U.S. patent application number 12/210250 was filed with the patent office on 2009-04-23 for sheet transporting apparatus, and document reading apparatus and printing apparatus provided with the same.
Invention is credited to Hiromasa SHIBANO.
Application Number | 20090102118 12/210250 |
Document ID | / |
Family ID | 40562690 |
Filed Date | 2009-04-23 |
United States Patent
Application |
20090102118 |
Kind Code |
A1 |
SHIBANO; Hiromasa |
April 23, 2009 |
SHEET TRANSPORTING APPARATUS, AND DOCUMENT READING APPARATUS AND
PRINTING APPARATUS PROVIDED WITH THE SAME
Abstract
A sheet transporting apparatus including: sheet sensors arranged
in a sheet transporting path; an enclosure door; a door sensor that
detects the open/close state of the enclosure door; a control unit
that determines the opened state or closed state of the enclosure
door on the basis of the result of the detection by the door
sensor, and makes a determination whether or not a sheet stays at
the respective portions of the sheet sensors and whether or not the
staying sheet is removed; and a display unit that displays a
portion where the sheet stays, wherein the control unit controls
such that it repeatedly makes a determination regarding the stay
and the removal of the sheet when the sheet stays in the sheet
transporting path and the enclosure door is opened, and updates the
display on the basis of the result of the determination.
Inventors: |
SHIBANO; Hiromasa;
(Yamatokoriyama-shi, JP) |
Correspondence
Address: |
MARK D. SARALINO ( SHARP );RENNER, OTTO, BOISSELLE & SKLAR, LLP
1621 EUCLID AVENUE, 19TH FLOOR
CLEVELAND
OH
44115
US
|
Family ID: |
40562690 |
Appl. No.: |
12/210250 |
Filed: |
September 15, 2008 |
Current U.S.
Class: |
271/265.03 |
Current CPC
Class: |
B65H 2551/21 20130101;
G03G 2215/0078 20130101; G03G 15/70 20130101; B65H 2601/11
20130101; B65H 2511/51 20130101; B65H 2220/02 20130101; G03G
2215/00548 20130101; B65H 2511/417 20130101; B65H 2511/528
20130101; G03G 2221/1675 20130101; B65H 7/06 20130101; G03G 15/502
20130101; B65H 2511/417 20130101; B65H 2220/03 20130101; B65H
2511/51 20130101; B65H 2220/01 20130101; B65H 2551/21 20130101;
B65H 2220/02 20130101; B65H 2511/417 20130101; B65H 2220/01
20130101; B65H 2511/51 20130101; B65H 2220/01 20130101; B65H
2220/09 20130101; B65H 2511/528 20130101; B65H 2220/03
20130101 |
Class at
Publication: |
271/265.03 |
International
Class: |
B65H 7/06 20060101
B65H007/06 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 17, 2007 |
JP |
2007-270406 |
Claims
1. A sheet transporting apparatus comprising: sheet sensors
arranged at plural portions in a sheet transporting path, through
which a sheet is transported, for detecting a sheet at the
respective portions; an enclosure door that shields the sheet
transporting path from the outside with the closed state thereof,
and can be opened for removing a sheet when the sheet stays in the
sheet transporting path; a door sensor that detects the open/close
state of the enclosure door; a control unit that determines the
opened state or closed state of the enclosure door on the basis of
the result of the detection by the door sensor, and makes a
determination as to whether or not a sheet stays at the respective
portions and whether or not the staying sheet is removed; and a
display unit that displays a portion where the sheet stays, when it
is determined that the sheet stays in the sheet transporting path,
wherein the control unit controls such that it repeatedly makes a
determination regarding the stay and the removal of the sheet when
the sheet stays in the sheet transporting path and the enclosure
door is opened, and updates the display of the portion where the
sheet stays on the basis of the result of the determination.
2. The sheet transporting apparatus according to claim 1, further
comprising an opening mechanism that can open and close a part of
the sheet transporting path for removing the staying sheet, and an
opening portion sheet sensor that is arranged at a openable portion
where the sheet transporting path is opened by the opening
mechanism, and can detect the sheet when the openable portion is
closed, wherein the control unit controls such that it repeatedly
makes a determination regarding the stay and the removal of the
sheet at the openable portion on the basis of the result of the
detection by the opening portion sheet sensor when the openable
portion is closed, and updates the display of the portion where the
sheet stays on the basis of the result of the determination, while
the control unit controls such that it does not make a
determination regarding the stay and the removal of the sheet and
does not update the display when the openable portion is
opened.
3. The sheet transporting apparatus according to claim 2, wherein
the opening mechanism further includes an opening mechanism sensor
that detects whether the opening mechanism is in its opened state
or in its closed state, wherein the control unit determines whether
it makes a determination regarding the stay and the removal of the
sheet at the openable portion and whether it updates the display
based on the result of the determination on the basis of the result
of the detection by the opening mechanism sensor.
4. The sheet transporting apparatus according to claim 1, further
comprising an instruction section that allows a user to make an
instruction, wherein the control unit updates the display on the
display unit when the instruction is given.
5. The sheet transporting apparatus according to claim 4, wherein
the control unit accepts the instruction only when the display unit
displays the portion where a sheet stays.
6. The sheet transporting apparatus according to claim 1, wherein
the control unit allows the display unit to display in a different
manner a portion where a sheet stays and a portion where a sheet
has been removed, when a sheet stays at plural portions.
7. The sheet transporting apparatus according to claim 1, wherein
the control unit makes it possible to transport a sheet at the
timing when the enclosure door is closed.
8. A document reading apparatus provided with the sheet
transporting apparatus according to claim 1.
9. A printing apparatus provided with the sheet transporting
apparatus according to claim 1.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is related to Japanese Patent Application
No. 2007-270406 filed on Oct. 17, 2007, whose priority is claimed
and the disclosure of which is incorporated by reference in its
entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the invention
[0003] The present invention relates to a sheet transporting
apparatus that detects a stay of a sheet in a sheet transporting
path and removal of this sheet, and displays the portion where the
sheet stays on a display unit, and a document reading apparatus and
a printing apparatus provided with the same.
[0004] 2. Description of the Related Art
[0005] There have been known document reading apparatuses provided
with a document transporting apparatus for transporting a
sheet-type document to a reading unit. The document reading
apparatus provided with the document transporting apparatus is
widely received in a market since it can save processing time and
labor for reading plural documents at a time. There have been known
printing apparatuses that can transport plural printing sheets one
by one for printing. The printing apparatus described above has
widely been received by the market since a user does not need to
set a printing sheet one by one to a sheet feed section upon
printing a printed matter composed of plural pages or plural
printings.
[0006] When a document or one printing sheet (hereinafter referred
to as a sheet) transported in a sheet transporting path is jammed
in the apparatus (sheet transporting apparatus) having a function
of transporting a sheet as described above, the next sheet has to
be stopped in the transporting path. Therefore, sheets stay in
various positions in the sheet transporting path. When the jamming
occurs, the sheet transporting apparatus detects the occurrence of
the jamming, stops the transportation of the sheet, and informs a
user of the occurrence of the jamming with a display or an alarm
sound. The sheet transporting apparatus not only displays the
occurrence of the jamming but also displays the portion where the
sheet stays on the display unit (display of a jam map) on the basis
of the result of the detection of a sheet sensor arranged at each
portion in the sheet transporting path. This is for reporting the
user where to access for removing the sheet. The user recognizing
the occurrence of the jamming opens a door (enclosure door)
provided at an enclosure section of the sheet transporting
apparatus, and removes the sheet staying at each portion in the
sheet transporting path as referring to the displayed jam map. When
the user operates a predetermined reset switch or closes the
enclosure door after the sheets are removed, the sheet transporting
apparatus checks whether or not a sheet still remains in the sheet
transporting path in response to the aforesaid operation. When
there is no sheet left behind in the sheet transporting path, the
sheet transporting apparatus restarts the operation. However, any
one of the sheet sensors detects a sheet, the sheet transporting
apparatus updates the jam map in accordance with the result of the
detection so as to inform the user of the sheet left behind in the
sheet transporting path. When the reset switch is operated or the
enclosure door is closed after all the remaining sheets are
removed, the sheet transporting apparatus restarts the
operation.
[0007] Recently, a highly functional sheet transporting apparatus
provided with plural sheet feed sections or a reverse path for
reading a double-sided document or for performing a double-sided
printing is commercially available. As the function is enhanced,
the sheet transporting path tends to be long and complicated. With
this, the possibility of a user forgetting to take out a sheet
tends to be high. In view of this, a design that makes it difficult
for a user to forget to take out a sheet has been proposed. For
example, an apparatus has been proposed (e.g., see Patent Document
1: Japanese Unexamined Patent Application No. H10-297795) in which
a portion from which a user is likely to forget to take out a sheet
is reported to the user for preventing the user from forgetting to
take out the remaining sheet, and the position of the remaining
sheet is displayed in a display manner according to the number of
times in the past in which the user forges to take out the sheet at
each position where the sheet remains, in order to save the
complicated and repeated labor for the removing operation. For
example, lighting/flickering display is made according to the
number of times of the user forgetting to take out a sheet, the
display is made with a different color according to the number of
times of the user forgetting to take out a sheet, the display is
made with a different size according to the number of times of the
user forgetting to take out a sheet, or the display is made with a
different pattern according to the number of times of the user
forgetting to take out a sheet.
[0008] In the conventional sheet transporting apparatus, when a
reset switch is depressed, or when an enclosure door is closed
after a jamming process, new information is acquired from a sheet
sensor arranged in a sheet transporting path, whereby a display
content of a jam map is updated. In the apparatus described above,
the jam map is updated only after the reset switch is depressed, or
after the enclosure door is closed, even with a state in which a
user forgets to take out a sheet from the sheet transporting path.
Since the jam map is not repeatedly updated during the sheet
removing operation, it can be said that the display is unkind to an
inexperienced user.
SUMMARY OF THE INVENTION
[0009] The present invention is accomplished in view of the
above-mentioned circumstance, and aims to provide a sheet
transporting apparatus that can repeatedly detect a status of a
sheet transporting path and can report the detected status to a
user even during when a user performs a sheet removing
operation.
[0010] The present invention provides a sheet transporting
apparatus including: sheet sensors arranged at plural portions in a
sheet transporting path, through which a sheet is transported, for
detecting a sheet at the respective portions; an enclosure door
that shields the sheet transporting path from the outside with the
closed state thereof, and can be opened for removing a sheet when
the sheet stays in the sheet transporting path; a door sensor that
detects the open/close state of the enclosure door; a control unit
that determines the opened state or closed state of the enclosure
door on the basis of the result of the detection by the door
sensor, and makes a determination as to whether or not a sheet
stays at the respective portions and whether or not the staying
sheet is removed; and a display unit that displays a portion where
the sheet stays, when it is determined that the sheet stays in the
sheet transporting path, wherein the control unit controls such
that it repeatedly makes a determination regarding the stay and the
removal of the sheet when the sheet stays in the sheet transporting
path and the enclosure door is opened, and updates the display of
the portion where the sheet stays on the basis of the result of the
determination.
[0011] Further, the present invention provides a document reading
apparatus provided with the sheet transporting apparatus.
[0012] Moreover, the present invention provides a printing
apparatus provided with the sheet transporting apparatus.
[0013] In the sheet transporting apparatus, the control unit
repeatedly makes a determination as to a stay and removal of a
sheet when a sheet stays and the enclosure door is opened, and
controls so as to update a display of the portion where the sheet
stays on the basis of the result of the determination. Therefore,
the sheet transporting apparatus can repeatedly detect the status
of the sheet transporting path and can report the detected status
to a user even during when the user performs a sheet removing
operation.
[0014] In the present invention, the enclosure door means the
respective doors mounted to the enclosure section for removing the
sheet staying in the sheet transporting path. The door may be a
revolving door having a hinge, or a drawout type door. Any type of
the mechanism thereof may be employed if it is openable and
closable. Further, no special limitations are imposed on the
position and shape thereof.
[0015] The preferable embodiments of the present invention will be
described below.
[0016] The apparatus may further include an opening mechanism that
can open and close a part of the sheet transporting path for
removing the staying sheet, and an opening portion sheet sensor
that is arranged at a openable portion where the sheet transporting
path is opened by the opening mechanism, and can detect the sheet
when the openable portion is closed, the control unit may control
such that it repeatedly makes a determination regarding the stay
and the removal of the sheet at the openable portion on the basis
of the result of the detection by the opening portion sheet sensor
when the openable portion is closed, and updates the display of the
portion where the sheet stays on the basis of the result of the
determination, while the control unit may control such that it does
not make a determination regarding the stay and the removal of the
sheet and does not update the display when the openable portion is
opened. With this, as to the result of the detection by the opening
section sheet sensor, the control unit detects the status of the
sheet transporting path at this portion and can report the detected
status to a user, when the opening mechanism is closed.
[0017] The opening mechanism may further include an opening
mechanism sensor that detects whether the opening mechanism is in
its opened state or in its closed state, wherein the control unit
may determine whether it makes a determination regarding the stay
and the removal of the sheet at the openable portion and whether it
updates the display based on the result of the determination on the
basis of the result of the detection by the opening mechanism
sensor. With this, the control unit can detect that the opening
mechanism is closed on the basis of the result of the detection by
the opening mechanism sensor, and can detect the status of the
sheet transporting path with this detection.
[0018] The sheet transporting apparatus may further comprise an
instruction section that allows a user to make an instruction,
wherein the control unit may update the display on the display unit
when the instruction is given. By virtue of this, the display is
updated on receipt of the instruction from the user. Therefore, the
user can easily recognize the status change before and after the
instruction.
[0019] The control unit may accept the instruction only when the
display unit displays the portion where a sheet stays. By virtue of
this, the portion where the sheet stays is always displayed when
the user gives an instruction. Therefore, the user can surely
recognize the status change before and after the instruction.
[0020] The control unit may allow the display unit to display in a
different manner a portion where a sheet stays and a portion where
a sheet has been removed, when a sheet stays at plural portions. By
virtue of this, the user can easily recognize the portion where the
sheet is removed.
[0021] The control unit may make it possible to transport a sheet
at the timing when the enclosure door is closed.
[0022] Various preferable embodiments described above may be
combined.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is an explanatory view showing a display example of a
jam map according to an embodiment of the present invention;
[0024] FIG. 2 is an explanatory view showing an overall
configuration of the inside of a digital multifunction peripheral
according to the present embodiment;
[0025] FIG. 3 is an explanatory view showing the state in which a
transportation destination of a sheet is changed by plural branch
claws in the digital multifunction periphery according to the
present embodiment;
[0026] FIG. 4 is an explanatory view showing outer appearances of a
first unit, which can be drawn from a main body of a printing unit,
and a second unit in the digital multifunction periphery according
to the present embodiment;
[0027] FIG. 5 is an explanatory view showing the state in which the
first unit is drawn from the main body and the second unit is drawn
from the first unit in the digital multifunction periphery
according to the present embodiment;
[0028] FIG. 6 is a perspective view (corresponding to FIG. 4)
showing the state in which the first unit is drawn from the main
body in the digital multifunction periphery according to the
present embodiment;
[0029] FIG. 7 is a perspective view showing the state in which the
second unit 103 is drawn from the first unit in the digital
multifunction periphery according to the present embodiment;
[0030] FIG. 8 is an explanatory view showing the positions of sheet
sensors arranged along a sheet transporting path in the digital
multifunction periphery according to the present embodiment;
[0031] FIG. 9 is an explanatory view showing a modification of a
display screen of the jam map in FIG. 1;
[0032] FIG. 10 is an explanatory view showing a modification in
which the display screen of the jam map is different from that in
FIG. 1;
[0033] FIGS. 11A and 11B are first and second explanatory views
showing the detail of a procedure for removing a sheet staying in
the sheet transporting path in the digital multifunction periphery
according to the present embodiment;
[0034] FIGS. 12A and 12B are third and fourth explanatory views
showing the detail of a procedure for removing a sheet staying in
the sheet transporting path in the digital multifunction periphery
according to the present embodiment;
[0035] FIG. 13 is a fifth explanatory view showing the detail of a
procedure for removing a sheet staying in the sheet transporting
path in the digital multifunction periphery according to the
present embodiment; and
[0036] FIG. 14 is a sixth explanatory view showing the detail of a
procedure for removing a sheet staying in the sheet transporting
path in the digital multifunction periphery according to the
present embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] The present invention will be described in more detail below
with reference to the drawings. It should be understood that the
following description is illustrative of the invention in all
aspects, but not limitative of the invention.
<Configuration of Sheet Transporting Path>
[0038] Firstly, a configuration of a sheet transporting path of an
electrophotographic digital multifunction peripheral will be
explained as one example of a sheet transporting apparatus
according to the present invention. FIG. 2 is an explanatory view
showing an overall configuration of the inside of the digital
multifunction peripheral 11 according to the present embodiment.
The digital multifunction peripheral shown in FIG. 2 includes a
document reading unit 3 and a printing unit 1. The document reading
unit 3 has a document transporting apparatus 5. The printing unit 1
forms an image onto a printing sheet in accordance with a document
image read by the document reading unit 3 or print data received
from an external device through a communication line. This
corresponds to the aforesaid printing apparatus. Here, the sheet
transporting path of the printing unit 1 will be explained.
[0039] As shown in FIG. 2, the printing unit 1 has, around a
photosensitive drum 17 for forming an image by an
electrophotographic process, a charger 19, an exposure unit 13, a
developing device 15, a transfer mechanism (in the present
apparatus, a transfer belt unit having a transfer belt 45) 39, and
a cleaner unit 21. Further, the printing unit 1 includes a sheet
feed tray 25, a sheet-feed-side sheet transporting path 27, a
registration roller 29, a discharge-side sheet transporting path
31, a fixing unit 23, and a sheet exit tray 33. The transfer belt
unit 39 transfers the toner image, formed on the surface of the
photosensitive drum 17, onto a sheet.
[0040] The sheet feed tray 25 accumulates printing sheets. The
sheet feed tray 25 is arranged below an image forming unit, and at
the side wall face in the present apparatus. Plural sheet feed
trays 25 arranged below the image forming unit include trays 1 and
2, which are arranged side by side, at the uppermost stage. The
left one is the tray 1, while the right one is the tray 2. A tray 3
is arranged below the trays 1 and 2, and a tray 4 is arranged below
the tray 3. On the other hand, a large-capacity sheet feed tray 73
that can store 4000 sheets and a manual tray 75 used for printing
on a sheet of a non-standard size are arranged at the right side of
the apparatus.
[0041] The registration roller 29 temporarily stops the sheet
before the transfer belt unit 39 so as to be synchronous with the
toner image transferred onto the sheet. The sheet-feed-side
transporting path 27 extends upward from each of the sheet feed
trays 25 to reach the registration roller 29. The discharge-side
transporting path 31 is a path reaching a sheet exit roller 95
arranged at the outlet port to the sheet exit tray 33 through the
registration roller 29, the transfer belt 45 and the fixing unit
23. When the sheet passes the transfer belt 45, the toner image
formed onto the surface of the photosensitive drum 17 is
transferred onto the sheet as described above. The sheet-feed-side
transporting path 27 and the discharge-side transporting path 31
correspond to the sheet transporting path according to the present
invention. Although not shown in FIG. 2, a sheet sensor for
detecting a sheet is arranged in the sheet-feed-side transporting
path 27 and the discharge-side transporting path 31.
[0042] A branch claw 77 is arranged in the discharge-side
transporting path 31 over the fixing unit 23. By virtue of the
branch claw 77, the sheet can be guided to a transporting path 81
(see FIG. 3) branched from the discharge-side transporting path 31.
The transporting path 81 reaches a switchback unit 97 or the
registration roller 29 through the portion where branch claws 83,
85 and 89 (see FIG. 3) are arranged. A transporting path 87 that
guides the sheet to the sheet exit tray 33 from the switchback unit
97 is formed.
[0043] The image forming apparatus 11 has a control unit not shown.
The control unit controls the operation of the image forming
apparatus 11. The control unit is composed of, for example, a
microcomputer, a ROM, a RAM, a non-volatile memory, an input
circuit, an output circuit, and the like. The ROM stores a control
program that is a procedure executed by the microcomputer. The RAM
provides a work area to the microcomputer. The non-volatile memory
backs up data necessary for the control and retains the same. Input
signals from various sensors including the sheet sensor and
switches are inputted to the input circuit. The output circuit
includes a driver for driving various loads such as a drive motor
for transporting a sheet and a solenoid for driving the branch
claws.
[0044] FIG. 3 is an explanatory view showing the state in which the
transporting destination of the sheet is switched by plural branch
claws arranged in the vicinity of the inlet of the branched
transporting path described above. The detail of the changeover of
the discharge-side sheet transporting path 31 will be explained
below with reference to FIG. 3.
[0045] As shown in FIG. 3, the branch claw 77 makes a changeover as
to whether the sheet from the fixing unit 23 is transported to a
transporting path 79, which constitutes a part of the
discharge-side transporting path 31, or to the transporting path
81. Branch claws 83, 85, 89 and 92 are provided in the vicinity of
the outlet of the transporting path 81. The branch claws 77, 83, 85
and 89 are movable, and biased in one direction (first position) by
an elastic member. The branch claws 77, 85, and 89 can change their
positions (second position) against the biasing force through the
drive of the corresponding solenoids. The branch claw 92 is
stationary. The microcomputer drives the solenoids corresponding to
the branch claws 77, 85 and 89 so as to be capable of changing the
position of each branch claw to the second position. The branch
claw 85 can change its position to a third position by the
microcomputer and the drive solenoid.
[0046] The branch claw 83 is weakly biased toward the first
position by the elastic member. When the sheet abuts the branch
claw 83 in case where the later-described branch claw 85 is in the
second position, the branch claw 83 moves to the second position by
the stiffness at the leading end of the sheet and the transporting
force of a transport roller 93. However, the sheet conveyed from
the reverse direction, i.e., from a transporting path 84, cannot
enter the transporting path 81 because it is blocked by the branch
claw 83.
[0047] The branch claw 85 allows the sheet, which is conveyed from
the transporting path 81, to the transporting path 84 that reaches
the registration roller 29 in cooperation with the branch claw 83
at the first position. Further, it guides the sheet to a
transporting path 90 that reaches the switchback unit 97. It also
guides the sheet from the transporting path 84 to the transporting
path 87 that reaches the sheet exit tray 33.
[0048] The branch claw 89 guides, at the first position, the sheet
from the switchback unit 97 to the transporting path 87 that
reaches the sheet exit tray 33. Further, it guides, at the second
position, the sheet to the transporting path 84 that reaches the
registration roller 29.
[0049] The microcomputer controls the transportation of the sheet
as described below in accordance with the instructed printing
condition.
1) Face-Up Discharge in One-Sided Printing
[0050] The microcomputer moves the branch claw 77 to the first
position so as to guide the transported sheet to the transporting
path 79 at the timing when the sheet, which passes the fixing unit
23, passes through the transport roller 93 at the latest. The sheet
is discharged to the sheet exit tray 33 with a face-up state
through the sheet exit roller 95.
2) Face-Down Discharge in One-Sided Printing
[0051] The microcomputer moves the branch claw 77 to the second
position so as to guide the transported sheet to the transporting
path 81 at the timing when the sheet, which passes the fixing unit
23, passes through the transport roller 93 at the latest. Further,
the microcomputer moves the branch claw 85 to the first position.
The leading end of the transported sheet is guided by the branch
claw 77 to pass through the transporting path 81. The sheet further
passes through the outlet of the transporting path 81 against the
press-contact force by the branch claw 83 by the transporting force
of the transport roller 93 and the stiffness at the leading end of
the sheet, and reaches the branch claw 85. Thereafter, the leading
end of the sheet is guided by the branch claw 85 to be directed to
the transporting path 84. The microcomputer temporarily stops the
transportation of the sheet at the timing when the trailing end of
the sheet reaches the position of the branch claw 92. Then, the
microcomputer changes the position of the branch claw 85 to the
third position to open the transporting path 87 and to shield the
transporting path 90. The branch claw 83 is biased by the elastic
member to shield the transporting path 81 as described above. As
described above, after the position of the branch claw 85 is
changed, the microcomputer inversely rotates an inverse transport
roller 94 so as to transport the sheet in the direction reverse to
the entering direction. The sheet passes through the transporting
path 87 with the side thereof close to the branch claw 90, i.e.,
the trailing end of the sheet when it enters the transporting path
84, defined as the leading end, and is discharged to the sheet exit
tray 33 through the sheet exit roller 95.
3) Double-Sided Printing
[0052] The microcomputer moves the branch claw 77 to the second
position so as to open the transporting path 81 and shield the
transporting path 79 at the timing when an image is transferred
onto a first face (front surface) and the sheet passing through the
fixing unit 23 passes through the transport roller 93 at the
latest. Further, it moves the branch claw 85 to the second position
so as to open the transporting path 90 and shield the transporting
path 84. The microcomputer also changes the position of the branch
claw 89 so as to open the transporting paths 91 and 87 and shield
the transporting path 84. Further, the microcomputer changes the
position of the branch claw 89 so as to open the transporting paths
91 and 87 and shield the transporting path 84. The leading end of
the sheet is guided by the branch claw 77 to pass through the
transporting path 81. After the sheet passes through the branch
claw 83 by the stiffness of the leading end of the sheet and the
transporting force of the transport roller 93, the sheet is guided
by the branch claw 85 to pass through the transporting path 90 and
be directed to the transporting path 91. The microcomputer
temporarily stops the transportation of the sheet at the timing
when the trailing end of the sheet reaches the transporting path 91
(the switchback of the first face is completed). Then, the
microcomputer changes the branch claw 89 to the second position to
shield the transporting path 90 and open the transporting path 84.
Thereafter, the microcomputer inversely rotates a switchback roller
96, thereby transporting the sheet in the direction reverse to the
advancing direction to the switchback unit 97. The sheet passes
through the branch claws 89 and 92 and is directed to the
transporting path 84 with the trailing end of the sheet when it
enters the transporting path 91 defined as the leading end. Then,
the sheet is transported to the registration roller 29. Further,
the sheet is transported on the transfer belt 45 in synchronism
with the image on the second face. When the image on the second
face (back surface) is transferred onto the sheet and the sheet
passes through the fixing unit 23, the microcomputer moves the
branch claw 77 to the first position at the timing when the sheet
passes through the transport roller 93 at the latest. The
transported sheet is discharged to the sheet exit tray 33 through
the transporting path 79 and the sheet exit roller 95.
<Removal Method of Staying Sheet>
[0053] Explained next is the mechanism and procedure for removing a
sheet staying in the sheet transporting path by a user when a
jamming occurs at the printing unit 1 having the sheet transporting
path. The printing unit 1 has a mechanism of opening the sheet
transporting path so as to make it easy to remove the sheet by the
user when a jamming occurs. More specifically, the printing unit 1
is configured in a unit such that most part of the sheet
transporting path can be drawn in the near direction. The user can
draw the unit and access to the sheet transporting path after the
user opens a front door of an enclosure unit not shown. Instead of
the front door, a door may be provided to the side section.
[0054] FIG. 4 is an explanatory view showing outer appearances of a
first unit 101 and a second unit 103 that are units drawable from
the printing unit 1. Guide rails 98 and 99 are mounted to the main
body of the printing unit 1. The first unit 101 is mounted to the
main body through the guide rails 98 and 99. The second unit is
mounted to the first unit 101 through an unillustrated guide rail.
FIG. 4 shows the state in which the first unit 101 and the second
unit 103 are housed in the main body of the printing unit 1. The
sheet is transported in the sheet transporting path with this
state. For easy understanding, the first unit 101 and the second
unit 103 are indicated by a bold solid line.
[0055] A part of the sheet-feed-side transporting path 27 and the
discharge-side sheet transporting path 31 are positioned at the
upper part of the first unit 101. When the first unit 101 is drawn
from the main body, they are exposed. The user can easily remove
the sheet staying at the exposed portion with this state.
[0056] FIG. 5 is an explanatory view showing the state in which the
first unit 101 is drawn from the main body and the second unit 103
is drawn in the left direction from the first unit 101. With this
state, the transporting path 79 is exposed at the upper part at the
side of the sheet exit tray 33 of the second unit 103, the
transporting path 81 is exposed at the upper sheet-feed side, and
the transporting path 87 and the transporting path 90 are exposed
at the upper discharge side. Further, when the second unit 103 is
drawn from the first unit 101, the transporting path 84, the
transporting path from the inverse transport roller 94 to the
registration roller 29, the transporting path 91, and the
switchback unit 97 are exposed. The transporting path 84 is at the
upper part of the second unit 103, and the transporting path 91 and
the switchback unit 97 are at the lower part. As described above,
the user can easily remove the sheet staying in the transporting
paths 79, 81, 84, 87, 90 and 91, the transporting path from the
inverse transport roller 94 to the registration roller 29, and the
switchback unit 97 with the second unit 103 drawn from the first
unit 101.
[0057] FIG. 6 is the state corresponding to FIG. 4, and is a
perspective view showing the state in which the first unit 101 is
drawn from the main body. As shown in FIG. 6, a part of the
sheet-feed-side transporting path 27 and the sheet transporting
path 31 are exposed at the upper part of the first unit 101.
[0058] FIG. 7 is a perspective view showing the state in which the
second unit 103 is drawn from the first unit 101 from the state in
FIG. 6. FIG. 7 corresponds to FIG. 5. Although the detail of the
transporting paths is omitted in FIG. 7, the transporting path 84
and the transporting path from the inverse transport roller 94 to
the registration roller 29, which are hidden below the first unit
101, are exposed, and the transporting path 81, which is hidden
because it is sandwiched between the first unit 101 and the second
unit 103, is exposed, when the second unit 103 is drawn. The
transporting path 79 is exposed at the upper part of the second
unit 103, and the transporting paths 87 and 90 are exposed at the
side of the sheet exit tray 33 of the second unit 103. The
switchback unit 97 and the transporting path 91 are positioned at
the lower part of the second unit 103, but a user turns a
switchback roller 96 disposed in the transporting path 91 so as to
easily remove the sheet staying in the transporting path 91 and the
switchback unit.
<Arrangement of Sheet Sensor and Display of Jam Map>
[0059] An arrangement example of the sheet sensor according to the
present invention will be described. FIG. 8 is an explanatory view
showing the positions of sheet sensors arranged along the sheet
transporting path in the printing unit 1. The configuration of the
sheet transporting path corresponds to the printing unit 1 in FIG.
2. Among the sheet sensors shown in FIG. 8, sheet sensors SS01 to
07 are arranged at the main body of the printing unit. Sheet
sensors SS11 to 14 are arranged at the first unit 101. Sheet
sensors SS21 to 26 are arranged at the second unit 103. Each of the
sheet sensors is a reflective-type photointerrupter. Alternatively,
it may be a combination of a transmission photointerrupter and a
cantilever. It is well known that these are used for the detection
of a sheet.
[0060] When these sheet sensors detect jamming, the microcomputer
causes an operation panel section (not shown) of the digital
multifunction peripheral 11 to display a jam map. FIG. 1 is an
explanatory view showing an example of the display of the jam map
according to the present embodiment. The marks having a shape of
rotated triangle in FIG. 1 correspond to the sheet sensors, and
these marks are displays for indicating a position where a sheet
stays (jammed-position display). For example, a jammed-position J01
is displayed when the sheet sensor SS01 detects a stay of a sheet.
The jammed-position displays J02 to J07 correspond to the sheet
sensors S02 to 07 respectively. There are displays corresponding to
the sheet sensors SS11 to 14 and S21 to 26, but the numerals are
omitted, except for some ones, because the figure becomes
complicated.
[0061] Although the jammed-position displays corresponding to the
sheet sensors SS01 to 07, SS11 to 14 and SS21 to 26 are illustrated
in FIG. 1 for illustration, only the position where a sheet stays
is generally displayed. For example, when a sheet is fed from the
lowermost sheet feed tray, the displays of J02, J04, J05, J06 and
J07 corresponding to the sheet feed sections other than the
lowermost sheet feed tray are not displayed. When plural sheets
stay in the sheet transporting path, the jammed-position displays
corresponding to the portions where sheets stay are displayed. It
is well known that the position of the staying sheet in the sheet
transporting path is displayed onto the jam map according to the
result of the detection of each sheet sensor.
<Update of Jammed-Position Display During Removal Operation of
Sheet>
[0062] Next, a technique of updating the content of the
jammed-position display according to the status of the operation
for removing a sheet by a user will be explained. This is the
characteristic point of the present invention.
[0063] In the digital multifunction peripheral 11 according to the
present embodiment, a power source and signal wirings are
configured such that, even with the state in which a user opens an
enclosure door for removing a sheet staying in the sheet
transporting path of the printing unit 1, power supply is applied
to each sheet sensor so as to detect the presence or absence of the
sheet. The signal from each sheet sensor is directed to the input
circuit, whereby the microcomputer serving as a control unit can
read the result of the detection by each sheet sensor. The wirings
are configured such that power supply is fed to the main body of
the printing unit and the sheet sensors SS11 to 14 and SS21 to 26
arranged at the first and the second units with the first unit 101
drawn by a user, and the microcomputer can read the result of the
detection of each sheet sensor. For example, a bent beam is bridged
between a frame section at the far side (not shown) of the main
body of the printing unit and the frame at the far side of the
first unit 101, wherein the power source and signal wiring of each
sheet sensor are hung down to form a wiring arch. The wirings are
configured such that power supply is fed to the sheet sensors SS21
to 26 arranged at the second unit with the second unit 103 drawn
from the first unit 101 by a user, and the microcomputer can read
the result of the detection of each sheet sensor. For example, a
bent beam is bridged between the first unit and the second unit,
wherein the power source and signal wiring of each sheet sensor are
hung down to form a wiring arch. The beam is preferably mounted at
the position indicated by a chain line of 105 in FIG. 5.
[0064] In order to remove the staying sheet, the digital
multifunction peripheral 11 is provided with the portion where an
opening mechanism for opening the transporting path in the vicinity
of the portion where the sheet stays and a portion where a knob or
the like is provided for manually transporting the sheet in the
vicinity of the portion where the sheet stays, as described later,
wherein a user turns the knob for moving the staying sheet.
[0065] As for the portion where the user turns the knob to move the
sheet to the open end of the sheet transporting path in order to
remove the sheet, the microcomputer always reads the signal from
the sheet sensor arranged at this portion. The microcomputer
continues to monitor the status as to whether the sheet stays or is
removed, and updates the display of the jam map. In this case, in
order to prevent the erroneous detection of noise superimposed on
the signal from the sensor, it is preferable that the microcomputer
samples the output from the sensor at an interval of about 50 to
100 ms, and when the results of the sampling agree with each other
five times to ten times in succession, this state is adopted as the
result of the detection. By virtue of this, the noise from the
electrical noise having relatively short cycle such as a jitter to
the noise having relatively long cycle such as a mechanical bounce
from an actuator can be eliminated, whereby a stable detection can
be carried out.
[0066] On the other hand, as for the portion where the opening
mechanism is provided, and the staying sheet is removed after the
sheet transporting path in the vicinity of the portion where the
sheet stays is opened by the user, it is difficult to correctly
detect the sheet by the sheet sensor with the sheet transporting
path opened, because of its mechanical structure. In view of this,
the microcomputer stops the reading of the signal from the sheet
sensor when the sheet transporting path is opened. When the sheet
transporting path is closed, the microcomputer samples the signal
from the sheet sensor. Therefore, a sensor for detecting the
open/close state is provided to the opening mechanism. It is
preferable that the signal is sampled at an interval of about 50 to
100 ms, and when the results of the sampling agree with each other
five times to ten times in succession, this state is adopted as the
result of the detection from the viewpoint of achieving the stable
detection.
[0067] By virtue of this, the display of the jam map is not updated
with the sheet transporting path at the portion where the user
removes the sheet opened. However, when the sheet transporting path
at this portion is closed, the display of the jam map is updated.
Therefore, compared to the case in which the jam map is updated
only after the sheet at the other portions is removed and the front
door is closed, the display of the jam map is updated, which is
effective for preventing the user from forgetting to take out the
sheet. That is, when another sheet stays at the portion where the
sheet removing operation is carried out, the display of the jam map
remains at the time when the sheet transporting path at this
portion is closed, so that the user confirming the display
recognizes that he/she forgets to take out the sheet.
[0068] For example, it is supposed that a sheet that a user forgets
to take out is present at the second unit 103. In the conventional
case, it is after the second unit 103 is inserted in the first unit
101, the first unit 101 is inserted in the main body of the
printing unit, and the front door is closed when the user
recognizes that he/she forgets to take out the sheet. It is
because, since the display of the jam map is not updated until the
front door is closed, the condition of the staying sheet is not
correctly displayed. In this case, the user should open the front
door again, draw the first unit 101, draw the second unit 103 to
remove the sheet, which is left behind, then insert the second unit
103, insert the first unit 101, close the front door, and confirm
whether the redoing operation is well done or not. On the other
hand, according to the present embodiment, after the sheet is
correctly removed, the jammed-position display of the corresponding
portion is turned off at the time when the sheet transporting path
is closed. The user confirms the jammed-position displays after
carrying out the removing operation at each jammed position, and
can recognize that there is no sheet left behind. Accordingly, even
if there is a sheet that is left behind, the user can easily remove
the sheet again. The present invention can remarkably enhance the
convenience of a user involved with the sheet removing
operation.
[0069] FIG. 9 is an explanatory view showing a modification of the
screen of the display of the jam map in FIG. 1. The modification is
different from the display screen of the jam map in FIG. 1 in that
an "update" button B1 is added. In FIG. 9, it is the presumption
that the display section has a touch panel. Therefore, when the
user touches the "update" button, the microcomputer can read this
state. In the modification, the microcomputer continuously monitors
the status of each sheet sensor like the embodiment described
above. However, different from the embodiment described above, it
does not continuously update the display screen of the jam map.
Instead of this, the display of the jam map is updated when the
"update" button B1 is depressed. With this structure, the user can
recognize the status change only when he/she updates the display of
the jam map according to his/her wish. There is a viewpoint that
the user more easily recognizes the status change in the
modification than in the aforesaid embodiment in which the display
of the jam map is updated during the sheet removing operation.
However, the modification is poor in real time performance, since
the display of the jam map is not updated until the user depresses
the update button.
[0070] The microcomputer displays the "update" button B1 only on
the display screen of the jam map. Therefore, when the user
depresses the "update" button B1, the user can surely recognize the
change between the status of the staying sheet before the update
and the status of the staying sheet after the update.
[0071] FIG. 10 is an explanatory view showing a modification in
which the display screen of the jam map is different from that in
FIG. 1. In the example in FIG. 10, the portion where a sheet stays
is indicated by mark when jamming occurs. After the sheet is
removed, the jammed-position display is not turned off but the mark
indicating the jammed-position display is changed to mark. In FIG.
10, the jammed-position displays J12, J13 and J26 are indicated by
mark. This shows that a sheet staying at the portion where the
sheet sensors SS12, SS13 and SS26 are arranged is removed. On the
other hand, the jammed-position displays J01, J03, or the like are
indicated by mark. This shows that a sheet still stays at the
portion corresponding to these jammed positions. By virtue of this,
the user can exactly grasp the portion where the sheet has already
been removed. The display manner for the removed sheet is not
limited to the mark. The display manner can be changed, for
example, such that the other mark such as .quadrature. mark is
employed, the status is distinguished by a lighting display and
flickering display, a color is made different, or the size of the
jammed-position display is made different.
<Detail of Removal Procedure of Staying Sheet>
[0072] FIGS. 11 to 14 are explanatory views for showing the detail
of the procedure for removing a staying sheet in the sheet
transporting path of the printing unit 1. FIGS. 11 to 13 show the
procedure for removing a sheet staying in the first unit 101 and
the second unit 103. FIG. 14 shows the procedure for removing a
sheet staying in the longitudinal transporting path of the
sheet-feed-side transporting path 27.
[0073] Before a procedure 3 in FIG. 11A, there are a procedure 1
for releasing the lock of the front door of the enclosure section
and a procedure 2 for opening the front door, but these procedures
are not illustrated. In the procedure 3, a drawing lever is turned
to bring the first unit 101 in the drawable state, and in the
procedure 4, the first unit 101 (including the second unit 103) is
drawn in the near direction and locked. In a procedure 5, if there
is a sheet detected by the sheet sensor SS07, the user removes this
sheet. The microcomputer continuously reads the sheet sensor SS07.
After the sheet is removed, the microcomputer turns off the
jammed-position display J07 corresponding to the removed sheet.
[0074] When there is a sheet that is conveyed from the sheet feed
tray 25 and detected by the sheet sensor SS11 in the procedures 6
and 7 in FIG. 11B, the user turns the knob to remove this sheet.
The microcomputer continuously reads the sheet sensor SS11. After
the sheet is removed, the microcomputer turns off the
jammed-position display J11 corresponding to the removed sheet.
When there is a sheet that is conveyed from the manual tray 75 and
detected by the sheet sensor SS11 in the procedures 8 and 9, the
user lays down a paper guide to open the sheet transporting path,
and removes the sheet. The collapsible paper guide corresponds to
the opening mechanism. The microcomputer discontinues the reading
of the sheet sensor SS11 during when the paper guide is opened, and
restarts the reading after the paper guide is closed. If the sheet
is removed when the paper guide is closed, the microcomputer turns
off the jammed-position display J11.
[0075] When there is a sheet detected by the sheet sensor SS12 in
procedures 10 and 11 in FIG. 12A, the user lays down the paper
guide to open the sheet transporting path, and removes the sheet.
The collapsible paper guide corresponds to the opening mechanism.
The microcomputer discontinues the reading of the sheet sensor SS12
during when the paper guide is opened, and restarts the reading
after the paper guide is closed. If the sheet is removed when the
paper guide is closed, the microcomputer turns off the
jammed-position display (the mark is not shown in FIG. 1).
[0076] Next, the user draws the second unit 103 in the procedure
12. When there is a sheet detected by the sheet sensor SS14 in
procedure 13 and procedure 14 in FIG. 12B, the user turns the knob
to remove this sheet. The microcomputer continuously reads the
sheet sensor SS11. When the sheet is removed, the microcomputer
turns off the jammed-position display (the mark is not shown in
FIG. 1) corresponding to the sheet sensor SS11.
[0077] When there is a sheet detected by the sheet sensor SS26 in
procedures 15 and 16, the user lifts up the paper guide to open the
sheet transporting path at this portion, and removes the sheet. The
movable paper guide corresponds to the opening mechanism. The
microcomputer discontinues the reading of the sheet sensor SS26
during when the paper guide is opened, and restarts the reading
after the paper guide is closed. If the sheet is removed when the
paper guide is closed, the microcomputer turns off the
jammed-position display J26 corresponding to the sheet sensor
SS26.
[0078] When there is a sheet detected by the sheet sensor SS25 in
procedures 17 and 18, the user opens the paper guide to open the
sheet transporting path at this portion, and removes the sheet. The
movable paper guide corresponds to the opening mechanism. The
microcomputer discontinues the reading of the sheet sensor SS25
during when the paper guide is opened, and restarts the reading
after the paper guide is closed. If the sheet is removed when the
paper guide is closed, the microcomputer turns off the
jammed-position display (the mark is not shown in FIG. 1)
corresponding to the sheet sensor SS25.
[0079] When there is a sheet detected by the sheet sensor SS23
and/or the sheet sensor SS23 in procedures 19 and 20 in FIG. 13,
the user lifts up the paper guide to open the sheet transporting
path at this portion, and removes the sheet. The movable paper
guide corresponds to the opening mechanism. The microcomputer
discontinues the reading of the sheet sensors SS22 and SS23 during
when the paper guide is opened, and restarts the reading after the
paper guide is closed. If the sheet is removed when the paper guide
is closed, the microcomputer turns off the jammed-position displays
(the numerals are not shown in FIG. 1) corresponding to the sheet
sensors SS22 and SS23.
[0080] When there is a sheet detected by the sheet sensor SS24 in
procedures 21 and 22, the user lifts up the paper guide to open the
sheet transporting path at this portion, and removes the sheet. The
movable paper guide corresponds to the opening mechanism. The
microcomputer discontinues the reading of the sheet sensor SS24
during when the paper guide is opened, and restarts the reading
after the paper guide is closed. If the sheet is removed when the
paper guide is closed, the microcomputer turns off the
jammed-position display (the numeral is not shown in FIG. 1)
corresponding to the sheet sensors SS24.
[0081] Subsequently, FIG. 14 will be explained. FIG. 14 is a
procedure for removing the sheet staying in the longitudinal
transporting path of the sheet-feed-side transporting path 27. The
user opens the front door of the enclosure section in a procedure 1
in FIG. 14. When there is a sheet detected by the sheet sensor SS11
in a procedure 2, the user removes this sheet. The procedure for
removing the sheet detected by the SS11 has already been explained
in the procedures 6 and 7 in FIG. 11. When the drawing of the first
unit 101 is preceding as the sheet removing operation, the sheet is
removed in the procedures 6 and 7 in FIG. 11. When the confirmation
of the longitudinal transporting path of the sheet-feed-side
transporting path 27 is preceding, the sheet is removed in this
procedure. After the sheet is removed, the microcomputer turns off
the jammed-position display J11 corresponding to the sheet sensor
SS11.
[0082] When there is a sheet detected by the sheet sensor SS03 in
procedures 3 and 4, the user opens the paper guide to open the
transporting path at this portion, and removes the sheet. The
movable paper guide corresponds to the opening mechanism. The
microcomputer discontinues the reading of the sheet sensor SS03
during when the paper guide is opened, and restarts the reading
after the paper guide is closed. If the sheet is removed when the
paper guide is closed, the microcomputer turns off the
jammed-position display J03 corresponding to the sheet sensor
SS03.
[0083] In the present embodiment, the case in which the jam map is
displayed is taken as an example. However, instead of the jam map,
a configuration in which a name or number for identifying each
sheet sensor is displayed, or the configuration in which these are
displayed as a message, can be employed, as a modification.
[0084] Various modifications are possible for the present invention
in addition to the embodiment described above. It should be
understood that such modifications also fall within the aspects and
scope of the present invention. The present invention is intended
to embrace all alterations made within the scope of the invention
defined by the appended claims and their equivalents.
* * * * *