropped
sheets in the scanning job, if all the sheets in the scanning job
are read and if the dropped page identification unit does not
identify a dropped sheet.
8. A sheet processing apparatus comprising: a sheet discharge tray
configured to receive discharged sheets; a measurement unit
configured to measure a total weight of one or more sheets on the
sheet discharge tray; a storage unit; and a processor programmed to
function as: a read counter configured to, for each currently
discharged sheet, count a number of all sheets on the sheet
discharge tray, and store in the storage unit the number of the
currently discharged sheet in association with the measured total
weight of the sheets, including the currently discharged sheet, on
the sheet discharge tray, a measured value comparison unit
configured to compare the measured total weight of the sheets on
the sheet discharge tray and a stored measured weight stored in
association with the number of the sheet discharged to the sheet
discharge tray immediately preceding the currently discharged
sheet, and a dropped page identification unit configured to
identify, by page number, one or more sheets dropped from the sheet
discharge unit based on the comparison result.
9. The apparatus according to claim 8, wherein, if the measured
total weight is determined to be less than or equal to the stored
measured weight, the dropped page identification unit identifies at
least the currently discharged sheet as the dropped sheet.
10. The apparatus according to claim 9, wherein: if the measured
total weight is determined to be the same as the stored measured
weight, the dropped page identification unit identifies the
currently discharged sheet as the dropped sheet, and if the
measured total weight is determined to be less than the stored
measured weight, the dropped page identification unit identifies at
least the currently discharged sheet and the sheet discharged
immediately preceding the currently discharged sheet as the dropped
sheets.
11. The apparatus according to claim 10, wherein, if the measured
total weight is determined to be less than the stored measured
weight, the measured value comparison unit compares the measured
total weight and a stored measured weight stored in association
with the number of the next preceding discharged sheet that was
read before the immediately preceding read sheet, and if the
compared current measured weight is determined to be less than the
stored measured weight stored in association with the number of the
next preceding read sheet, the dropped page identification unit
identifies the currently discharged sheet, the sheet discharged
immediately preceding the current read sheet, and the next
preceding discharged sheet as the dropped sheets.
12. The apparatus according to claim 9, further comprising: a
display, wherein the processor is configured to control the display
to display a dropped page screen identifying the dropped sheets
identified by the dropped page identification unit, if discharging
of the sheets is complete and if the dropped page identification
unit identifies at least one dropped sheet.
13. The apparatus according to claim 8, wherein, if the measured
total weight is determined to be greater than the stored measured
weight, the dropped page identification unit does not identify a
dropped sheet.
14. The apparatus according to claim 13, further comprising: a
display, wherein the processor is configured to control the display
to display a process finish screen indicating there were no dropped
sheets, if discharging of the sheets is complete and if the dropped
page identification unit does not identify a dropped sheet.
15. The apparatus according to claim 8, wherein the sheets are
discharged to the sheet discharge tray from one of a sheet reading
apparatus and an image forming apparatus.
16. A sheet processing method comprising: receiving, one by one,
sheets on a sheet discharge tray; for each currently discharged
sheet: measuring a total weight of one or more sheets on the sheet
discharge tray, counting a number of all sheets on the sheet
discharge tray, storing the number of the currently discharged
sheet in association with the measured total weight of the sheets,
including the currently discharged sheet, on the sheet discharge
tray, and comparing the measured total weight of the sheets on the
sheet discharge tray and a stored measured weight stored in
association with the number of the sheet discharged to the sheet
discharge tray immediately preceding the currently discharged
sheet; and identifying, by page number, any sheets dropped from the
sheet discharge unit based on the comparison result.
17. The method according to claim 16, wherein, if the measured
total weight is determined to be less than or equal to the stored
measured weight, at least the currently discharged sheet is
identified as the dropped sheet.
18. The method according to claim 17, wherein: if the measured
total weight is determined to be the same as the stored measured
weight, the currently discharged sheet is identified as the dropped
sheet, and if the compared measured total weight is determined to
be less than the stored measured weight, at least the currently
discharged sheet and the sheet discharged immediately preceding the
currently discharged sheet are identified as the dropped
sheets.
19. The method according to claim 16, further comprising:
displaying one of: a dropped page screen identifying the dropped
sheets identified by the dropped page identification unit, if
discharging of the sheets is complete and if at least one dropped
sheet is identified, and a process finish screen indicating there
were no dropped sheets, if discharging of the sheets is complete
and if no dropped sheets are identified.
20. The method according to claim 16, wherein the sheets are
discharged to the sheet discharge tray from one of a sheet reading
apparatus and an image forming apparatus.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent
application Ser. No. 15/685,841, filed on Aug. 24, 2017, the entire
contents of each of which are incorporated herein by reference.
FIELD
[0002] Embodiments described herein relate generally to an image
forming apparatus and an image forming method.
BACKGROUND
[0003] In an image forming apparatus such as machine multi-function
peripheral (MFP), a discharge speed of a sheet increases as a
result of increased scanning speed. Thus, after discharging, the
sheets may be uneven or dropped onto a floor without being
contained in the sheet discharge tray. Therefore, when a large
amount of documents are scanned, a user must take time to align the
sheets. In addition, when one or more sheets drop, it may be
difficult to return the sheets to an original page order. There is
also a case where sometimes a part of the sheet is lost because a
user did not notice the drop.
[0004] In order to prevent the sheet discharged after scanning from
dropping, a shape of a sheet discharge tray may be altered.
However, although it is possible to suppress dropping of the sheet,
the problem related to dropping of the sheet after the scanning
cannot be satisfactorily solved.
DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is an external view showing an example configuration
of an image forming apparatus according to an embodiment.
[0006] FIG. 2 is a block diagram indicating an example functional
configuration of the image forming apparatus.
[0007] FIG. 3 is a flowchart indicating an example sequence of
operations of an image read process.
[0008] FIG. 4 is a flowchart indicating an example sequence of
operations of an image read process.
[0009] FIG. 5 is a graph indicating a change of a measuring value
when scanning is normally progressed.
[0010] FIG. 6 is an example of an image displayed on a display when
the scanning is normally finished.
[0011] FIG. 7 is a diagram showing a change in weight when a sheet
is dropped from a sheet discharge tray during the scanning.
[0012] FIG. 8 is an example of an image displayed on a display
after scanning when the sheet is dropped during the scanning.
DETAILED DESCRIPTION
[0013] A sheet processing apparatus according to an embodiment
includes an image reading unit that reads an image of a sheet. A
sheet discharge tray receives a sheet read by the image reading
unit. A measurement unit measures a total weight of one or more
sheets on the sheet discharge tray. A read counter counts, for each
currently read sheet, a number of all sheets, including the
currently read sheet, read by the image reading unit in a scanning
job. The read counter stores in a storage unit the number of the
currently read sheet in association with the measured total weight
of the sheets, including the currently read by the image reading
unit, on the sheet discharge tray. A measured value comparison unit
compares the current measured weight of the sheets on the sheet
discharge tray and a stored measured weight stored in association
with the number of the read sheet immediately preceding the
currently read sheet. A dropped page identification unit
identifies, by page number, one or more sheets dropped from the
sheet discharge unit based on the comparison result.
[0014] FIG. 1 is an external view showing an example configuration
of image forming apparatus 100 according to the embodiment. For
example, image forming apparatus 100 is an MFP. The image forming
apparatus 100 includes a display 110, a control panel 120, a
printer 130, a sheet accommodation unit 140 (e.g., a sheet tray), a
sheet discharge unit 160, and an image reading unit 200. In one
embodiment, an image reading unit 200 is a scanner, e.g., a CCD
image sensor, CMOS image sensor, or contact image sensor, and the
sheet discharge unit 160 is a tray for receiving the sheet read by
the image reading unit 200. The sheet discharge unit 160 includes a
weight sensor to measure the weight of sheets. The weight sensor
may be load cell type or electrostatic capacitance type.
[0015] The image forming apparatus 100 forms an image on a sheet by
using, for example, a developer such as a toner. The sheet may be,
for example, a paper or a label paper. The sheet may be anything as
long as the image forming apparatus 100 can form an image on a
surface of the sheet.
[0016] The display 110 is an image display device such as a liquid
crystal display and an organic electro luminescence (EL) display.
The display 110 displays various pieces of information relating to
the image forming apparatus 100. The display 110 is an example of a
display unit.
[0017] The control panel 120 includes a plurality of buttons. The
control panel 120 receives a user's operation. The control panel
120 outputs a signal according to an operation performed by the
user with respect to a control unit of the image forming apparatus
100. The display 110 and the control panel 120 may be provided
together as an integrated touch panel.
[0018] The printer 130 forms an image on the sheet based on image
information generated by the image reading unit 200 or image
information received through a communication path. For example, the
printer 130 forms an image by the following process. An image
forming unit of the printer 130 forms an electrostatic latent image
on a photosensitive drum based on the image information. The image
forming unit of the printer 130 forms a visible image by applying
the developer to the electrostatic latent image. As a specific
example of the developer, toner may be used. A transfer unit of the
printer 130 transfers the visible image onto the sheet. A fixing
unit of the printer 130 fixes the visible image on the sheet by
applying heat and pressure with respect to the sheet. The sheet on
which the image is formed may be the sheet accommodated in the
sheet accommodation unit 140, or may be a manually fed sheet.
[0019] The sheet accommodation unit 140 accommodates sheets used
for image formation in the printer 130.
[0020] The sheet discharge unit 160 discharges the sheet from which
the image is read by the image reading unit 200.
[0021] The image reading unit 200 reads the image information of a
read target based on brightness and darkness of light. The image
reading unit 200 records the read image information. The recorded
image information may be transmitted to another information
processing apparatus through a network. The recorded image
information may be used to form an image on the sheet by the
printer 130.
[0022] FIG. 2 is a block diagram indicating an example functional
configuration of the image forming apparatus of the embodiment. The
image forming apparatus 100 includes a measured value storage unit
101, a dropped page storage unit 102, a measurement unit 103 (e.g.,
a weight sensor), a display 110, a control panel 120, a printer
130, a control unit 150, and the image reading unit 200.
[0023] The measured value storage unit 101 may be included in a
storage device such as a magnetic hard disk device or a
semiconductor storage device. The measured value storage unit 101
associates the number of the current read sheet with a
corresponding measured value of the 1.sup.st through current sheets
which have been read during the scanning operation, and stores an
associated result. The measured value storage unit 101 stores each
of the read sheet numbers and the corresponding measured value.
Whenever a sheet is read, the measured value storage unit 101
stores the number of the read sheet and the corresponding measured
value. Hereinafter, the measured values stored in the measured
value storage unit 101 are each referred to as a "stored measured
value." Similarly, the measured value corresponding to the
currently read sheet is referred to as a "currently measured
value."
[0024] The number of the read sheet corresponds to the total number
of sheets which have so far been read by the image reading unit
200. The number of read sheets is counted by a read counter 151.
The measured value is a cumulative weight of the sheets that are
discharged to a sheet discharge tray (not shown). The measured
value is measured by the measurement unit 103 each time one of the
sheets is read. The scanned sheet is discharged to the sheet
discharge tray. The sheet discharge tray is an example of the sheet
discharge unit.
[0025] The dropped page storage unit 102 may be included in the
storage device such as the magnetic hard disk device and the
semiconductor storage device. The dropped page storage unit 102
stores a page number of the sheet that is dropped from the sheet
discharge tray from among the sheets discharged after reading the
image. When multiple sheets drop, the dropped page storage unit 102
stores a plurality of page numbers.
[0026] The measurement unit 103 may be a weight measuring device
such as a weight sensor. The measurement unit 103 measures a weight
on the sheet discharge tray. The measurement unit 103 is attached
to the sheet discharge tray of the image forming apparatus 100. The
read counter 151 stores the measured value (i.e., the weight)
measured by the measurement unit 103 in the measured value storage
unit 101 in association with the corresponding (ordinal) number of
the read sheet.
[0027] The control unit 150 controls an operation of each unit of
the image forming apparatus 100. For example, the control unit 150
is operated by a device in which a central processing unit (CPU)
and a random access memory (RAM) are included. In one embodiment,
the control unit 150 is programmed to function as the read counter
151, a measured value comparison unit 152, and a dropped page
identification unit 153. The flow of the programs executed by the
control unit 150 corresponding to the read counter 151, the
measured value comparison unit 152, and the dropped page
identification unit 153 is further described below.
[0028] The read counter 151 counts the number of sheets read by the
image reading unit 200 during the scanning. The number of read
sheets indicates a page number (i.e., the ordinal number) of the
sheet. The read counter 151 associates the number of read sheets
with the corresponding measured value one by one, and stores the
associated result in the measured value storage unit 101. In
addition, when it is determined that one of the read sheets drops
from the sheet discharge tray, the read counter 151 stores the
(ordinal) number of the dropped sheet(s) in the dropped page
storage unit 102. The read counter 151 outputs the number of the
read sheet to the measured value comparison unit 152 or the dropped
page identification unit 153 according to a request from the
measured value comparison unit 152 or the dropped page
identification unit 153.
[0029] The measured value comparison unit 152 compares the stored
and current measured values. Specifically, the measured value
comparison unit 152 compares the stored measured value associated
with the number of the previously read sheet with the current
measured value. As a comparison result, when the current measured
value is not greater than the stored measured value corresponding
to the previously read sheet, the measured value comparison unit
152 determines that the read sheet is dropped. Furthermore, as the
comparison result, when the current measured value is smaller than
the stored measured value corresponding to the previously read
sheet, it is determined that the sheet already placed on the sheet
discharge tray and the currently read sheet are both dropped
together. In addition, when the current measured value is smaller
than the stored measured value corresponding to the previously read
sheet, the measured value comparison unit 152 compares the stored
measured value of the number of the next previously read sheet with
the currently measured value. The measured value comparison unit
152 obtains the stored measured value of the number of the next
previously read sheet from the measured value storage unit 101 and
compares it to the current measured value. The process--comparing
the current measured value to the stored measured value of the next
previous read sheet--repeats until the current measured value and
the stored measured value coincide with each other.
[0030] The dropped page identification unit 153 identifies one or
more dropped pages indicating a page number of the dropped sheet(s)
among the sheets placed on the sheet discharge tray. Specifically,
when it is determined that a sheet which is already placed on the
sheet discharge tray and the read sheet are dropped together, the
dropped page identification unit 153 determines the number of
dropped sheets. The number of dropped sheets indicates the number
of sheets dropped together, including the read sheet and dropped
sheets that were already placed on the sheet discharge tray. The
dropped page identification unit 153 determines a value by
subtracting the number of dropped sheets from the number of the
currently read sheet as the page number of the dropped sheet. The
dropped page identification unit 153 stores the page number(s) of
the dropped sheet in the dropped page storage unit 102. The dropped
page identification unit 153 counts the number of dropped sheets
until the current measured value and the stored measured value
coincide with each other, in incremental steps similar to that
described above with respect to the measured value comparison unit
152. Accordingly, the page number of the dropped sheet is stored in
the dropped page storage unit 102. The number of dropped sheets is
a counted value.
[0031] FIG. 3 and FIG. 4 are flowcharts indicating an example
sequence of operations of an image read process in the image
forming apparatus of the embodiment. The sheet is disposed in a
document feeder (DF) of the image reading unit 200 (Act 101). The
control panel 120 receives a scan instruction from a user (Act
102). The read counter 151 sets the number of read sheets to 0 (Act
103). The dropped page identification unit 153 sets the number of
dropped sheets to 0 (Act 104).
[0032] The image reading unit 200 reads the sheet disposed in the
DF (Act 105). Whenever a sheet is read, the read counter 151
increments the number of read sheets by one (Act 106). Whenever one
sheet is read and the read sheet is discharged to the sheet
discharge tray, the measurement unit 103 determines the current
measured weight value (e.g., weight) of all sheets on the sheet
discharge tray (Act 107). The read counter 151 associates the
number of read sheets counted in Act 106 with the measured value
measured in Act 107, and stores the associated result in the
measured value storage unit 101 (Act 108). Specifically, for
example, when the image reading unit 200 reads the second sheet,
the read counter 151 associates a value of the total number of the
read sheets (in this case, two) with a measured value (e.g.,
weight) when the second sheet is discharged onto the sheet
discharge tray, and stores the associated result in the measured
value storage unit 101. The measured value comparison unit 152
compares the current measured value measured in Act 107 and the
stored measured value associated with the number of the previously
read sheet, i.e., the number of the currently read sheet minus one
(Act 109).
[0033] The measured value comparison unit 152 determines whether or
not the measured value is increased (Act 110). When it is
determined that the measured value is increased (Act 110: YES), the
process transitions to Act 117. When it is determined that the
measured value is not increased (Act 110: NO), the read counter 151
stores the number of the read sheets in the dropped page storage
unit 102 (Act 111). That is, in Act 111, since the measured value
is not increased, it is determined that the read sheet is dropped,
the number of read sheets (which is the page number of the
currently read sheet) is stored in the dropped page storage unit
102.
[0034] The measured value comparison unit 152 determines whether or
not the measured value is decreased (Act 112). When it is
determined that the measured value is decreased (Act 112: NO), the
process transitions to Act 117. When it is determined that the
measured value is decreased (Act 112: YES), the dropped page
identification unit 153 counts the number of dropped sheets up by
one (Act 113). The dropped page identification unit 153 stores the
page number of the dropped sheet in the dropped page storage unit
102 (Act 114).
[0035] The measured value comparison unit 152 subtracts the number
of dropped sheets from the number of read sheets stored in the
measured value storage unit 101. The measured value comparison unit
152 identifies the number of the read sheet(s) which coincides with
the subtracted value. The stored measured value corresponding to
the identified number of read sheets and the current measured value
are compared with each other (Act 115).
[0036] The measured value comparison unit 152 determines whether or
not the stored measured value and the current measured value
coincide with each other (Act 116). When the measured values do not
coincide with each other (Act 116: NO), the process transitions to
Act 113. In other words, the measured value comparison unit 152
compares the current measured value with preceding stored measured
values, one by one in order from the immediately preceding stored
measured value, to the previously preceding (e.g., the "next"
preceding) stored measured value, until the current measured value
coincides with one of the preceding stored measured values.
[0037] When the measured values coincide with each other (Act 116:
YES), the image reading unit 200 determines whether or not reading
of the sheet is finished (Act 117). When the reading of the sheet
is not finished (Act 117: NO), the process transitions to Act
104.
[0038] When the reading of the sheet is finished (Act 118: YES),
the control unit 150 determines whether or not a page number of a
dropped sheet is stored in the dropped page storage unit 102 (Act
118). When at least one page number of a dropped sheet is stored
(Act 118: YES), the display 110 displays a dropped page screen
including the page number of the dropped sheet (Act 119). When a
page number of a dropped sheet is not stored (Act 118: NO), the
display 110 displays a reading finished screen (Act 120).
[0039] FIG. 5 is a graph indicating a change of the measured value
as scanning is normally progressed in the embodiment. The graph of
FIG. 5 includes a region 301, a region 302, a region 303, and a
region 304. The region 301 indicates an item name on a horizontal
axis of the graph. According to the region 301, the item name is
the "number of read sheets (sheets)". The "number of read sheets
(sheets)" indicates the number of read sheets counted by the read
counter 151. The "number of read sheets (sheets)" increases in a
direction indicated by an arrow. The region 302 indicates an item
name on a vertical axis of the graph. According to the region 302,
the item name is a "measured value [mg]". The "measured value [mg]"
indicates a measured value measured by the measurement unit 103.
The "measured value [mg]" increases in the direction indicated by
an arrow. The region 303 indicates increments of the number of
scanned sheets. The region 304 is a line indicating a relationship
between the number of read sheets (sheets) and the corresponding
measured value [mg]. According to the region 304, when image
reading normally progresses, as the number of read sheets (sheets)
is increased, the measured value [mg] is also increased.
[0040] FIG. 6 is a diagram indicating a specific example of the
reading finished screen displayed on a display when the scanning of
the embodiment is normally finished. A region 400 indicates an
image displayed on the display 110. The region 400 includes a
region 401 and a region 402. The number of read sheets scanned by
the image reading unit 200 is displayed on the region 401. For the
number of read sheets, a value counted by the read counter 151 is
used. According to the region 401, it is understood that xx sheets
are read. The number of sheets dropped from the sheet discharge
tray during the scanning is displayed on the region 402. For the
number of sheets, the number of the dropped pages stored in the
dropped page storage unit 102 is used. According to the region 402,
it is understood that there are no sheets dropped from the sheet
discharge tray.
[0041] FIG. 7 is a diagram showing a change in weight when a sheet
drops from a sheet discharge tray of the embodiment during the
scanning. A graph of FIG. 7 includes the region 301, the region
302, the region 303, and a region 304a. Since the region 301, the
region 302, and the region 303 indicate the same content as those
of the FIG. 5, the description is omitted. The region 304a is a
line indicating a relationship between the number of read sheets
(sheets) and the corresponding measured value [mg]. The region 304a
includes a region 304b and a region 304c.
[0042] The region 304b indicates a change of weight when the read
sheet is dropped from the sheet discharge tray. Specifically, the
region 304b indicates reading of seventh and eighth sheets in the
number of read sheets. In the region 304b, although the number of
read sheets (sheets) is increased, there is no change in the
measured value [mg]. According to, it is determined that the read
sheet is dropped from the sheet discharge tray. In addition,
according to the number of sheets scanned in the region 303, it is
understood that the dropped sheet is the eighth page. The region
304c indicates a change of weight when a sheet already on the sheet
discharge tray is also dropped together with the read sheet.
Specifically, the region 304c indicates the (n-2)th, (n-1)th, and
nth read sheets in the number of read sheets. In the region 304c,
although the number of read sheets in the (n-1)th and nth read
sheets in the number of read sheets is increased, the measured
value [mg] is decreased. Accordingly, it is determined that the
sheet already on the sheet discharge tray is dropped from the sheet
discharge tray together with the read sheet. According to the
region 304c, since the measured value after reading the nth read
sheet is the same as the measured value after reading the (n-2)th
read sheet, it is understood that the nth and (n-1)th sheets are
dropped.
[0043] FIG. 8 is a diagram showing one specific example the dropped
page screen displayed on a display after scanning when at least one
sheet is dropped during the scanning of the embodiment. A region
400a indicates an image displayed on the display 110. The region
400a includes the region 401, a region 402a, and a region 403.
Since the region 401 and the region 402a indicate the same content
as those of FIG. 6, the description is omitted. The page of the
sheet(s) dropped during the scanning is indicated on the region
403. The page of the dropped sheet is the dropped page stored in
the dropped page storage unit 102.
[0044] By adopting such a configuration, the measured value
comparison unit 152 determines whether or not the read sheet is
dropped from the sheet discharge tray by comparing the current
measured value measured by the measurement unit 103 and the
previous measured value stored in the measured value storage unit.
According to a comparison result, the dropped page identification
unit 153 identifies the number of dropped sheets, and stores the
number of the dropped page in the dropped page storage unit 102.
After finishing the scanning, the dropped page that is stored is
displayed on the display 110. Accordingly, by looking at the
display 110, users can identify the dropped page during the
scanning.
[0045] In the above-described embodiment, it is described in detail
that the sheet is dropped from the sheet discharge tray during the
scanning. However, for other functions such as copy and print, the
measurement unit 103 may be attached to the sheet discharge tray on
which the sheet after forming an image is discharged. According to
such a configuration, for the sheet discharge tray to which the
sheet on which an image is formed is discharged, it is possible to
identify a dropped sheet. Accordingly, users can identify the page
dropped during the image formation, and can prevent the sheet from
being lost.
[0046] The dropped page identification unit 153 may be configured
to count the total number of dropped pages, in addition to counting
the number of sheets dropped after already being placed on the
sheet discharge tray, together with the read sheet. According to
such a configuration, users can quickly identify the number of the
dropped sheets, and can prevent the sheet from being lost.
[0047] While certain embodiments have been described these
embodiments have been presented by way of example only, and are not
intended to limit the scope of the inventions. Indeed, the novel
embodiments described herein may be embodied in a variety of other
forms: furthermore various omissions, substitutions and changes in
the form of the embodiments described herein may be made without
departing from the spirit of the inventions. The accompanying
claims and their equivalents are intended to cover such forms or
modifications as would fall within the scope and spirit of the
invention.
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