JPH04333644A - Driving motor control unit for drum-type length-measuring reservoir in loom - Google Patents

Abstract

PURPOSE:To provide a control unit so designed that feed forward control is applied, at a correction control section, on a driving motor control system in response to condition signals given by a condition control section, thereby avoiding the response delay for the driving motor, leading to prevention of short pick developments. CONSTITUTION:In controlling a driving motor of a drum-type length-measuring reservoir in a jet loom, revolutions of a loom main shaft and those of the driving motor are compared with each other, a synchronous control section 10 equipped with a frequency divider operates the revolutional deviation to follow at a specified rate the revolutions of the driving motor to the main shaft revolutions; based on the result, the driving motor is put to revolutional control through a driving control section 20. In this case, a correction control section, 40 sets different frequency division ratios in response to the condition signals from a condition control section 30 to discriminate the loom's operational state, and based on the result, feed forward control is applied on either the synchronous control section or the driving control section equipped with both speed and current control systems to temporarily follow the driving motor's revolutions to those of the main shaft at a rate larger than that during stationary operation (e.g. in loom start-up), thereby effectively compensating the response delay for the driving motor.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive motor control device for a drum-type length measuring and storage device of a loom for effectively preventing the occurrence of short picks in a shuttleless loom such as a jet loom.

0002

2. Description of the Related Art In jet looms, drum-type length measuring and storage devices are often used to accurately measure the length of one pick of weft yarn and supply it to a weft insertion nozzle.

There are two types of drum-type length measurement and storage devices: a stationary drum type and a rotating drum type. Wrap it around and store it. The yarn is unwound from the drum at a predetermined time by a predetermined length corresponding to a predetermined number of turns by controlling a locking pin that moves forward and backward with respect to the surface of the drum, and is inserted as a weft. Can be done.

[0004] In order to support high-speed operation of the loom and multicolor weft insertion, the rotating yarn guide and rotating drum are often driven by a dedicated drive motor instead of being mechanically connected to the main shaft of the loom (for example, , Japanese Patent Publication No. 61-26663
Publication No. 9). In other words, the rotation amount of the main shaft and the rotation amount of the drive motor are detected, the rotation amount deviation is calculated to make the drive motor follow the main shaft at a predetermined ratio, and the drive motor is controlled to rotate based on this rotation amount deviation. By doing so, the drive motor rotates in accurate synchronization with the main shaft, and it is possible to accurately measure and store a predetermined length of yarn on the drum.

[0005] As the drive motor at this time, it is best to use a DC servo motor in order to achieve good controllability, and the thread on the drum is the minimum amount necessary for weft insertion for one pick. It is best to store only a limited amount. This is because if excess yarn is stored on the drum, the yarn may become tangled on the drum, which may prevent smooth weft insertion.

[0006]

[Problems to be Solved by the Invention] When using such conventional technology, the response of the drive motor is delayed when starting the loom, etc., resulting in an insufficient amount of yarn stored on the drum, and short picks may occur. There was a problem. In other words, the control system that controls the drive motor is generally
Since the control constants are set with top priority on controllability during steady operation of the loom, for example, when starting the loom,
When the main shaft accelerates rapidly, a delay may occur in the drive motor and a short pick may occur. Furthermore, even during steady operation, when performing multicolor weft insertion, the drive motor may be operated intermittently according to a predetermined weft insertion selection signal, but even in this case, there may be a delay in the response of the drive motor. If there is, there is a risk of short picks occurring.

SUMMARY OF THE INVENTION In view of the problems of the prior art, an object of the present invention is to provide a state determination section and a correction control section, and to provide a synchronous control section and a drive motor for controlling a drive motor according to a state signal from the state determination section. To provide a drive motor control device for a drum-type length measurement storage device for a loom, which can effectively compensate for a response delay of a drive motor and prevent the occurrence of short picks by applying feedforward control to a control unit. There is a particular thing.

[0008]

[Means for Solving the Problems] The structure of the present invention to achieve the above object is to compare the amount of rotation of the main shaft and the amount of rotation of the drive motor, and to make the drive motor follow the main shaft at a predetermined ratio. A synchronous control section that calculates the rotation amount deviation, a drive control section that controls the rotation of the drive motor based on the rotation amount deviation from the synchronous control section, a state determination section that determines the operating state of the loom, and a state determination section that determines the operating state of the loom. The gist thereof is to include a correction control section that applies feedforward control to at least one of the synchronization control section and the drive control section in response to a signal.

The synchronization control section includes a frequency divider that determines the ratio between the amount of rotation of the main shaft and the amount of rotation of the drive motor, and the correction control section causes the frequency divider to have different divisions depending on the status signal. The frequency ratio can be set and output.

Further, the drive control section includes a speed control system and a current control system, and the correction control section sets different correction amounts for at least one of the speed control system and the current control system depending on the state signal. It may also be output.

[0011]

[Operation] With this configuration, the synchronous control section calculates the rotation amount deviation, and the drive control section rotationally controls the drive motor based on the rotation amount deviation, so that the drive motor is determined by the synchronous control section. The drum or rotating yarn guide can be rotated following the main shaft and in synchronization with the main shaft at a predetermined ratio.

On the other hand, the correction control section applies feedforward control to at least one of the synchronization control section and the drive control section in accordance with the status signal from the status determination section, so that the drive motor is activated when the loom is started, etc. In this case, it is possible to temporarily follow the main shaft at a larger rate than during steady operation, and therefore, it is possible to effectively compensate for the response delay of the drive motor.

When the synchronization control section includes a frequency divider, the ratio between the amount of rotation of the main shaft and the amount of rotation of the drive motor is determined by the frequency division ratio set in this frequency divider. The purpose can be easily achieved by setting and outputting different frequency division ratios to the frequency divider according to the status signal.

Similarly, when the drive control section includes a speed control system and a current control system, feedforward control may be achieved by setting different correction amounts for at least one of these depending on the state signal. .

[0015]

[Embodiment] An embodiment will be explained below with reference to the drawings.

A drive motor control device for a drum-type length measurement and storage device for a loom includes a synchronization control section 10, a drive control section 20, a state determination section 30, and a correction control section 40 (FIG. 1).

The drum-type length measurement and storage device (hereinafter simply referred to as length measurement device) D is a stationary drum type, and the drum D1
, rotating yarn guide D2, and rotating yarn guide D2
, an encoder EN2 directly connected to the drive motor M, and a locking pin D3 that moves forward and backward relative to the drum D1. Yarn feeder W1
The yarn W unwound from the drum D1 can be wound around the drum D1 and stored by being passed through the drive motor M in the axial direction and pulled out from the tip of the rotating yarn guide D2. By retracting the locking pin D3 from the surface of the drum D1, the yarn W on the drum D1 can be inserted as a weft into a warp opening (not shown) through the weft insertion nozzle N.

An encoder EN1 that detects the rotation amount Pa of the main shaft A and outputs it as a pulse train signal Sa is connected to the main shaft A of the loom driven by a main motor (not shown), and the output of the encoder EN1 is controlled by synchronous control. It is branch-connected to the section 10 and the state determining section 30. The rotation amount Pf of the drive motor M from the encoder EN2 is also input to the synchronous control unit 10 as a pulse train signal Sf, and the output of the synchronous control unit 10 is input to the drive control unit 2.
0 to the drive motor M. The output of the state determination section 30 is input to the correction control section 40 as a state signal S1, and the output of the correction control section 40 is input to the synchronization control section 10,
They are individually connected to the drive control section 20.

The synchronization control section 10 consists of a frequency divider 11 and a deviation counter 12 connected in series (FIG. 2). In the frequency divider 11,
The rotation amount Pa of the main shaft A is input, and the rotation amount Pf of the drive motor M is also input to the deviation counter 12.

The drive control section 20 includes a summing point 21, a control amplifier 22, a summing point 23, and a control amplifier 24 connected in series. A current detector CT is interposed between the control amplifier 24 and the drive motor M, and the output of the current detector CT is fed back to the summing point 23.

The status signal S1 from the status determining section 30 is as follows:
The signal is branched into a selector 41 and connectors 42 and 43 of the correction control section 40 . The selector 41 includes a ratio setter 41a,
41b is attached, and the output of the selector 41 is connected to the frequency divider 11. Furthermore, the connectors 42 and 43 are provided with setting devices 42a and 43a, respectively.
The outputs of 3 are connected to summing terminals of summing points 21 and 23, respectively.

The state determining unit 30 determines the amount of rotation Pa of the main shaft A.
The DA converter 31 which inputs
3), the comparator 32 is provided with a setting device 32a. D
The A converter 31 can convert the pulse train signal Sa from the encoder EN1 into DA and output the rotational speed va of the main shaft A. The comparator 32 compares the rotational speed va from the DA converter 31 and the set speed vao set in the setter 32a, and outputs a status signal S1 when, for example, va<vao. Therefore, the status signal S1
can be used as a signal indicating a transient state after the loom is started until it reaches steady rotation.

On the other hand, the selector 41 of the correction control unit 40 selects the ratio setters 41a and 41b depending on the presence or absence of the status signal S1.
is selectively connected to the frequency divider 11, and the connectors 42 and 43 connect the setters 42a and 4 only when the status signal S1 is present.
3a is connected to the summing points 21 and 23. Therefore, when the loom is in steady operation, the status signal S1
is not present, the selector 41 can select the ratio setter 41a and send the frequency division ratio k1 set in the ratio setter 41a to the frequency divider 11.

The frequency divider 11 uses the frequency division ratio k1 given via the selector 41 to calculate Pa/k1 for the rotation amount Pa of the main shaft A, and sends it to the addition terminal U of the deviation counter 12. do. Since the rotation amount Pf of the drive motor M, that is, the drum D1, is input to the subtraction terminal D of the deviation counter 12, the deviation counter 12 calculates the rotation amount deviation ΔP=Pa/k1−Pf, and the drive control section calculates the rotation amount deviation ΔP=Pa/k1−Pf. 20
can be sent to.

The summing point 21 and the control amplifier 22 of the drive control section 20 form a speed control system for the drive motor M, and the summing point 23 and the control amplifier 24 form a current control system. The control unit 20 can control the rotation of the drive motor M so as to eliminate the rotation amount deviation ΔP. That is, the drive motor M at this time has a frequency division ratio k1
The rotation is controlled so as to follow the main shaft A at a predetermined ratio Pf /Pa = 1/k1 determined by , and the rotation amount deviation ΔP is set to realize this.

Note that the frequency division ratio k1 during steady operation can be determined as follows. In other words, now,
The pulse train signal Sa from the encoder EN1 consists of na pulses per rotation of the main shaft A, and the pulse train signal Sf from the encoder EN2 consists of the drive motor M,
That is, it is assumed that each rotation of the drum D1 consists of nf pulses. Therefore, if the drum D1 should rotate Nf times when the main shaft A rotates once, the frequency division ratio k1 can be determined as na /k1 = nf ・Nf k1 = na / (nf ・Nf ). .

In the transient state from when the loom is started until steady rotation is reached, the state signal S1 from the state determining section 30 is present, so the selector 41 selects the ratio setting device 41.
b is selectively connected to the frequency divider 11, and the ratio setter 41b sends the frequency division ratio k2 set there to the frequency divider 11. Therefore, the frequency division ratio k2 is na /k2 = nf (Nf + ΔNf) k2 =
na / (nf (Nf + ΔNf )) < k1 However, if ΔNf is determined as a positive constant, then the rotation amount deviation Δ
P=Pa/k2-Pf is the ratio Pf/Pa=1/k2 determined by the frequency division ratio k2.
It is intended to follow. That is, the drive motor M at this time can be rotated at a higher speed corresponding to the constant ΔNf than during steady operation, and can follow the main shaft A well even if the main shaft A is suddenly accelerated.

On the other hand, due to the presence of the status signal S1, the connectors 42 and 43 are connected to the setting devices 42a and 4, respectively.
3a is connected to the summing points 21, 23, the correction amounts Fv, Fi set in the setters 42a, 43a can be added to the summing points 21, 23. Correction amount Fv
, Fi act as feedforward correction amounts for the speed control system and current control system for the drive motor M, respectively, so that the responsiveness of the drive motor M can be improved by these factors as well. That is, the correction control section 40 at this time applies feedforward control to the synchronization control section 10 and the drive control section 20 by outputting the frequency division ratio k2 < k1 and outputting the correction amounts Fv and Fi. It becomes.

[0029]

[Other Embodiments] The state determining section 30 can also be configured by a counter 33 and a setting device 33a (FIG. 4). The counter 33 is reset by the starting signal Ss of the loom, and by inputting the rotation amount Pa of the main shaft A, the counter 33 is set to the setting rotation amount Pao set in the setting device 33a.
<Pao outputs status signal S1. Therefore,
The state signal S1 can indicate a transient state immediately after the loom is started. Note that the rotation amount Pa at this time may be the number of picks of the loom.

The state determining section 30 also has a timer for inputting the loom starting signal Ss and measuring the elapsed time from the starting point of the loom, and when this elapsed time is within a predetermined starting time, the state signal is output. S1 may also be output.

In these embodiments, the loom starting signal Ss can be replaced with a weft insertion selection signal from a weft insertion selection control device when performing multicolor weft insertion.

The weft insertion selection control device is, for example, an electronic dobby device, and selects a specific weft yarn in a specific loom cycle to insert the weft. It is necessary to start, stop, or change gears. Therefore, if the weft insertion selection control device sends a weft insertion selection signal to the state determination section 30 when the drive motor M should start or accelerate, the state determination section 30 will determine whether the main shaft A Rotation amount Pa
is within a predetermined set rotation amount Pao, or when the elapsed time is within the set time of the timer, the status signal S1
Therefore, the drive motor M can compensate for its response delay and quickly reach steady rotation.

Furthermore, the state determining section 30 may calculate the acceleration of the main shaft A by differentiating the rotational speed va of the main shaft A, and output the state signal S1 when this acceleration is equal to or higher than a predetermined value. In addition to the state in which the loom is accelerating after starting, the status signal S1 is
can be output, and the response of the drive motor M can be improved.

In the above explanation, the ratio setter 41a,
Frequency division ratios k1 and k2 to be set in 41b, setter 42a,
The correction amounts Fv and Fi set in 43a are, respectively,
Instead of a fixed set value, for example, the rotation speed va of the main shaft A
It may be a function of Even when the loom is operated at variable speeds at different rotational speeds, the frequency division ratios k1, k2, etc. can always be set to optimal values. Also, the frequency division ratio k1
, k2, etc., may each store the optimum value in the trial weaving process or in the past operating condition, and may be capable of so-called learning control so as to reflect it in the future operating condition. For example, each time the loom is in a transient state, the state of convergence of the rotation amount deviation ΔP is grasped and evaluated, and the results are calculated using the frequency division ratios k1, k
2, etc. should be reflected.

Note that the correction control section 40
Instead of applying feedforward control to all of the speed control system and current control system of the drive control section 20, feedforward control may be applied to only a part of them, if necessary. That is, the correction control section 40 can apply feedforward control to at least one of the synchronization control section 10 and the drive control section 20, and when targeting the drive control section 20, the correction control section 40 can perform feedforward control on at least one of the synchronization control section 10 and the drive control section 20. Feedforward control can be applied to at least one of the control system.

Further, the present invention can be applied as is to not only a stationary drum type length measuring device but also a rotating drum type length measuring device.

[0037]

[Effects of the Invention] As explained above, according to the present invention, a state determination section and a correction control section are provided for a drive motor control system consisting of a synchronous control section and a drive control section. By applying feedforward control to at least one side of the drive control section, the drive motor can effectively compensate for response delays even in transient conditions of the loom, and can follow the main shaft without delay. This has the excellent effect of effectively preventing the occurrence of short picks.

[Brief explanation of drawings]

[Figure 1] Schematic block system diagram

[Figure 2] Overall block system diagram

[Figure 3] Main block diagram

[Figure 4] A diagram equivalent to Figure 3 showing another embodiment

[Explanation of symbols]

A...Main shaft M...Drive motor Pa, Pf...rotation amount ΔP…Rotation amount deviation k1, k2...dividing ratio Fv, Fi...correction amount S1...Status signal 10...Synchronization control section 11... Frequency divider 20... Drive control section 30...Status determination unit 40...Correction control section

Claims (3)

[Claims] 1. A synchronous control unit that compares the rotation amount of the main shaft and the rotation amount of the drive motor and calculates a rotation amount deviation for causing the drive motor to follow the main shaft at a predetermined ratio; a drive control section that controls the rotation of the drive motor based on the rotation amount deviation; a state determination section that determines the operating state of the loom; and at least one of the synchronous control section and the drive control section according to the state signal from the state determination section. A drive motor control device for a drum-type length measurement and storage device for a loom, comprising a correction control section that performs feedforward control on one side. 2. The synchronization control section includes a frequency divider that determines a ratio between the rotation amount of the main shaft and the rotation amount of the drive motor, and the correction control section controls the frequency divider according to a state signal. Claim 1 characterized in that different frequency division ratios are set and outputted.
A drive motor control device for a drum-type length measurement and storage device of the described loom. 3. The drive control section includes a speed control system and a current control system, and the correction control section performs different corrections on at least one of the speed control system and the current control system depending on a state signal. 3. The drive motor control device for a drum-type length measurement and storage device for a loom according to claim 1 or 2, wherein the drive motor control device outputs a set amount.