JPH09111596A - Prevention of weaving bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep the warp tension at each opening frame at a level appropriate for preventing each weaving bar when a loom is halted. SOLUTION: In an opening control unit 3 designed to make position control of plural opening frames by the corresponding motors 4 independent of one another based on a specified opening pattern in such a mode as to be synchronized with the main shaft 22 of a loom, a target warp tension effective for preventing weaving bar. When the loom is halted is set in advance for each of the opening frames. Then the loom is halted, each of the motors 4 is switched from the position control of the synchronous mode with the main shaft 22 into torque control and the motor 4 is driven by driving current corresponding to a warp tension. By the torque of the motor 4, each of the opening frames is driven independently to ensure a warp tension corresponding to each of the opening frames to be kept at the target level.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric shedding device for a loom, and more particularly to a warp thread tension control method effective for preventing a weft bar when the loom is stopped.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 54-106661 discloses loosening the warp tension when the loom is stopped, as a technique for controlling the tension when the loom is stopped.
Japanese Patent No. 8640 discloses that the tension of the warp yarn when the loom is stopped is stored and the warp tension of the warp yarn is maintained during the stop. According to these techniques, since the opening amount differs for each opening frame, it is not possible to make the warp yarns even.

On the other hand, Japanese Patent Laid-Open No. 3-193952 discloses that
As the weaving bar preventing means, at the time of starting the loom, the warp thread is set to the maximum opening state to increase the tension of the warp thread so that the warp thread is pulled up, and then the warp thread is closed to lower the tension of the warp thread, It is disclosed that the operation is performed after the warp yarn elongation is suppressed. There is also a suggestion that this warp thread tension can be performed only by the opening device.

In Japanese Utility Model Laid-Open No. 4-33676, when the loom is restarted, in order to increase the tension of the warp thread which is not tensioned when the loom is stopped, the corresponding heald is moved and the opening amount is set to a higher value. After making the warp thread amount equal to the whole and making the warp thread even over the entire length, synchronize the opening and restart, and conversely make the opening amount the same as other low tension warp thread opening amounts. Discloses that the opening amount is selected according to the opening step when the loom is restarted.

According to the above technique, it is not possible to prevent the warp yarn from stretching when the loom is stopped. If a high tension is applied and the vehicle is stopped for a long time, the warp thread will be fully stretched, and no matter what operation is performed thereafter, the decrease in the tension of the warp thread caused by the fully stretched warp thread will not be resolved, and eventually a weaving bar will be generated. .

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a shed control device for an electric shedding device of a loom by keeping the warp tension of each shed frame at a tension suitable for preventing wefts when the weaving machine is stopped. The purpose of this is to prevent the occurrence of a weaving bar due to the difference in the tension of each warp thread.

[0007]

In view of the above object, the present invention relates to a shed control device for controlling the position of a plurality of shed frames in a state of being synchronized with a main shaft of a loom by an independent motor based on a predetermined shed pattern. The target tension of the warp yarn effective for preventing the weft bar is set in advance for each opening frame, and when the loom is stopped, each motor is switched from the position control in the synchronous state with respect to the main shaft to the torque control of each motor, and according to the target tension. By driving the motor by the driving current and independently driving the opening frame by the torque of the motor, the tension of the warp thread corresponding to each opening frame is maintained at the target tension value. Here, the target tension is set by calculation or actual measurement according to the drive mechanism of the opening frame.

[0008]

Before operation of the loom, the opening pattern during operation, the target tension of the warp thread for each opening frame in standby after the loom is stopped, and other data necessary for control are set and stored in the opening control device. It Here, the shed pattern means a target rotation amount of a motor for driving the shed frame with respect to the main shaft of the loom.

During operation of the loom, the shedding control device obtains the target rotation amount of the motor for driving each shed frame from the preset shedding pattern and the detected rotation angle of the weaving machine spindle, and the predetermined rotation amount is obtained. Thus, the rotation amount of the motor is controlled by the position control.

When a standby command is input after the loom is stopped,
The shedding control device switches the position control for the main shaft of the loom from each motor to torque control for each motor, that is, tension control for the warp thread, and then obtains the target tension calculated based on preset control data. Is output, and the motor is driven by the drive current corresponding to this torque to maintain the tension of the warp thread corresponding to each opening frame at the target tension value.

In this way, the tension of the warp threads is set and maintained at the target tension for each opening frame during the standby after the loom is stopped. As a result, for example, if the target tensions of the respective opening frames are set to be the same, the warp yarns are evenly stretched, so that the occurrence of a weft bar at the time of subsequent restart can be prevented.
The target tension of the warp thread is set according to at least one of the shedding step, the cause of the loom stoppage, the stoppage time, the opening direction during standby, and the yarn type.

When the stand-by command is canceled by the input of the mouth-matching command or the restart command, the shedding control device cancels the tension control and then executes the position control for the rotation angle of the main shaft of the loom again. Return the aperture frame to the proper amount of aperture for the main axis. The target tension of the warp thread to be set may be set to the same value for all repeats, or may be changed by the opening step.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows an outline of an electric opening device 1. The electric opening device 1 includes an opening control device 3 for each of the six opening frames 2. Each opening control device 3 rotates a crank mechanism as a drive mechanism, that is, a crank 5 by a built-in opening frame driving motor 4, and vertically moves each opening frame 2 through a connecting rod 6. A plurality of warp threads 9 are given an opening movement via a heald 8 attached to the opening frame 2. The drive mechanism can be configured by a rack and pinion mechanism, a cam mechanism, or the like, in addition to the crank mechanism.

Next, FIG. 2 shows the opening control device 3, and FIG. 3 shows a main part inside the opening control device 3. In these figures, when the operation command d or the standby command e is input to the opening command means 10, the operation command discriminator 11
Discriminates the content of the command, operates the cycle number indicator 12 at the time of the operation command d, causes the switch 38 to perform the switching operation at the time of the standby command e, and again when the standby command e is released. While operating the number commander 12,
The switching device 38 is caused to perform the switching operation again.

When the operation command d is input to the opening command means 10 for the operation of the loom, the cycle number indicator 12 reads the opening step x stored in the storage unit 13 and reads the next opening. The signal corresponding to step y is sent to the aperture selection pattern generator 16 inside the aperture pattern designating means 15. Here, the aperture selection pattern generator 16
Is the rotation angle θ of the loom detected by the encoder 23 connected to the main shaft 22 of the loom.
Aperture selection pattern Kp corresponding to the cycle during repeat
And the cycle number n are output, and the opening pattern setting device 18
In addition to the above, the cycle number n is also sent to the storage device 13 to update the stored opening step x.

The aperture pattern setter 18 sends a signal of the aperture pattern Ksi to the position command section 24. Here, the position command unit 24 determines the main shaft 22 of the loom based on the signal of the rotation angle θ from the encoder 23 connected to the main shaft 22 of the loom.
A signal of the target rotation amount Po is generated in a state of being synchronized with the rotation of, and is sent to the deviation detection unit 27 inside the drive control unit 26 via the OR gate 25. The deviation detection unit 27 compares the signal of the rotation amount Pf from the encoder 31 connected to the motor 4 with the signal of the target rotation amount Po, and calculates the deviation rotation amount Δ.
The signal of p is sent to the speed control unit 28.

The speed control unit 28 includes a base speed setter 17
The signal of the base speed Vo from is input, and the output in the direction of eliminating the deviation is generated while comparing this signal with the signal of the speed Vf for feedback from the encoder 31 provided coaxially with the motor 4. Then, this is supplied to the current control unit 29 via the switch 38. The base speed setting device 17 inside the opening pattern setting means 15 inputs the signal of the rotation angle θ and the signal of the opening pattern Ksi and sets the base speed Vo according to the rotation angle θ and the opening pattern Ksi.

The current controller 29 controls the drive current Im of the motor 4 detected by the current detector 30 and the deviation rotation amount Δp.
Also, the motor 4 is driven while comparing it with a target current given based on the feedback speed Vf of the motor 4. As a result, the motor 4 rotates in the direction of eliminating the deviation at a predetermined speed and current, and transmits the rotational force to the crank 5 via the gear 32. A phase detector 42 for detecting a crank phase is connected to the crank 5, and the phase detector 42 is used for the torque signal generator 3.
9. Output the crank phase ω to the opening direction command device 33.

When the cause q of the stoppage occurs during the operation of the loom, the loom enters a stopping operation, and after completely stopping, the loom reverses at a predetermined phase and enters a standby state. After that, a standby command e1 is issued from the loom controller (not shown) to the opening direction commander 33.
Is output to This opening direction command device 33 is based on a preset rule such as an algorithm and the phase signal of the motor 4 that drives each opening frame, in other words, the phase signal ω of the crank 5, based on the opening signal during torque control. The direction is determined and the opening direction signal f is supplied to the torque signal generator 39 of each opening control device.
Output to Then, after a certain period of time has passed, a standby command e is output from the loom control device (not shown) to the shedding command means 10. When the standby command e is input, the opening command means 10 switches the input of the switch 38 and operates the torque signal generator 39. At this time, the torque signal generator 39 drives the corresponding motor 4 with a predetermined target current Io to execute torque control on the motor 4 to change the position of the opening frame 2 and change the output torque of the motor 4. The tension control of the warp thread 9 is executed.

The opening direction commanding device 33 can judge each opening frame opening phase ω and act so as to prevent the movement of the cloth fell in the standby state. For example, when the opening state at the time of outputting the standby command e1 is the upper mouth opening and the number of frames of the lower mouth opening is unbalanced and there is a difference in tension between the upper thread and the lower thread, the number of frames is adjusted so that the tension difference is eliminated. Based on the set and preset algorithm, the opening phase ω of each opening frame when the standby command e1 is output is read and an appropriate opening direction command signal is output. More preferably, the number of frames should be set to the same number.

FIG. 4 shows an example in which the torque signal generator 39 comprises a calculator 34 such as a CPU, a setter 35 connected to the calculator 34, a memory 36, and a timer 37 for updating the stoppage time. In the setter 35, the target tension Ts as tension data, the cloth weave x1, the warp thread feeding point x2, the position x3 of the heald as position data, the weight Fm of the opening frame as weight data, the diameter r of the crank 5 as mechanism data, and the time of closing. The crank phase ωo, the connecting rod length L1 and the like are input. When the drive mechanism is a rack and pinion mechanism, the outer diameter of the gear is set, and when the drive mechanism is a cam mechanism, the effective diameter of the cam and the pressure angle are set.

These data are given to the calculator 34 via the setter 35 and stored in the memory 36. In addition to the standby command e, the signal of the cycle number n, and the cause of stop q, the calculator 34 outputs the signal of the stop time update m output from the stop time update timer and the opening direction output from the opening direction commander 33. The drive torque T of the motor 4 corresponding to the target tension Ts of the warp yarn is calculated by inputting the signal of the command f, the crank phase ωo at the time of closing, the crank phase ω, etc., and the target current Io corresponding to the value of this drive torque T is calculated. Is output to the current controller 29 via the switch 38. Then, the calculator 34 detects the current Im being output by the current detector 30, compares the target current Io corresponding to the drive torque T with the current Im, and eliminates the current deviation as the difference between the two. Perform current control. This current control is torque control for the motor 4, and is ultimately tension control for the warp thread 9 of the opening frame 2 corresponding to the motor 4.

FIG. 5 is an explanatory diagram showing the relationship between the drive system and the warp thread tension. The calculation formula of the motor torque T corresponding to the warp target tension is calculated in the following order. Target tension Ts of warp thread
At the time of setting, the acting force Fx in the vertical direction of the opening frame 2 is obtained by the following relational expression. Fx = F1 (L2, Ts, x1, x2, x3)

The driving torque T of the motor 4 required to generate the acting force Fx is calculated by the following relational expression. The drive torque T of the motor 4 is a torque value at the position of the crank 5 for convenience, not at the position of the output shaft of the motor. However, if the crank phase ω is not required due to the drive mechanism,
Omit it. T = F2 (Fx, Fm, ω)

From these, by substituting the relational expression for obtaining Fx into the driving torque T, the following relational expression is obtained. T = F2 (F1 (L2, Ts, x1, x2, x3), F
m, ω)

Incidentally, the opening amount L2 may be detected by directly measuring it, but it can be calculated by the motor rotation amount α from the crank phase ωo when the drive mechanism closes. However, α = ω−ωo.

Crank mechanism → L2 = F3 (α, r, L1) Rack and pinion mechanism → L2 = F3 (α, r) Therefore, when this formula is substituted into the drive torque T of the crank mechanism, the drive torque T is It is calculated by the following relational expression. T = F2 (F1 (F3 (ω−ωo, r, L1), Ts,
x1, x2, x3), Fm, θ)

As a result, the drive torque T can be calculated from the crank phase ω and the target tension Ts of the warp thread. In reality, it is desirable that after setting the target tension Ts, all the driving torques T corresponding to the crank phase ω are calculated, then temporarily stored in the memory 36, and the driving torque T corresponding to the crank phase ω is read when necessary. . Of course, these relationships can also be set by actual measurement. In addition,
Although the crank phase ω is detected by the crank phase detector 42, the rotation amount Pf from the encoder 31 coaxial with the motor 4 can be used as a substitute.

When the stand-by command e is canceled by the input of the aligning command after the yarn repair or the restart command, the opening command means 10 cancels the tension control and executes the position control again. At that time, first, the operation command discriminator 11 operates the movement amount setting device 20 and the pulse oscillator 21 inside the movement command means 19. The movement amount setter 20 replaces the position command unit 24 during normal operation with the opening pattern Ksy for synchronous restart in order to synchronize and continue the opening motion before the occurrence of the stop cause q when restarting. Signal and rotation angle θ
Is input to generate a signal of the set rotation amount Ps and send it to the pulse oscillator 21.

In this way, the pulse oscillator 21 generates the output of the number of pulses corresponding to the set opening amount Ps and sends it to the drive control unit 26.

FIG. 6 shows the operation sequence of the aperture control device 3. First, opening data for each opening frame 2 during operation, tension data during waiting after stopping, and other necessary data are input in relation to the rotation angle θ for each cycle of one repeat, and opening pattern setting is performed. Bowl 18
Or to the torque signal generator 39 or the like.

In this state, when the operation command d is given by the operation of the operation button (not shown), the loom is in the continuous operation state, and the shedding command means 10 and the shedding pattern designating means 15 are synchronized with the rotation of the main shaft 22. In this state, by giving a signal of the opening pattern Ksi to the position command section 24, the six opening frames 2 are sequentially driven according to the opening pattern Ksi, and the warp thread 9 is given a predetermined opening movement.

In FIG. 8, (1) is six (No. 1, 2, ...
.. The opening pattern is shown for the opening frame 2 in 6) in relation to the weft insertion cycle and the opening cycle. In this way, each opening frame 2 imparts a predetermined opening movement to the warp thread 9 by repeating the vertical movement in a predetermined order in each cycle of three rotations and one repeat in accordance with the fabric structure.

In addition to FIG. 6, as shown in (2) of FIG. 8, when the stop cause q occurs during the continuous operation, for example, in the weft insertion cycle (n + 1), that is, the opening cycle (n + 2),
Since the signal is given to the loom controller not shown,
The loom controller brakes the main shaft 22 of the loom, and after the braking rotation time, stops the main shaft 22 of the loom at, for example, 240 degrees in the next opening cycle (n + 3), and then automatically reverses the opening and opens. Return to cycle (n + 2)
Is a standby angle θ that is a reverse rotation stop angle of about 300 degrees, for example.
After reversing to s for a standby state, a standby command e1 is given to the opening direction command device 33 and a standby command e is given to the opening command means 10.

When the standby command e is input, the opening command means 10 switches the switch 38 from the input state for the speed control unit 28 to the input state for the torque signal generator 39, and the torque signal is generated by the position control for the main shaft 22. Bowl 3
Set the tension control mode according to 9. The torque signal generator 39 reads the cycle number n, the opening direction command f, and the crank phase ω, and according to these conditions, the target tension Ts.
Target current Io necessary for generating the current is generated, and the current Im from the current detector 30 is compared with the target current Io while rotating the motor 4 via the current control unit 29 to obtain a predetermined current value. Adjust.

Therefore, the rotation output of the motor 4 at this time generates the driving torque T for giving the target tension Ts. The drive torque T as the output of the motor 4 moves the corresponding opening frame 2 in a predetermined direction via the crank mechanism, and the warp thread 9 held in the heald 8 of the opening frame 2 by the force in the moving direction. A target tension Ts is given to. Therefore, after the standby command e is input, the warp thread 9 corresponding to each opening frame 2 is set to the target tension Ts. If these series of operations are performed continuously or repeatedly at fixed time intervals, the accuracy is further improved. This is because the acting force on the opening frame 2 and the warp thread tension change depending on the opening amount, in other words, the crank phase ω.

The target tension Ts is appropriately set by setting a value obtained from past experience, or by actually observing warp yarn elongation and weaving bar condition. It is also possible to set different values for each opening frame. For example, the tension can be set according to the type of warp yarn, and the elongation of the warp yarn can be made uniform with respect to a special weaving structure.

The target tension Ts may be changed according to the shedding step and the shedding direction of the loom. By doing this, the elements related to the opening step (amount of opening when stopped, opening direction)
It is possible to take countermeasures by changing the tension of the weaving bar generated in. In addition, the set value may be changed depending on the cause of the loom stop and the stop time. Countermeasures can be taken by changing the tension for the cause of stoppage and the loom generated during stoppage time. in this regard,
It will be described later together with FIG. 7.

FIG. 8 (1) shows the opening pattern of each opening frame 2 and the warp position of the opening frame 2 when the tension is controlled by stopping at the opening cycle (n + 2). In this case, the opening direction command device 33 described above acts and N
o. The three opening frames 2 of Nos. 1, 3, and 6 are open to the upper side, and the remaining No. The three opening frames 2 of 2, 4, 5 are set to open downward. In this way, each opening frame 2 is in the standby state at the opening position corresponding to the target tension Ts for the warp thread 9.

When the stop cause q is warp thread breakage or another cause of stop, the warp thread breakage is repaired and the cause of stoppage is removed, and when the operation, inching, reverse rotation button, etc. are operated, the standby command e is turned off. It becomes the state of. Therefore, the opening command means 1
When 0, the switch 38 is switched to stop the tension control, the output from the speed controller 28 is sent to the current controller 29, and the position control is returned to the opening pattern Ksy from the opening pattern setter 18. By operating the movement amount setting device 20, the opening phase (opening step x, y) is returned to the phase when the stop cause occurs, that is, the opening cycle (n + 2), and the opening pattern designating means 15 is moved to the normal position control mode. Set to.

On the other hand, if the cause q of the stop is a misinsertion error, the reverse button is operated to release the standby commands e and e1 and return to the position control mode as described above.
After phasing as described above, the weaving machine is operated in the shedding cycle (n +
Reverse the open state in 2) to the weft insertion cycle (n
The defective weft yarn of (+1) is removed, the loom is further reversed to the operation start position which is the opened state of the previous shed cycle (n + 1), and the operation button is pressed to restart the loom. During this time, the opening control device 3 gives an opening operation to the plurality of opening frames 2 in a state of being synchronized with the rotation of the main shaft 22.

FIG. 7 shows a flowchart for changing the driving torque T (target tension Ts) according to the elapsed stop time during the stand-by time in the standby state,
Is the set time elapsed after outputting the initial drive torque T? Is determined, and when the set time has elapsed, the initial drive torque T is usually set.
If the set drive time T is output and the set drive time T has not elapsed, the set drive time T has elapsed? It returns to the judgment step of.
Then, when the standby command e is turned off, the change of the drive torque T is completed.

In the above embodiment, the tension control of the shed frame is executed from the time the loom is in the standby state until the thread breakage repair is started, but it may be always executed while the loom is stopped. For this purpose, the calculator 34 in the torque signal generator 39 is provided with a spindle rotation angle signal θ from the encoder 23 and an opening pattern Ks from the opening pattern designating means 15.
Is entered. When the thread breakage repair is started and the standby command from the opening command means 10 is released, the torque signal generator 39 causes the drive current Io to be supplied to the spindle based on the target tension set according to the spindle rotation angle θ. Output according to the rotation angle θ. As a result, for example, when a weft insertion error occurs, when the weaving machine is rotated in reverse to remove the weft insertion error yarn, the shed frame is driven based on the tension set according to the spindle rotation angle θ. When the weft insertion error yarn is removed and the loom is operated, the opening frame is returned to the position control corresponding to the spindle rotation angle θ. Further, for example, when selvage yarn breakage occurs, even if the yarn breakage repair work is started and the yarn breakage repair work after moving the bobbin in which the yarn breakage has occurred to a phase in which it is easy to repair may take time in advance. Tension control is executed based on the tension set according to the spindle rotation angle θ and the repair time. The repair time is the elapsed time from the start of repair work. As described above, it is also possible to prevent warp yarn unevenness by controlling the tension based on appropriate tension settings according to various parameters such as the spindle rotation angle θ and the repair time.

[0044]

[Other Embodiments] The embodiment of FIG.
A load sensor 40 such as a strain gauge is provided between the opening frame 2 and the connecting rod 6, and the load sensor 40 and the amplifier 4 are provided.
1 is an example in which the acting force F is measured as an electric quantity by 1, and the acting force Fx of the opening frame 2 is indirectly measured from this, and the tension control is performed on the warp thread 9 of the opening frame 2 by using this as a feedback signal. Then, the acting force F of the opening frame 2
Since x is actually measured and the actual warp thread tension is accurately grasped and the motor drive current Io is calculated, more accurate tension control can be executed.

[0045]

According to the present invention, the warp thread tension can be freely set during the stand-by after the loom is stopped, regardless of the shed pattern during the loom operation, so that the warp threads are prevented from moving and the warp threads are evenly stretched. This makes it possible to effectively prevent the stop stage. In particular, since the tension of the warp thread can be set for each opening frame, it is possible to set the tension according to the thread type of the warp thread.
The stop stage can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of an electric opening device.

FIG. 2 is a block diagram of an aperture control device.

FIG. 3 is a block diagram of an opening instruction unit, an opening pattern designation unit, and a movement instruction unit;

FIG. 4 is a block diagram of a torque signal generator.

FIG. 5 is an explanatory diagram of a relationship between crank torque and thread tension.

FIG. 6 is a flowchart of the operation.

FIG. 7 is a flow chart when changing the thread tension depending on the stop time.

FIG. 8 (1) is an explanatory view of the opening movement patterns of the six opening frames for the weft insertion cycle and the shed cycle, and (2) is the operation, stop, reverse rotation, standby, warp repair of the loom or It is explanatory drawing of the operation sequence leading to the restart after the horizontal insertion repair. Further, the above (1) and (2) correspond up and down by the rotation angle θ.

FIG. 9 is a block diagram of an opening control device according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric opening device 2 Opening frame 3 Opening control device 4 Motor 5 Crank 9 Warp thread 10 Opening command means 15 Opening pattern designating means 19 Movement command means 22 Spindle 23 Encoder 24 Position command section 26 Drive control section 33 Opening direction commander 38 Switcher 39 Torque signal generator 40 Load sensor

Claims (1)

[Claims] 1. An electric shedding device for driving a plurality of shed frames by independent motors, wherein the shed control device controls the positions of the respective shed frames in synchronism with the main shaft of the loom based on a predetermined shed pattern. The target tension of the warp yarn, which is effective in preventing the weft bar at that time, is set in advance for each opening frame, and when the loom is stopped, each motor is switched from the position control in the synchronous state to the main shaft to the torque control of each motor, and the target tension is set. A weaving bar preventing method characterized in that a warp thread tension corresponding to each opening frame is maintained at a target tension by driving a motor with a corresponding drive current and independently driving the opening frame with the torque of the motor.