U.S. patent application number 11/514958 was filed with the patent office on 2007-03-22 for paper sheet conveying apparatus.
This patent application is currently assigned to KABUSHIKI KAISHA TOSHIBA. Invention is credited to Akihiro Yui.
Application Number | 20070063426 11/514958 |
Document ID | / |
Family ID | 37496597 |
Filed Date | 2007-03-22 |
United States Patent
Application |
20070063426 |
Kind Code |
A1 |
Yui; Akihiro |
March 22, 2007 |
Paper sheet conveying apparatus
Abstract
A paper sheet conveying apparatus has a conveying belt which
moves and conveys a paper sheet, a detection sensor which detects
the amount of displacement of the conveying belt from a reference
position while moving, and a control device which drives the
conveying belt at a low speed when a new device is installed as a
conveying belt and initially started up, and after the low-speed
driving, variably controls the speed of the conveying belt based on
the amount of displacement of the conveying belt detected by the
detection sensor.
Inventors: |
Yui; Akihiro; (Yokosuka-shi,
JP) |
Correspondence
Address: |
PILLSBURY WINTHROP SHAW PITTMAN, LLP
P.O. BOX 10500
MCLEAN
VA
22102
US
|
Assignee: |
KABUSHIKI KAISHA TOSHIBA
Tokyo
JP
|
Family ID: |
37496597 |
Appl. No.: |
11/514958 |
Filed: |
September 5, 2006 |
Current U.S.
Class: |
271/204 |
Current CPC
Class: |
B65H 2513/52 20130101;
B65H 2220/01 20130101; B65H 2220/11 20130101; B65H 2220/11
20130101; B65H 2220/02 20130101; B65H 2220/03 20130101; B65H
2513/10 20130101; B65H 2557/61 20130101; B65H 2701/1912 20130101;
B65H 2513/10 20130101; B65H 5/021 20130101; B65H 2513/40 20130101;
B65H 2513/52 20130101; B65H 2513/40 20130101 |
Class at
Publication: |
271/204 |
International
Class: |
B65H 29/04 20060101
B65H029/04 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 16, 2005 |
JP |
2005-269985 |
Claims
1. A paper sheet conveying apparatus comprising: a conveying belt
which moves and conveys a paper sheet; a detection device which
detects the amount of displacement of the conveying belt from a
reference position while moving; and a control device which drives
the conveying belt at a low speed when a new device is installed as
a conveying belt and initially started up, and after the low-speed
driving, variably controls the speed of the conveying belt based on
the amount of displacement of the conveying belt detected by the
detection device.
2. The paper sheet conveying apparatus according to claim 1,
wherein the control device leaves the conveying belt driven at a
low speed when the amount of displacement of the conveying belt is
over a predetermined value, gradually increases the speed of the
conveying belt as the amount of displacement of the conveying belt
is decreased, and increases the speed of the conveying belt to a
predetermined speed when the amount of displacement of the
conveying belt falls within given limits.
3. The paper sheet conveying apparatus according to claim 2,
further comprising a first notify device which notifies an
estimated time that the amount of displacement of the conveying
belt falls within given limits.
4. The paper sheet conveying apparatus according to claim 3,
further comprising a second notify device which notifies states
that the amount of displacement of the conveying belt is over a
predetermined value, decreased, and falls within given limits,
respectively.
5. A paper sheet conveying apparatus comprising: a conveying belt
which moves and conveys a paper sheet; a detection device which
detects the amount of displacement of the conveying belt from a
reference position while moving; a temperature detection device
which detects an ambient operating temperature of the conveying
belt; and a control device which drives the conveying belt at a low
speed when the temperature of the conveying belt at startup of
driving detected by the temperature detection device is lower than
a reference temperature, and after the low-speed driving, controls
the speed of the conveying belt based on the amount of displacement
of the conveying belt detected by the detection device.
6. The paper sheet conveying apparatus according to claim 5,
wherein the control device controls to gradually increase the
moving speed of the conveying belt as the temperature detected by
the temperature detection device is increased, and to increase the
moving speed of the conveying belt to a predetermined speed when
the temperature detected by the temperature detection device
becomes a predetermined value.
7. A paper sheet conveying apparatus comprising: a conveying belt
which moves and conveys a paper sheet; a detection device which
detects the amount of displacement of the conveying belt from a
reference position while moving; a judgment device which judges
whether the conveying belt has been stopped for over a certain
period, at startup of driving the conveying belt; and a control
device which drives the conveying belt at a low speed when the
judgment device judges the conveying belt to have been stopped for
over a certain period, and after the low-speed driving, controls
the speed of the conveying belt based on the amount of displacement
of the conveying belt detected by the detection device.
8. The paper sheet conveying apparatus according to claim 7,
further comprising a measuring device which measures a cumulative
driven time of the conveying belt, and time passed after the
installation of the conveying belt, wherein the judgment device
judges whether the conveying belt has been stopped for over a
certain time, based on the value measured by the measuring
device.
9. The paper sheet conveying apparatus according to claim 8,
further comprising a third notify device which notifies replacement
of the conveying belt, based on the amount of displacement of the
paper sheet detected by the detection device, the cumulative driven
time of the conveying belt measured by the measuring device, and
the time passed after the installation of the conveying belt.
10. A paper sheet conveying apparatus comprising: a conveying belt
which moves and conveys a paper sheet; a jam detection device which
detects a jam of a paper sheet conveyed by the conveying belt; a
detection device which detects the amount of displacement of the
conveying belt from a reference position after the paper jam is
cleared; a judgment device which judges whether the conveying belt
is to be driven, based on the amount of displacement of a paper
sheet detected by the detection device; and a control device which
drives the conveying belt at a low speed, when the judgment device
judges the conveying belt to be driven, and after the low-speed
driving, variably controls the speed of the conveying belt based on
the amount of displacement detected by the detection device.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of
priority from prior Japanese Patent Application No. 2005-269985,
filed Sep. 16, 2005, the entire contents of which are incorporated
herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a paper sheet conveying
apparatus used in a paper money processing machine, for
example.
[0004] 2. Description of the Related Art
[0005] A paper money processing machine sets paper money in a
take-out unit, takes out and conveys the set paper money one by one
through a conveying belt, judges the kind, front/back, true/false,
and normal/damaged of the conveyed paper money by a judgment
device, classifies the paper money according to the results of
judgment, and stacks the paper money in a plurality of stacking
box.
[0006] A paper money processing machine, particularly, a
large-scale machine processing at middle and high speeds uses a
conveying motor to drive a conveying belt at middle and high
speeds. A belt with a relatively low expansion rate (difficult to
expand) is used as a conveying belt, and stretched over with a
strong tension, in order to withstand such driving at middle and
high speeds.
[0007] However, a conveying belt is stretched over with such a
strong tension, the belt will be accustomed to being tightly
stretched when assembling the machine or replacing the belt, or
after installing a new conveying belt.
[0008] If a machine operation speed is increased to a normal
operation speed immediately after power is turned on, the conveying
belt may move zigzag, come off, or break.
[0009] Therefore, in a conventional machine, a release motor is
provided in addition to a conveying motor. When assembling the
machine or replacing the belt, the operator opens the machine door,
and uses the release motor to move the conveying belt at a low
speed as a test run. By this test run, the belt is familiarized to
the surrounding conditions, and prevented from getting habits.
(Refer to Jpn. Pat. Appln. KOKAI Publication No. 2003-276904, for
example.)
[0010] However, in the past, judgment on whether a conveying belt
is familiarized depends on the sense and experience of a machine
assembling or maintenance engineer. The judgment is not always
correct. If misjudgment occurs, a conveying belt is driven before
being familiarized with the conveying rollers, causing meandering,
coming off, or breaking. This is a problem, particularly in a
middle/high speed paper money processing machine.
[0011] Further, the work to familiarize a conveying belt is
dangerous, because a conveying mechanism is operated by opening the
machine door.
[0012] A conveying belt may also be accustomed to being expanded,
when an ambient operating temperature is low, or when the belt has
not been used for a certain period, as well as immediately after
assembling the machine, or replacing the belt. In such a case, a
test run is often not performed at startup of operation, and the
belt shifts or comes out, causing a paper jam.
[0013] When a paper jam occurs, a jammed paper sheet is removed and
the conveying belt is re-driven, but in this case, sometimes the
belt may be going to come off. If the conveying belt is re-driven
in such a condition, a secondary jam may occur causing a serious,
trouble such as, breaking of the belt.
[0014] Further, to remove a jammed paper sheet, the operator opens
the machine door and moves the conveying belt by using the release
motor. This is very dangerous.
[0015] Some types of machine turn off power when the door is
opened, and permit the operator to remove a jammed paper sheet by
operating a conveying system by a hand knob. However, when the
conveying system is long and includes a plurality of module, there
arises a problem that the operator does not easily clear a paper
jam.
BRIEF SUMMARY OF THE INVENTION
[0016] The present invention has been made under the above
circumstances. Accordingly, it is an object of the invention to
provide a paper sheet conveying apparatus, which is configured to
make automatic, safe and quantitative adjustment to familiarize a
conveying belt.
[0017] According to a first aspect of the invention, there is
provided a paper sheet conveying apparatus comprising a conveying
belt which moves and conveys a paper sheet; a detection device
which detects the amount of displacement of the conveying belt from
a reference position while moving; and a control device which
drives the conveying belt at a low speed when a new device is
installed as a conveying belt and initially started up, and after
the low-speed driving, variably controls the speed of the conveying
belt based on the amount of displacement detected by the detection
device.
[0018] According to a second aspect of the invention, there is
provided a paper sheet conveying apparatus comprising a conveying
belt which moves and conveys a paper sheet; a detection device
which detects the amount of displacement of the conveying belt from
a reference position while moving; a temperature detection device
which detects an ambient operating temperature of the conveying
belt; and a control device which drives the conveying belt at a low
speed when the temperature of the conveying belt at startup of
driving detected by the temperature detection device is lower than
a reference temperature, and after the low-speed driving, controls
the speed of the conveying belt based on the amount of displacement
of the conveying belt detected by the detection device.
[0019] According to a third aspect of the invention, there is
provided a paper sheet conveying apparatus comprising a conveying
belt which moves and conveys a paper sheet; a detection device
which detects the amount of displacement of the conveying belt from
a reference position while moving; a judgment device which judges
whether the conveying belt has been stopped for over a certain
period at startup of driving the conveying belt;.and a control
device which drives the conveying belt at a low speed when the
judgment device judges the conveying belt to have been stopped for
over a certain period, and after the low-speed driving, controls
the speed of the conveying belt based on the amount of displacement
of the conveying belt detected by the detection device.
[0020] According to a fourth aspect of the invention, there is
provided a paper sheet conveying apparatus comprising a conveying
belt which moves and conveys a paper sheet; a jam detection device
which detects a jam of a paper sheet conveyed by the conveying
belt; a detection device which detects the amount of displacement
of the conveying belt from a reference position after the paper jam
is cleared; a judgment device which judges whether the conveying
belt is to be driven based on the amount of displacement of a paper
sheet detected by the detection device; and a control device which
drives the conveying belt at a low speed when the judgment device
judges the conveying belt to be driven, and after the low-speed
driving, variably controls the speed of the conveying belt based on
the amount of displacement detected by the detection. device.
[0021] According to a further aspect of the invention, it is
possible to make automatic and quantitative adjustment to
familiarize a conveying device, at startup of the first drive after
a new conveying device is installed, thereby preventing a conveying
device from meandering, coming out, and breaking.
[0022] Besides, after a paper jam is cleared, it is possible to
determine whether a conveying device is to be driven, thereby
preventing a secondary paper jam.
[0023] Moreover, it is possible to notify a replacement period
before a conveying device reaches the end of life, thereby
preventing a paper jam.
[0024] Additional objects and advantages of the invention will be
set forth in the description which follows, and in part will be
obvious from the description, or may be learned by practice of the
invention. The objects and advantages of the invention may be
realized and obtained by means of the instrumentalities and
combinations particularly pointed out hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0025] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate embodiments of
the invention, and together with the general description given
above and the detailed description of the embodiments given below,
serve to explain the principles of the invention.
[0026] FIG. 1 is an external perspective view of a paper sheet
processing apparatus according to a first embodiment of the
invention;
[0027] FIG. 2 is a plane view showing a conveying belt in the paper
sheet processing apparatus of FIG. 1;
[0028] FIG. 3 is a front view showing the conveying belt of FIG.
2;
[0029] FIGS. 4A to 4C are graphs, each showing the amount of
displacement of the conveying belt of FIG. 2;
[0030] FIGS. 5A to 5C are graphs, each showing the amount of
displacement of the conveying belt of FIG. 2;
[0031] FIG. 6 is a block diagram showing a drive control system of
the conveying belt of FIG. 2;
[0032] FIGS. 7A to 7C are graphs, each showing the amount of
displacement of the conveying belt of FIG. 6;
[0033] FIGS. 8A to 8C are graphs, each showing a rotation speed of
a conveying motor of the conveying belt of FIG. 6;
[0034] FIGS. 9A to 9C are graphs, each showing changes in an
ambient operating temperature detected by a temperature sensor of
FIG. 6;
[0035] FIGS. 10A to 10C are graphs, each showing a rotation speed
of a conveying motor variable based on the changes in the ambient
operating temperatures of FIG. 9;
[0036] FIG. 11 is a block diagram showing a drive control system of
a conveying belt according to a second embodiment of the
invention;
[0037] FIGS. 12A to 12C are graphs, each showing drive states of
the conveying belt of FIG. 11;
[0038] FIGS. 13A to 13C are graphs, each showing the amount of
displacement of the conveying belt of FIG. 11;
[0039] FIG. 14 is a block diagram showing a drive control system of
a conveying belt according to a third embodiment of the
invention;
[0040] FIG. 15 is a plane view showing a state that the conveying
belt of FIG. 14 comes out;
[0041] FIGS. 16A to 16C are graphs, each showing changes in a
rotation speed of a conveying motor of FIG. 14; and
[0042] FIGS. 17A to 17C are graphs, each showing the amount of
displacement of the conveying belt of FIG. 14.
DETAILED DESCRIPTION OF THE INVENTION
[0043] Hereinafter, preferred embodiments of the invention will be
explained in detail with reference of the accompanying
drawings.
[0044] FIG. 1 is a schematic diagram showing a paper sheet
processing apparatus according to an embodiment of the
invention.
[0045] The paper sheet processing apparatus has a main body 100.
The front side of the main body 100 can be opened and closed by a
door 100a. A take-out unit 1 is provided on one side within the
main body 100. The take-out unit 1 is provided with a take-out
rotor 8 to take out a stack of paper sheet P one by one
sequentially from the top. The paper sheet P taken out by the
take-out rotor 8 is held and conveyed by a conveying device at a
constant speed. The conveying device 2 is provided with a processor
3, which performs various processing for the paper sheet P. The
take-out side of the processor 3 is branched into first and second
conveying paths 9 and 11. At the branching point, a first sorting
gate 4 is provided to sort the paper sheet P to the first and
second conveying paths 9 and 11. The take-out side of the first
conveying path 9 is branched into third and fourth 13 and 14. At
the branching point, a second sorting gate 12 is provided. The
third and fourth conveying paths 13 and 14 are connected to first
and second stacking units 5a and 5b, and the second conveying path
11 is connected to a stacking unit 6 for ejection.
[0046] In the first conveying path 9, an optical sensor 15 is
provided to count the number of passing paper sheets. Each time the
optical sensor 15 detects 100 sheets, the second sorting gate 12 is
operated to sort the paper sheets to the direction of the first or
second stacking unit 5a or 5b.
[0047] In the above configuration, the paper sheet P taken out from
the take-out unit 1 is conveyed to the processor 3 by the conveying
device 2, and processed there. Based on the processed information,
the first sorting gate 4 is operated to sort the paper sheet P to
the first or second conveying path 9 or 11. The paper sheet sorted
to the second conveying path 11 is stacked in the stacking unit 6
for ejection. The paper sheet P sorted to the second conveying path
9 is set to the first stacking unit 5a through the third conveying
path 13, and stacked there. When 100 sheets are stacked in the
first stacking unit 5a, the second sorting gate is operated to send
the paper sheet P to the second stacking unit 5b through the fourth
conveying path 14, and stacked there. The paper sheets P stacked in
the first and second stacking units 5a and 5b are stacked again as
a bundle. Likewise, the paper sheet stacked in the stacking unit 6
for ejection is stacked as a bundle.
[0048] FIG. 2 is a plane view showing the above-mentioned conveying
device 2. FIG. 3 is a front view of the conveying device.
[0049] The conveying device 2 has a pair of conveying belts 21a and
21b provided parallel with a predetermined space. The conveying
belts 21a and 21b are extended over conveying rollers 22. The
conveying roller 22 is rotatably fixed to a support shaft 23. The
support shaft 23 is fixed to a unit frame 24. The conveying roller
22 is driven by a conveying motor 25. The conveying belts 21a and
21b are moved by the rotation of the motor.
[0050] In the vicinity of the conveying belts 21a and 21b, a
detection sensor 27 is provided as a detection device to detect the
amount of displacement of the belts while moving. The detection
sensor 27 detects the amount of displacement of the conveying belts
21a and 21b while moving, as shown in FIG. 4 and FIG. 5.
[0051] FIG. 4A shows the state that the amount of displacement of
one conveying belt 21a is large. FIG. 4B shows the state that the
amount of displacement of the conveying belt 21a is improved. FIG.
4C shows the state that the amount of displacement of the conveying
belt 21a falls within given limits and the belt is stabilized.
[0052] FIG. 5A shows the state that the amount of displacement of
the other conveying belt 21b is large. FIG. 5B shows the state that
the amount of displacement of the conveying belt 21b is improved.
FIG. 5C shows the state that the amount of displacement of the
conveying belt 21b falls within given limits and the belt is
stabilized.
[0053] FIG. 6 shows the drive control system of the conveying
system configured as described above.
[0054] The detection sensor 27 is connected to a control device 29,
as a control device/a judgment device, through a transmission
circuit. The control device 29 is connected to the conveying motor
25 of the conveying belt 21a/21b, and is connected to first and
second notify units as first and second notify devices, through the
control circuit. The control device 29 is also connected to a
temperature sensor 28 as a temperature detection device to detect
an ambient operating temperature of the conveying system, and is
connected to a low-speed operation switch 26. The first notify
device 30a notifies an estimated time that the amount of
displacement of the conveying belts 21a and 21b falls within given
limits and the belt is stabilized. The second notify device 30b
notifies the states that the amount of displacement of the
conveying belts 21a and 21b detected by the detection sensor 27, or
the amount of displacement of the conveying belts 21a and 21b, is
over a predetermined value, improved, and falls within given
limits, respectively. The first and second notify devices 30a and
30b make notification by displaying letters or by sounds.
[0055] After assembling the apparatus or after
maintenance/replacement of the conveying belt, or when operating at
a low temperature or when restarting after stopping the conveying
belt for a certain period, the control device 29 operates the
conveying motor 25 at a low speed for a certain time. After this
low-speed operation, the control device variably controls the
speeds of the conveying motor 25 and the conveying belts 21a and
21b according to the amount of displacement of the conveying belt
21 detected by the detection sensor 27, as described later in
detail.
[0056] Explanation will known be given on the operation of the
conveying motor 25 after assembling the apparatus or after
maintenance/replacement of the conveying belt, or after installing
a new conveying belt.
[0057] First, close the door 10a, and manually depress the
low-speed operation switch 26. The control device 29 operates the
conveying motor 25 at a low speed as a trial run, and gradually
increases the speed by monitoring the positions, displacement and
meandering of the conveying belts 21a and 21b through the detection
sensor 27, and makes automatic and quantitative adjustment to
familiarize the conveying belt to the conveying system.
[0058] Namely, after the conveying belts 21a and 21b are moved at a
low speed by the conveying motor 25, the amount of displacement of
the conveying belts 21a and 21b is detected by the detection sensor
27. In this time, when the amount of displacement of the conveying
belt 21b is large, for example, as shown in FIG. 7A, the control
device 29 controls the speed of the conveying motor 25 to a low
speed, as shown in FIG. 8A. As the amount of displacement of the
conveying belt 21b is improved as shown in FIG. 7B by this
low-speed operation, the speed of the conveying motor 25 is
increased as shown in FIG. 8B. When the amount of displacement of
the conveying belt 21b falls within given limits and the conveying
belt is stabilized by this low-speed operation as shown in FIG. 7C,
the speed of the conveying motor 25 is increased to a normal
operation speed as shown in FIG. 8C.
[0059] While the conveying belts 21a and 21b are moving, the first
notify device 30a notifies an estimated time that the amount of
displacement of the belts 21a and 21b falls within given limits.
This estimated time is determined based on the past data and the
changes in the amount of displacement of the conveying belts 21a
and 21b detected by the detection sensor 27.
[0060] Further, the second notify device 30b notifies the amount of
displacement of the conveying belts 21a and 21b at the present
time, for example, the states that the amount of displacement of
the conveying belts 21a and 21b is over a predetermined value,
improved, and falls within given limits.
[0061] Since the adjustment to familiarize the conveying belts 21a
and 21b to the conveying system is made automatically and
quantitatively as described above, the belts can be securely
familiarized with less variations, compared with the conventional
adjustment by the operator's sense and experience.
[0062] Next, an explanation will be given on the operation of the
conveying motor 25 in normal operation mode, not immediately after
assembling the apparatus or after maintenance/replacement of the
conveying belt.
[0063] The sensor 28 detects an ambient operating temperature at
startup of the conveying motor 25. When the detected temperature is
lower than a specification range as shown in FIG. 9A, operate the
conveying motor 30 at a low temperature for a certain time as a
trial run as shown in FIG. 10A.
[0064] When the temperature in the machine is increased to higher
than the lower limit of a specified ambient temperature range as
shown in FIG. 9B, gradually increase the speed of the conveying
motor 25 as shown in FIG. 10B. When the ambient operating
temperature is increased to within a specified range by this
operation, increase the speed of the conveying motor 25 up to a
normal operation speed as shown in FIG. 10C.
[0065] In the low temperature state, as described above, a trial
run is performed at a low speed, and the speed is gradually
increased, and the startup motor speed for starting the conveying
belt is controlled to optimum. This prevents displacement or coming
off of the conveying belt, and prevents a paper jam.
[0066] FIG. 11 is a block diagram showing a drive control system of
a conveying belt according to a second embodiment of the
invention.
[0067] The same components as those of the first embodiment are
given the same reference numerals, and detailed explanation of the
components will be omitted.
[0068] In the second embodiment, there are provided a first
measuring device 31 to measure the time passed after installation
of a conveying belt, a second measuring device 33 to measure a
cumulative operating time of the conveying motor 25, and a third
notify device 35 as a third notify device to notify a replacement
period of the conveying belt 21.
[0069] In the second embodiment, a replacement period of the
conveying belt 21 is notified before the life of the belt is
expired, based on the cumulative operating time of the conveying
motor 25, the time passed after installation of the conveying belt,
and the results of detection of the amount of displacement of the
conveying belt, a paper jam caused by the end of the life of the
belt.
[0070] For example, as shown in FIG. 2A, the cumulative operating
time of the conveying motor 25 and time passed after installation
of the conveying belt are measured, and if the conveying system is
judged not to have been operated for a certain period based on the
measurement data, automatically operate the conveying motor 25 at a
low speed for a certain time, and gradually increase the motor
speed, so that the amount of displacement of the conveying belt 21
falls within a specified range of UL-UL as shown in FIG. 13A.
[0071] When the conveying system has been continuously operated and
the conveying belt does not reach the end of its life as shown in
FIG. 12B, the amount of displacement of the belt is within the
specified range (UL-UL).
[0072] However, when the cumulative operating time of the conveying
motor 25 is long and the conveying belt 21 is going to reach the
end of life as shown in FIG. 12C, the conveying belt 21 expands and
largely zigzags as shown in FIG. 13C.
[0073] When the life of the conveying belt 21 comes close to the
end and the conveying belt 21 largely zigzags, the control device
29 judges it timing of replacing the belt, and the third notify
device 25 notifies to replace the conveying belt.
[0074] According to the second embodiment, when the conveying
system has not been operated for a certain period, the system is
automatically operated at a low speed as a trial run and the motor
speed is gradually increased, and the conveying belt is prevented
from displacing or coming off, and a paper jam is prevented.
[0075] When the life of the conveying belt comes close to the end,
it is notified to the third notify device 35, and the conveying
belt can be replaced before the life is expired, and a paper jam is
prevented.
[0076] FIG. 14 is a block diagram showing the drive control system
of a conveying belt according to a third embodiment of the
invention.
[0077] The same components as those of the first embodiment are
given the same reference numerals, and detailed explanation of the
components will be omitted.
[0078] In the third embodiment, there are provided a jam detection
sensor 37 as a jam detection device to detect a paper jam, and a
display unit 39 to display a first paper sheet causing a paper
jam.
[0079] When a paper jam is detected by the jam detection sensor 37,
the control device 29 displays a first paper sheet causing a paper
jam, in the display unit 39.
[0080] The operator watches the display 39, opens the door 100a of
the main body, and eliminates the jammed paper sheet. When the door
100a is opened, the safety switch 41 is turned on, and the power of
the conveying roller system is turned off, thereby ensuring the
safety. Leave the paper sheets other than the one causing the paper
jam stayed on the conveying path as they are, and close the door
100a. The reset switch 43 is depressed, and the detection sensor 27
detects the position of the conveying belt after the paper jam,
displacing or coming off, if any, and issues a corrective
instruction, if there is any problem.
[0081] When the position of the belt, displacing or coming off is
not detected by the sensor 27, start the conveying belt 21 at a low
speed, and convey the paper sheets stayed on the conveying path to
the stacking box, while checking the belt for meandering.
[0082] When the detection sensor 27 detects that the conveying belt
21b comes off after a paper jam, as shown in FIG. 15, the control
device 29 does not operate the conveying motor 25 as shown in FIG.
16A. If the conveying motor 25 is operated while the conveying belt
21 is coming off or being largely displaced, a serious secondary
paper jam may occur, and the conveying belt 21 may be broken. The
conveying motor 25 is not operated to prevent such a serious
trouble.
[0083] When the detection sensor 27 detects that the conveying belt
21 does not come off the roller 22, start the conveying motor 25 at
a low speed as shown in FIG. 16B, and gradually increase the speed
of the conveying motor 25 after the displacement of the conveying
belt is improved as shown in FIG. 17B.
[0084] When the amount of displacement of the conveying belt 21
falls with given limits as shown in FIG. 17C, increase the speed of
the conveying motor 30 to a normal operation speed as shown in FIG.
16C.
[0085] As described hereinbefore, according to the embodiment of
the invention, assembling and maintenance of the apparatus can be
safely performed with the door 100a closed. Besides, the positions,
displacement and zigzag movement of the conveying belts 21a and 21b
are monitored by the detection sensor 27. Therefore, the low-speed
trial run time and the rising curve when increasing the speed can
be optimally controlled.
[0086] Further, when the apparatus is operated at a low temperature
or not operated for a long time, start of the conveying motor 25 is
automatically controlled to a low speed, and the conveying belts
21a and 21b are familiarized to the conveying system. This
stabilizes the conveying performance.
[0087] Moreover, displacing and meandering of the conveying belts
21a and 21b are self-diagnosed, and the maintenance/replacement
period is notified. Therefore, the symptoms of coming off of the
belt can be previously collected, a replacement notice can be
issued before the life of the belt is expired, and a paper jam can
be prevented.
[0088] If a paper jam should occur, the operator can clear the
paper jam simply by opening the door 100a, removing a first paper
sheet causing the jam, and closing the door 100a. The operator can
automatically startup the apparatus while self-diagnosing the
displacement and zigzag movement of the belt. This improves the
operability.
[0089] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims and their equivalents.
* * * * *