BACKGROUND OF THE INVENTION
Field of the Invention:
[0001] The present invention relates to an operation control system for a plurality of single
spindle driving spinning machines, each spinning machine being of the type in which
the machine is mounted with a large number of spindles and in which the spindles are
independently driven by motors provided in the spindles, respectively.
Description of the Related Art:
[0002] For the purpose of making it possible to set a large number of spindles in a spinning
frame, or to increase the rotational speed of the spindles, a single spindle driving
spinning machine has been recently proposed which has, instead of only one motor for
driving all spindles in a spinning frame, a plurality of spindle driving motors for
driving the spindles, respectively. As a method of controlling spindle driving motors
in the single spindle driving spinning machine, a method of driving and controlling
spindle driving motors by one inverter is disclosed in Japanese Patent Application
Laid-open No. 10-226930. Further, a method of independently driving and controlling
respective spindle driving motors by individual inverters is disclosed in Japanese
Patent Application Laid-open No. 11-181636, along with an arrangement in which information
about a broken-state of thread in each spindle is handled in a control device provided
in a frame.
[0003] A spinning machine in which a large number of spindles are driven by one motor cannot
perform operation of the frame, due to its construction, in a state in which a specific
spindle is at rest. Thus, the degree of freedom in an operation control of the frame
is low. On the contrary, in the case of a single spindle driving spinning machine,
spindles can be driven independently, and thus it is possible to perform the operation
of the frame in a state that a specific spindle is at rest. Accordingly, the degree
of freedom in an operation control of the frame is high. Conventionally, in such a
spinning machine for driving a single spindle, a proposal has been made concerning
an operation control of each frame based on, for example, information about a broken-state
of thread, but no proposal has been made concerning an operation control of a plurality
of frames with efficiency.
SUMMARY OF THE INVENTION
[0004] The present invention has been made in view of the above, and an object of the present
invention is therefore to provide an operation control system for single spindle driving
spinning machines, which enables an operation of a plurality of single spindle driving
spinning machines with efficiency.
[0005] According to the present invention, there is provided an operation control system
for single spindle driving spinning machines, each of which is of the type in which
the machine is mounted with a plurality of spindles and the spindles are independently
driven by motors provided in the spindles, respectively,-characterized in that the
system comprises: a plurality of spindle computers which are provided in correspondence
with the plurality of spindles and each of which drives and controls a motor provided
in the corresponding spindle; a plurality of frame computers which are provided correspondingly
to the plurality of spinning machines and each of which is connected with the plurality
of spindle computers provided in the corresponding spinning machine through communication
means and controls operation of the corresponding spinning machine; and a host computer
which is connected with the plurality of frame computers through the communication
means and which keeps an operation conditions of each frame under control.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006]
Fig. 1 is a front view of a spindle in an embodiment;
Fig. 2 is a block diagram showing a spindle control device in the embodiment;
Fig. 3 is a block diagram showing a structure of an operation control system for single
spindle driving spinning machines in accordance with the embodiment; and
Fig. 4 is a block diagram showing a structure of an operation control system in accordance
with another embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0007] Hereinafter, an embodiment of a ring spinner according to the present invention will
be described.
[0008] As shown in Fig. 1, each spindle 1 of the spinner is provided with a driving spindle
motor 2. A synchronization motor is used as the spindle motor 2. A spindle control
device 4 is provided in a housing 3 of the spindle motor 2, and a power supply converted
from a commercial power supply into a direct current by an AC/DC converter (not shown)
is supplied to the spindle control device 4.
[0009] A display portion 10a for displaying a broken-state of thread and a display portion
10b for notifying abnormality are provided in each housing 3. These display portions
10a and 10b are disposed on a front surface of the housing 3 in parallel. Orange LEDs
are used in the display portion 10a, and red LEDs are used in the display portion
10b. Further, the housing 3 is equipped with a switch 11 for instructing the spindle
motor 2 to start/stop.
[0010] As shown in Fig. 2, the spindle control device 4 is provided with an inverter 5 and
a spindle computer 6 for controlling a spindle. The spindle computer 6 is provided
with a CPU 7 and a memory 8. Any one of three feeders for connecting the inverter
5 with the spindle motor 2 is provided with a current sensor 9 for measuring a current
supplied to the spindle motor 2. The CPU 7 inputs an output of the current sensor
9 through an A/D converter and an interface, which are not shown in the figure. The
CPU 7 obtains a rate of change of current in accordance with an output signal from
the current sensor 9, and when the rate of change of current exceeds a set value,
the CPU 7 judges occurrence of a broken-state of thread, and then stops supply of
power to the spindle motor 2 of the corresponding spindle and also turns on the display
portion 10a for displaying the broken-state of thread. Further, the spindle motor
2 is provided with a sensor (not shown) for detecting its rotational speed. In the
case where the rotational speed of the spindle motor 2, which is detected by the sensor,
largely deviates from a predetermined value, the CPU 7 judges that an abnormality
has occurred, and then stops the spindle motor 2 and also turns on the display portion
10b for notifying abnormality.
[0011] As shown in Fig. 3, all the spindles of the spinning frame is divided into a plurality
of groups, one group consisting of 48 spindles, for example. All the spindle computers
6 in each of the groups are connected with a section control unit 12 dedicated to
one of the groups through a communication line 13, respectively. The section control
unit 12 is connected with a frame control device 14 that unifies all the spindles
through the communication line 13. A multi drop connection using a serial interface
is adopted for the communication line 13, and RS-485 is used, for example, as the
serial interface. The section control unit 12 relay the transfer of signals between
the spindle computers 6 and the frame control device 14, which are connected with
the section control unit 12.
[0012] The frame control device 14 is provided with a frame computer 15 and an input device
16. The frame computer 15 is provided with a CPU 18, a ROM 19, a RAM 20, and an input/output
interface 21, and the input device 16 is connected with the CPU 18 through the input/output
interface 21. Further, a display 17 and a counter 22 for totalizing rpm of a front
roller (not shown) are respectively connected with the CPU 18 through the input/output
interface 21. The CPU 18 calculates the actual length of thread wound around a bobbin
of each of the spindles (referred to as actual spinning length) based on the count
value of the counter 22.
[0013] Program data and various data necessary for carrying out the program are stored in
the ROM 19. The program data includes corresponding data on spinning conditions such
as various fiber materials, spinning count and the number of twists, rotational speed
of a spindle at the time of steady operation, rotational speed of motors of a draft
driving system and a lifting driving system, and the like. The RAM 20 temporarily
stores the data input from the input device 16, the calculation processing result
at the CPU 18, and the like.
[0014] The CPU 18 inputs data on the broken-state of thread and abnormality of each spindle
in a predetermined cycle from each-of the spindle computers 6, and then calculates
the actual spinning length of each spindle based on the data and a detection signal
from the counter 22 and also totalizes the number of times of the broken-state of
thread every spindle. The RAM 20 is provided with a storage region for storing the
number of times of the broken-state of thread and a storage region for storing the
actual spinning length, which correspond to each spindle.
[0015] The CPU 18 totalizes the number of times of broken-state of thread and stores the
number in the storage region that corresponds to the spindle in which the broken-state
of thread occurs. Further, the CPU 18 stores the difference between the count value
of the counter 22 at the time of a stop due to the broken-state of thread or abnormality
and the count value of the counter 22 at the time of restarting of spinning for each
spindle. When the actual spinning length is calculated, the spinning length corresponding
to the stored difference of the count value is subtracted from the spinning length
obtained from the count value of the counter 22 at that time, thereby obtaining the
actual spinning length at that time. In the case where spinning is not restarted until
the time of the calculation of the actual spinning length, the spinning length until
the time of the stop corresponds to the actual spinning length. The CPU 18 totalizes
the number of times of the broken-state of thread of each spindle from the start of
operation of the frame until the stop of doffing (during one doff), and the integrated
value is reset to zero every one doff. The frame computer 15 can display various items
of control information (for example, a number and a position of the spindle with the
broken-state of thread and the spindle with abnormality) on the display 17 by the
operation of the input device 16.
[0016] Each of the frame computers 15 is connected with a host computer 24 through a local
area network (LAN) 23. The host computer 24 is provided with a CPU 25, a ROM 26, and
a RAM 27. The host computer 24 is connected with an input device 28 and with a color
display 29 through an input/output interface (not shown). The host computer 24 is
supplied with control data on information on broken-state of thread, actual spinning
length, or existence/non-existence of abnormality, or rpm of motor, current, voltage,
load state or the like from the frame computer 15. The information on broken-state
of thread includes information on whether each spindle is in the broken-state of thread
at present or not, and information on the total number of times of broken-state of
thread.
[0017] When the number of times of broken-state of thread exceeds a predetermined number
of times Nα set in advance in a predetermined period (during one doff in this embodiment)
in a certain spindle, the CPU 25 outputs a starting prohibition command signal for
prohibiting starting of the spindle motor 2 of the spindle to the corresponding spindle
computer 6 through the frame computer 15. The predetermined number of times Nα differs
depending on the spinning conditions, and is set to several times, for example. When
inputting the starting prohibition command signal, the spindle computer 6 turns on
the display portion 10b of the corresponding spindle and also does not start the spindle
motor 2 until a starting prohibition cancellation command signal is input even if
the switch 11 is turned on or a starting signal is input from the frame computer 15.
[0018] The host computer 24 can display various items of control information on the color
display 29 by the operation of the input device 28 and also can output the starting
prohibition cancellation command signal to the frame computer 15. The CPU 18 of the
frame computer 15 outputs a starting cancellation command signal to the spindle computer
6 of the corresponding spindle based on the starting prohibition cancellation command
signal.
[0019] Further, the host computer 24 transmits data for the frame operation on, for example,
the number of stop spindle in the adjustment of production and the spinning conditions
at the time of changing the spinning conditions. In addition, the host computer 24
can print various items of control data, a daily report, and the like from a printer
not shown in the figure.
[0020] Next, the operation of the system structured as described above will be described.
Prior to the operation of the spinning machine, the spinning conditions such as the
fiber material, the spinning count, and the number of twists are input to each of
the frame computers 15 from the host computer 24. Note that these spinning conditions
may be input from the input device 16 of the frame computer 15. When the operation
of the spinning machine is started, the speed command of the spindle motor 2 is output
to the respective spindle computers 6 of the respective spindles from the frame computer
15, and each of the spindle computers 6 controls the spindle motor 2 to a predetermined
rotational speed through the inverter 5 based on the command from the frame computer
15.
[0021] Each of the spindle computers 6 judges existence/non-existence of a broken-state
of thread and existence/non-existence of abnormality of the corresponding spindle
in a predetermined cycle. When the spindle computer 6 acknowledges the broken-state
of thread, it stops the spindle motor 2 and also turns on (drives) the display portion
10a. On the other hand, when the spindle computer 6 acknowledges the abnormality,
it stops the spindle motor 2 and also turns on (drives) the display portion 10b. The
spindle computer 6 outputs the existence/non-existence of the broken-state of thread
and abnormality to the section control unit 12.
[0022] The CPU 18 of the frame computer 15 inputs data on the existence/non-existence of
a broken-state of thread and the existence/non-existence of abnormality from the spindle
computers 6 of the respective spindles through the section control unit 12 in a predetermined
cycle. Further, the frame computer 15 calculates the actual spinning length of each
spindle. Then, the frame computer 15 outputs control information such as information
on a broken-state of thread to the host computer 24 during the operation in accordance
with the command from the host computer 24. After the stop due to the state of a full
spool, the frame computer 15 outputs data on the count value of the total number of
times of broken-state of thread and the actual spinning length of each spindle during
one doff to the host computer 24 before resetting the data to zero.
[0023] The host computer 24 retrieves the spindle in which the total number of times of
broken-state of thread exceeds the predetermined number of times Nα based on the control
data during the operation of the frame, judges that the corresponding spindle is a
spindle in bad condition, and outputs a starting prohibition command to the spindle
computer 6 of the spindle through the frame computer 15. Further, the host computer
24 calculates efficiency of each spindle and efficiency of each frame in accordance
with the actual spinning length of each spindle based on the control data every one
doff.
[0024] The host computer 24 notifies each of the frame computers 15 of the number of the
spindle to be stopped in carrying out a planned stop to stop a part of the frames
and spindles for the adjustment of production. In this case, the spindle or frame
with inefficiency is given priority in stopping.
[0025] After the repairing processing of the spindle in bad condition is completed by a
maintenance worker, this is reported to a manager. The manager operates the input
device 28 of the host computer 24 and outputs the starting prohibition cancellation
command signal to the spindle having been subjected to the repairing processing through
the frame computer 15. Thus, the drive and control of the spindle motor 2 of the spindle
is possible again. The manager displays the spindle in a starting prohibition state
on a screen of the color display 29 in canceling the starting prohibition. Then, the
manager selects the spindle in which the starting prohibition should be cancelled
and clicks the display of the spindle on the screen. Then, the starting prohibition
cancellation command to the spindle is output to the frame computer 15 to which the
spindle belongs, and the display of the spindle on the screen is cancelled.
[0026] When spinning is continued to reach the state of a full spool, the operation of the
frame is stopped. Then, a doffing operation is started by a doffing device (not shown).
The integrated value of the number of times of the broken-state of thread and the
actual spinning length of each spindle, which are stored in the RAM 20, are reset
to zero by a starting signal of the doffing operation. Note that, when the starting
prohibition cancellation command signal is output to the spindle in bad condition
in which repairing is completed, the total number of times of the broken-state of
thread of the spindle is reset to zero based on the command signal.
[0027] This embodiment has the following effects.
a) In the single spindle driving spinning machine, the spindle computers 6 provided
in the respective spindles and the frame computer 15 are connected through the communication
line 13. Each of the frame computers 15 and the host computer 24 that controls the
operation conditions of each of the frames are connected through the LAN 23. Therefore,
the transfer of data may be carried out easily among the respective computers. Thus,
division of the control is attained, thereby enabling the control with efficiency.
b) The broken-state of thread of each spindle is judged by each of the spindle computers
6, and the judgement results are output to the frame computer 15. Then, the control
data is output to the host computer 24 from the respective frame computers 15. Therefore,
it is possible to reduce collection time for data on the broken-state of thread, and
thus monitoring at higher speed is possible.
c) The respective spindle computers 6 are connected with the frame computer 15 through
the section control units 12. Therefore, when the frame computer 15 acquires data
of each spindle on broken-state of thread and the like by a polling method, the frame
computer 15 conducts polling plural times corresponding to the number of the section
control units 12, thereby making it possible to input data of all the spindles. Thus,
the data collection time can be further reduced.
d) The host computer 24 inputs the control data from the respective frame computers
15, thereby making it possible to control the operation conditions of all the frames
and controlling the judgement of the spindle in bad condition, the stop of the spindle
in bad condition, and the like with efficiency.
e) The frame computer 15 calculates the actual spinning length of each spindle based
on the data on the broken-state of thread from the respective spindle computers 6
and the detection signal from the counter 22 of the frame. Therefore, the host computer
24 inputs the data from the respective frame computers 15, and thus the output and
production efficiency of each spindle and each frame can be kept under control with
more precision.
f) The frame computer 15 is connected with the host computer 24 through the LAN 23,
and the cancellation of the starting prohibition command is possible by the command
from the host computer 24. Therefore, the worker does not have to cancel the starting
prohibition for each spindle at his discretion, and there is no fear that the control
of the host computer 24 is hindered.
[0028] The present invention is not limited to the above embodiment, and may be embodied
as described below, for example.
[0029] Without the provision of the section control units 12, the spindle computers 6 of
the respective spindle control devices 4 may be connected with the frame computer
15 of the frame control device 14 through a LAN 30 as shown in Fig. 4. Ehternet is
used as the LAN 30. In this structure, the data transfer is not carried out between
the frame computer 15 and the spindle computers 6 by conducting polling by the frame
computer 15, and data output is possible from the respective spindle computers 6 to
the frame computer 15. As a result, it is possible to further reduce the time that
the frame computer 15 requires for acquiring the data on existence/non-existence of
a broken-state of thread or abnormality of all the spindles.
[0030] As for the command for the same operation of the spindle computers 6 such as the
starting prohibition command, the starting prohibition command signal may be common
to the spindle computers 6 irrespective of the difference of reasons for the starting
prohibition.
[0031] Further, one or both of the frame computer 15 and the host computer 24 may compare
the total number of times of broken-state of thread and the predetermined number Nα
in one doff and judge the spindle in which the total number exceeds the predetermined
number Nα is a spindle in bad condition. Thus, the starting prohibition command may
be output to the spindle computer 6 of the spindle.
[0032] A method of detecting broken-state of thread of each spindle is not limited to a
method of detecting a supply current to the spindle motor 2 by the current sensor
9, and a sensor for detecting broken-state of thread of another method may be used.
[0033] The display condition may be changed, for example, the broken-state of thread and
the abnormality may be notified by using a combination of continuously turning on
a light and switching a light on and off by using one display portion, instead of
providing separately the display portion 10b for notifying abnormality and the display
portion 10a for displaying broken-state of thread. Thus, the number of components
is reduced, and the manufacturing cost can be reduced.
[0034] The period for totalizing the number of times of broken-state of thread for judging
whether a spindle is a spindle in bad condition or not may be set in a plurality of
doffs, working hours of a shift worker, or days instead of one doff as one unit.
[0035] The present invention is not limited to the ring spinner, and may be applied to a
ring throwing machine for driving a single spindle, and the like.
1. An operation control system for a plurality of single spindle driving spinning machines,
each spinning machine being of the type in which the machine has a plurality of spindles
and the spindles are independently driven by motors provided in the spindles, respectively,
said operation control system comprising:
a plurality of spindle computers provided in correspondence with the plurality of
spindles, respectively, each of which drives and controls a motor provided in the
corresponding spindle;
a plurality of frame computers provided in correspondence with the plurality of spinning
machines , respectively, each of which is connected with the plurality of spindle
computers provided in the corresponding spinning machine through a communication means
and controls an operation of the corresponding spinning machine; and
a host computer which is connected with the plurality of frame computers through another
communication means and which keeps operation conditions of each frame under control.
2. An operation control system according to claim 1 wherein
each of the spindle computers outputs data on the state of the corresponding spindle
to the corresponding frame computer;
each of the frame computers outputs speed command to the corresponding spindle computers,
also handles data input from the respective spindle computers and outputs the data
to the host computer; and
the host computer handles the data input from each of the frame computers.
3. An operation control system according to claim 1 wherein
each of the spinning machines is provided with a counter for totalizing rpm of a front
roller; and
each of the frame computers calculates an actual spinning length of each spindle based
on data on a broken-state of thread from the corresponding spindle computers and a
detection signal from the counter.
4. An operation control system according to claim 1 wherein the plurality of spindles
mounted on each of the spinning machines are divided into a plurality of groups, section
control units are provided in correspondence with the respective groups, and a plurality
of spindle computers of each of the groups are connected with the corresponding frame
computer through the corresponding section control unit.
5. An operation control system according to claim 4 wherein
each of the spindles is provided with a display portion for displaying a broken-state
of thread and a display portion for notifying abnormality; and
each of the spindle computers judges existence/non-existence of the broken-state of
thread and existence/non-existence of the abnormality of the corresponding spindle
in a predetermined cycle, when detecting the broken-state of thread, stops the corresponding
motor and also turns on the display portion for displaying the broken-state of thread
of the corresponding spindle, and when detecting the abnormality, stops the corresponding
motor and also turns on the display portion for notifying the abnormality of the corresponding
spindle.