JP2000303329A - Method for controlling length of knitted fabric with flat knitting machine and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately control the length of a knitted fabric in a knitting process, while maintaining the quality of the knitted fabric and the stability of the knitting. SOLUTION: This method for controlling the length of a knitted fabric 10 in a flat knitting machine 2 comprises imparting a prescribed tension to the knitted fabric 10, simultaneously positively pulling down the knitted fabric 10 to move the knitted fabric 10, detecting the moved distance S of the knitted fabric 10 in a prescribed course, comparing the detected moved distance S with the target value S0 of the moved distance of the knitted fabric 10 in the prescribed course to determine a deviation E, and changing at least one of DOMOKU (the density of the knitted fabric) Q, the tension T of a fed yarn and a knitting velocity V to eliminate the deviation E in the subsequent knitting processes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for controlling the length of a knitted fabric, that is, the length of the knitted fabric during knitting by a flat knitting machine.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 62-62977 compares a measured length of a yarn used for knitting a predetermined number of loops in a knitting process with a designated value based on a total extension of a predetermined number of basic loops. It discloses that the deviation is obtained, and the frequency at the time of knitting is changed in a direction to eliminate the deviation.

Further, Japanese Patent Publication No. 1-49816 discloses a knitting process in which a measured length of a yarn used for knitting a predetermined number of loops is compared with a designated value based on the total length of a predetermined number of basic loops. It discloses that the deviation is determined and the yarn feeding tension for the yarn is changed in a direction to eliminate the deviation.

[0004] Both of the above techniques presuppose that the length of the yarn is measured during the yarn feeding process. For this reason, the above-mentioned conventional technology cannot be used at the time of knitting by replacing yarns such as yarns that are difficult to measure and intarsia,
The installation of a length measuring device complicates the yarn feeding system, resulting in poor operability, high yarn feeding tension, inducing yarn breakage, difficulty in stable knitting, control delay due to yarn elongation, and errors. And it is difficult to knit a knitted fabric having a good texture. Therefore, there is a demand for a simple and practical device for preventing disturbance in the length of a knitted fabric.

[0005]

OBJECTS OF THE INVENTION It is therefore an object of the present invention to be able to accurately control the length of a knitted fabric during the knitting process while maintaining the quality of the knitted fabric and the stability of the knitting.

[0006]

According to the present invention, in a method for controlling a knitted fabric length of a flat knitting machine, the knitted fabric is actively pulled down and moved while applying a predetermined tension to the knitted fabric. In addition, the amount of movement of the knitted fabric between predetermined courses is detected, the detected movement amount is compared with the target value of the amount of movement of the knitted fabric between predetermined courses, and the detected movement amount and the target value of the movement amount are compared. At the time of occurrence of a deviation, or at the time of occurrence of a deviation exceeding the allowable deviation, by changing at least one of the stitch, the yarn feeding tension and the knitting speed, the deviation exceeding the above-mentioned allowable deviation in the subsequent knitting process. I try to eliminate.

Further, based on the above-described method for controlling the knitted fabric length of a flat knitting machine, the present invention provides a knitted fabric length control device for a flat knitting machine having a set-up plate descended by an actuator, and at least via the set-up plate. A pull-down force control device that applies a predetermined tension to the knitted fabric, a movement amount detector that detects a movement amount of the set-up plate between predetermined courses, and a movement amount detected by the movement amount detector and a predetermined course distance. By comparing with the target value of the movement amount of the set-up plate in the above, a deviation is obtained, and when a deviation occurs, or when a deviation larger than the allowable deviation occurs, in the direction of eliminating the deviation,
And a knitting control device for changing at least one of the yarn feeding tension and the knitting speed.

Here, the pull-down force control device is mainly constituted by a set-up plate only when knitting a narrow knitted fabric,
If necessary, in addition to the set-up plate, one or two or more pairs of pull-down rollers are used. The stitch change is, in detail, a change in the amount of knitting of the knitting needles. According to the needle-independent drive type (carriage-less type) flat knitting machine, the change is performed by the needle driving motor. According to the knitting machine, the adjustment is performed by adjusting the position of the cam in the carriage.

Further, the yarn feeding tension is adjusted by adjusting the resistance to the yarn at the time of yarn feeding with a yarn feeding tensor and controlling the tension (tension) of the yarn. According to the carriageless flat knitting machine, the knitting speed is changed by changing the yarn feeding speed of the yarn feeder and the reciprocating needle speed of each knitting needle. This is performed by changing the moving speed of the carriage having the yarn feeder.

[0010] During the knitting operation, the pull-down force control device lowers the set-up plate so as to bring the knitted fabric to a set target tension, or lowers the set-up plate as necessary. Alternatively, two or more pairs of pull-down rollers are driven. During this knitting process, the movement amount detector detects the movement amount of the set-up plate between predetermined courses, that is, the length of the knitted fabric. The knitting control device is
The amount of movement of the set-up plate detected by the movement amount detector,
A deviation is obtained by comparing the target value with the target value of the movement amount between a predetermined number of courses. The knitting control device includes
At least one of the knitting speeds is changed in the direction of eliminating the deviation. If the deviation is within the allowable deviation, the knitting control device does not change elements such as the stitch, the yarn feeding tension, or the knitting speed. Only when the deviation exceeds the allowable deviation, at least one of the elements Is changed so that the deviation is within the allowable deviation, more stable control can be performed.

More specifically, when the currently occurring deviation is equal to or larger than the allowable deviation and the detected movement amount> the target value of the movement amount, the control is performed for the first time, the yarn feeding tension is increased, and the knitting speed is controlled. On the other hand, when the currently occurring deviation is equal to or larger than the allowable deviation and the detected movement amount is smaller than the target value of the movement amount, the control proceeds to the second increase, the yarn supply tension decreases, and the knitting speed decreases. Decrease.

Since the length of the knitted fabric is controlled without using a length measuring device, the quality of the knitted fabric can be prevented irrespective of the knitting structure such as the yarn type and intarsia, and the stable knitting can be maintained. In addition, the length of the knitted fabric can be accurately regulated.

[0013]

FIG. 1 shows the main mechanical parts of a flat knitting machine 2 controlled by the method for controlling the knitted fabric length of the flat knitting machine of the present invention. In this example, the flat knitting machine 2 is, for example, a needle independent drive type (carriageless type) flat knitting machine. The yarn 3 for knitting is pulled out from the yarn package 3a, passes through the tensor 4, and is reciprocated by the yarn feeder 5 driven by the yarn feeding motor 9, whereby a large number of approximately 500 yarns are held by the pair of front and rear beds 6, respectively. Is supplied to the knitting needles of the knitting area.

The knitting needle 7 in the knitting area is driven by a dedicated needle motor 8 for each needle in synchronism with the reciprocating movement of the yarn feeder 5, and performs a knitting motion by reciprocating forward / backward movement based on a predetermined needle movement pattern Z. By knitting the yarn 3 on the yarn loop, that is, the knitting, the knitted fabric 10 having a predetermined knitting structure is knitted. Note that the predetermined needle movement pattern Z will be described later with reference to FIG.
It will be explained together.

The knitted fabric 10 extends downward from between the pair of beds 6, and the target pulling force F is set by the set-up plate 11.
It has been reduced by 0 and, if necessary, 1
Alternatively, it can be pulled down by two or more pairs of rollers 12 and 13 for pulling down. Therefore, the total of the pulling-down force F1 by the set-up plate 11 on the knitted fabric 10 and the pulling-down forces F2 and F3 by the pair of pulling-down rollers 12, 13 attached as necessary is reduced to the target pulling-down force F0 as a whole. Is set.

One of the pair of rollers 12 and 13 is driven on the driving side by motors 14 and 15 with torques corresponding to the pulling-down forces F2 and F3, respectively. The L-shaped levers 16 and 17 supported by fixed-point fulcrum shafts 18 and 19, respectively,
0, 21, the roller 12 on one drive side in a fixed position,
13 are provided so as to be able to freely contact and separate.

The driven rollers 12 and 13 are operated by operating devices 20 and 21, and the driven rollers 12 and 13 are driven.
13, the pair of rollers 12 and 13
The lowering force F2, F3 is not applied to the knitted fabric 10, and the set up plate 11 is allowed to rise from between them.
In the initial stage of setting up, the pair of rollers 12, 13
Being set apart, the set-up plate 11 can enter between the pair of rollers 12, 13 so that it can be locked to the lower end of the still-short knitted fabric 10 at the beginning of set-up by a pull-down needle 25. Has become. When the knitting of the abandoned knitting is completed, knitting of the main knitting of the knitted fabric 10 is started.

FIGS. 1 and 2 show an example of a device 22 for lowering the set-up plate 11. The setup plate 11
The left and right attachments 23 are connected to a pair of left and right winding bodies 24 such as an endless chain or a timing belt. When setting up, set up board 1
The yarn feeding to the knitting needle 7 is started with 1 as the highest position. Thereafter, the yarn feeding to the knitting needles 7 is repeated while gradually lowering the set-up board 11, thereby knitting the discarded knitting portion 10a of the knitted fabric 10. The setting plate 11 pulls down the discarded knitting portion 10a in a state where the pulling down needle 25 is hooked on the lower end portion of the discarded knitting portion 10a. The lowering force F1 at this time is the target lowering force F0. The pair of left and right wrapping bodies 24 are respectively wrapped around upper and lower left and right wheels 26, and are driven by a torque corresponding to the pulling-down force F <b> 1 by an actuator 28 such as a torque motor connected to a lower common shaft 27. It is designed to be driven. After the knitting of the main knitting is started, when the set-up plate 11 moves and passes between the pair of rollers 12, the pair of rollers 12 closes to sandwich the knitted fabric 10. Further, when the set up plate 11 passes between the pair of rollers 13, the pair of rollers 13 is closed and the knitted fabric 10 is closed.
In between.

In FIG. 2, the main knitting portion 10 of the knitted fabric 10 is shown.
b. 1,..., No. p is the course number. Represents In this example, as an example, knitting is performed with a stitch length a per course.

The rotation amount of the actuator 28 is detected by a movement amount detector 29 such as a pulse generator. Therefore, the movement amount detector 29 detects the movement amount S of the set-up plate 11 from the rotation amount of the actuator 28, and indirectly detects the knitted fabric length L of the knitted fabric 10 from the movement amount S.

FIG. 3 shows the construction of the knitted fabric length control device 1 of the present invention. The knitting data A such as the target pulling-down force F0 and the needle movement pattern Z based on the predetermined knitting structure and the knitting shape and the needle movement amount at the time of driving the needle and the needle speed are previously created by the knitting data setting device 30. And the pull-down force control device 31 and the knitting control device 3
It is sent to 2.

The pull-down force control device 31 outputs the knitting data A
Based on the target reduction force F0, the reduction force F1
Is generated, and the actuator controller 33,
By driving the actuator 28 by the driver 39, the pull-down force F1 is applied to the knitted fabric 10 via the set-up plate 11, and a signal corresponding to the pull-down force F2, F3 is generated. By driving the motors 14 and 15 with a predetermined torque via 40 and 41, the pull-down forces F2 and F3 are applied to the knitted fabric 10. The pulling-down force F1 or the total force of the pulling-down force F1 and the pulling-down forces F2 and F3 is equal to the target pulling-down force F0 and is a predetermined tension on the knitted fabric 10. The drivers 39, 40, 41
Generates a target torque by current feedback control.

Further, the knitting control device 32 stores the knitting data A
A drive command B signal is generated on the basis of the control signal, the yarn feed motor control section 37 and the driver 43 are driven to give a yarn feed motion to the yarn feeder 5 by the yarn feed motor 9 and the knitting data A
A drive command D signal is generated on the basis of this, the needle motor control unit 36 and the driver 42 are driven, the knitting needle 7 is driven by the needle motor 8, and the knitting needle 7 is given a knitting motion synchronized with the yarn feeding motion. Further, a signal of the drive command C is generated based on the knitting data A, and the tensor motor controller 38 and the driver 44 are driven to drive the tensor motor 45, thereby adjusting the resistance of the tensor 4 to the yarn 3.

The knitting control device 32 compares the movement amount S of the set-up plate 11 between the predetermined courses detected by the movement amount detector 29 with the target value S0 of the movement amount between the predetermined courses, Find the deviation E. When the deviation E, to be precise, the absolute value of the deviation E is equal to or larger than the allowable deviation e, the knitting control device 32 generates a signal corresponding to the deviation E and sends the signal to the needle motor control unit 36. The needle motor control unit 36 changes the data of the stitch Q, that is, the data of the stitch pull-in amount q of the knitting needle 7 in the drive command D based on the knitting data A in the deviation eliminating direction.

Further, the knitting control device 32 determines the data of the knitting speed V, that is, the needle speed v1 of the reciprocating motion of the knitting needle 7, the yarn feeding speed v2 of the yarn feeder 5, and the like among the drive commands B and D according to the deviation E. Then, the data of the yarn feeding tension T by the tensioner 4 is changed in the deviation eliminating direction. As described above, the change target is the stitch Q, the yarn feeding tension T, and the knitting speed V (the yarn feeding speed v2 of the yarn feeder 5 and the needle speed v1 of the reciprocating motion of the knitting needle 7).
And at least one of them is combined at a predetermined ratio as necessary.

FIG. 4 shows a specific configuration of the pull-down force control device 31. Based on the knitting data A from the knitting data setting device 30, the arithmetic unit 46 inside the pull-down force control device 31 determines the number of loops in one course, the stitch length a,
b or a correction parameter for the consumed yarn length, and the input side is connected to the pull-down force setting device 47, the distribution ratio setting device 48, and the increase / decrease ratio setting device 49, and the output side is connected to the pull-down force F1. , F2, F3, the actuator control unit 33, the motor control units 34,
Send to 5.

The pull-down force setting unit 47 stores a target pull-down force f per unit loop, for example, one loop, according to the structure of the knitted fabric 10, and this target pull-down force f
Is always sent to the arithmetic unit 46. Note that the target reduction force f may be a value per a plurality of loops. Further, the distribution ratio setting device 48 includes a pull-down force F1 acting on the set-up plate 11, a pull-down force F2 acting on the upper pair of rollers 12, and a pull-down force F2 acting on the lower pair of rollers 13.
Are provided for setting the distribution ratios K1, K2, and K3. For example, the pull-down force F1 is set to about 2/3 of the target pull-down force F0, and the pull-down forces F2 and F3 are each set to about 1/6 of the target pull-down force F0. At this time, the distribution ratios K1, K2, and K3 are 2/3, 1
/ 6, 1/6.

The increase / decrease ratio setting unit 49 is provided to correct the content of the calculation based on the increase / decrease ratio J based on the correction parameter of the knitting data A. When knitting a knitted fabric in which the stitch length a is changed even if the number of loops is the same in the specific course during knitting, the stitch length is adjusted in order to realize the optimal pulling-down force for the changed stitch length a. The calculation content is corrected based on the correction parameter a. For example, in a course where the stitch length a is largely changed, the calculation content is corrected so that the pulling-down force is increased. Note that the stitch length a refers to the length of a thread forming one loop, but a signal related to the stitch length a is sufficient as a correction parameter. Instead of the signal of the stitch length a, for example, a signal of a loop length may be used. Further, since the size of the stitch length a ultimately corresponds to the size of the consumed yarn length of each course, it may be replaced with, for example, the consumed yarn length per course.

For this purpose, the increase / decrease ratio setting unit 49 sends a preset increase / decrease ratio J to the arithmetic unit 46 within a correctable range value. It should be noted that the increase / decrease ratio J is set to 0. 0 in accordance with the correction range value of the correction parameter and the correction parameter.
8, 1.0, 1.2, etc.

The computing unit 46 obtains the target pulling force F0 from the target pulling force f per unit loop and the number of loops per course of the knitted fabric 10, and obtains the target pulling force F0.
By performing distribution calculations based on the distribution ratios K1, K2, and K3, signals of the pull-down forces F1, F2, and F3 are generated, and these signals are respectively transmitted to the actuator control unit 3.
3. It is sent to the motor control units 34 and 35. As described above, the actuator control unit 33 and the motor control unit 3
4 and 35 and the drivers 39, 40 and 41 adjust the torques of the corresponding actuators 28 and motors 14 and 15 according to the output values of the pulling-down forces F1, F2 and F3, respectively, and apply the necessary force to the set-up plate 11. By applying the necessary rotational force to the pair of rollers 12 and 13, an appropriate target pulling force F0 is applied to the knitted fabric 10 in the vicinity of the tooth gap of the bed 6.

By controlling the lowering force, a knitting needle 7 in the knitting area is used for knitting the tack during the knitting process.
Are formed, and even if the number of loops changes in each course, or in order to reduce the number of eyes, the number of active knitting needles 7 decreases in each course, and a plurality of loops are formed for a small number of knitting needles 7. Even if it does, since an appropriate pulling-down force is applied to the knitted fabric 10 in accordance with the number of loops in one course, there is no decrease in the tension on the knitted fabric 10 in the course, and uneven loop formation and knitting errors occur. Can be prevented beforehand.

FIG. 5 shows a configuration example of the knitting control device 32. Based on the knitting data A from the knitting data setting device 30, the knitting control circuit 50 sends a signal of a drive command B necessary for the movement of the yarn feeder 5 to the yarn feeding motor control unit 37 and a tensor motor control unit 38, as described above. , A signal of a drive command C corresponding to the target yarn feeding tension T is generated, and a signal of a drive command D according to the needle movement pattern Z is sent to the needle motor control unit 36.

Further, the knitting control circuit 50 outputs a signal of the calculation command G to the target value calculating circuit 51 every predetermined course, and resets the counter 52 at the start of the main knitting so as to reset the counter 52. Occurs. The target value calculation circuit 51 calculates a target value S0 of the movement amount of the set-up board 11 for each predetermined course, and outputs the target value S0 to the comparison operation circuit 53. The counter 52 is connected to the movement amount detector 29, detects the movement amount S of the set-up plate 11 as a count value from the rotation amount of the actuator 28, and outputs the detected movement amount S to the comparison operation circuit 53. ing.

Therefore, the comparison operation circuit 53 compares the detected movement amount S of the set-up plate 11 between the predetermined courses with the target value S0 of the movement amount between the courses, and obtains the deviation E. When the calculated absolute value of the deviation E is equal to or larger than the allowable deviation e, the comparison operation circuit 53 generates an output corresponding to the absolute value of the deviation E and the sign of the positive or negative. I do.

In the knitting process, the deviation E between the predetermined courses in the predetermined knitting section or the deviation between the predetermined courses in all the knitting sections for each of the specific stitch lengths a and b during the knitting process. The average value of E and the like are stored, and the automatic knitting operation after the trial knitting or the lowering limit S of the set-up plate 11
In the case of knitting a knitted fabric 10 longer than lim, preparation is made for use as deviation data after the set-up plate 11 has reached the lower limit (limit value). Incidentally, the composition control circuit 50, the target value calculation circuit 51, the counter 52, the comparison operation circuit 53, the storage circuit 54, and the like may be configured as one or more CPUs.

FIG. 6 shows a control system for a large number of knitting needles 7 of about 500. The position command circuit 55 of the needle motor control unit 36 receives the signal of the drive command D according to the needle movement pattern Z from the knitting control circuit 50, and generates a signal of the needle speed v1 and the needle target position H for each knitting needle 7. The signals of the needle speed v1 and the needle target position H are stored in the storage circuit 56 together with the needle number and the like, and then sent to the servo control circuit 57 of the driver 42 for each knitting needle 7 as a pulse signal of the needle target position H and the drive circuit. 58 is given as a command signal of the needle speed v1.

The servo control circuit 57 drives the drive circuit 58 in response to the pulse signal of the needle target position H, thereby controlling the needle motor 8 such as a linear motor to a predetermined needle speed v.
1, the reciprocating motion is given to the corresponding knitting needle 7, the displacement of the needle motor 8 is detected by the encoder 59, and the detected position signal pulse is used as a feedback signal under feedback control. Drive. The portion of the needle target position H corresponding to the stitch pull-in amount q is changed by the deviation E, as described later.

FIG. 7 shows an example of the needle movement pattern Z. In this figure, the horizontal axis indicates time or the amount of movement of the yarn feeder 5, and the vertical axis indicates the needle target position H of the knitting needle 7, respectively. When the yarn feeder 5 being moved is at the position shown in the figure, the leading end positions of a large number of the knitting needles 7 before and after the traveling direction of the yarn feeder 5 have a continuous solid curve. Focusing on one knitting needle 7, the knitting needle 7 waiting at the position of the tooth of the bed 6 rises upward (positive direction), and then retracts by a predetermined distance toward the tooth to lock the thread 3. do it,
At this position, it stops for a predetermined period of time, then retreats downward (in the minus direction) by a certain stitch pulling-in amount q from the position of the tooth gap, and returns to the position of the tooth gap with the thread 3 locked.

Here, the stitch pull-in amount q of the knitting needle 7
Corresponds to the score Q. Therefore, the change of the time Q
This corresponds to changing a part of the needle target position H according to the deviation E and changing the stitch drawing amount q of the needle movement pattern Z in the deviation eliminating direction.

FIG. 8 shows a control system for the yarn feeder 5. The yarn feed motor control unit 37 sends a signal of the target position I to a servo control circuit 60 inside the driver 43 of the yarn feeder 5 for a position command, and sends a yarn feed speed v2 to a drive circuit 61 to supply the yarn. The motor 9 is driven. The yarn feed motor 9 gives the yarn feeder 5 a reciprocating motion in the needle row direction, thereby
Is guided to the knitting needle 7 at the knitting position, and the yarn 3 is engaged with a large number of knitting needles 7. The yarn feed speed v2 of the yarn feeder 5
Is set in advance, but is adjusted by the signal of the drive command B when the knitting speed V is changed.

FIG. 9 shows a control example of the tensor 4.
The tensor motor control unit 38 and the driver 44 in FIG.
By inputting the signal of the drive command C from the knitting control device 32,
Driving the tensor motor 45 in the deviation eliminating direction,
2, the tension T is adjusted by pressing one of the tensers 4 against the other of the tensers 4 to give a predetermined pull-out resistance to the yarn 3 between the pair of tensers 4. The other tensor 4 is urged by a spring 63 against a fixed portion.

FIG. 10 shows, as an example, the movement amount S of the set-up board 11 from the start of the main knitting to the present time at the end of each course in the course of the control operation, and the same as the detected movement amount S. A comparison is made between the target value S0 of the movement amount of the set-up plate 11 between the courses, and when a deviation E equal to or more than the allowable deviation e occurs between the detected movement amount S and the target value S0 of the movement amount of the set-up plate 11, Time Q, that is, stitch pull-in amount q
5 shows a flowchart when only the value is changed. In this flowchart, the knitting control circuit 50, the target value calculation circuit 51, the comparison operation circuit 53, and the needle motor control unit 36
Are performed as a series of control procedures. In this example, the movement amount S from the start of the main knitting to the present time is detected every time one course is completed. It corresponds between the courses. Moreover, every time the movement amount S is detected, the distance between the predetermined courses increases by one course.

The knitting control circuit 50 of the knitting control device 32
After the start of the control operation, the main knitting portion 10b of the knitted fabric 10
Immediately after the start of knitting, a reset R signal is output to the counter 52. At this time, the counter 52 starts measuring the movement amount S (the amount of reduction after the start of the main knitting) of the set-up plate 11, that is, the measurement of the knitted fabric length L, with the knitting start position of the main knitting portion 10b of the knitted fabric 10 as the origin. .

Next, the composition control circuit 50 confirms the completion of composition.
And when Y (Yes), proceed to the end,
When the control operation is completed, when N (No), a one-course signal is output to the target value calculating circuit 51 as a signal of the calculation command G every time one course is completed. Upon input of the one-course signal, the target value calculating circuit 51 uses the knitting data A to determine the current course number in the main knitting process. X is calculated, and the corresponding stitch lengths a and b per course are read from the knitting data A.

Here, the comparison operation circuit 53 includes a counter 5
The count value is taken from 2 and the movement amount S of the set-up board 11 is stored.

Next, the comparison operation circuit 53 determines that the movement amount S <
Limit value Slim of the moving amount S? Make a judgment. Movement amount S <
Limit value Slim of the moving amount S? When the determination is Y, the comparison operation circuit 53 causes the target value calculation circuit 51 to start calculating the target value S0 of the movement amount.

The target value calculation circuit 51 calculates the current course N
o. X, the stitch length a, the target pulling-down force F0, and the respective pulling-down forces F1, F2, F3, are used to determine the course No. X
The target value S0 of the movement amount at is obtained. In addition, as shown in FIG. Between 1 and m, the knitted fabric 10 is pulled down only by the set-up board 11 and the course No. between m + 1-n
The knitted fabric 10 is pulled down in cooperation with the set up plate 11 and the pair of rollers 12, After n + 1, the knitted fabric 10 is lowered together with the set-up plate 11, the pair of rollers 12, and the pair of rollers 13.

The current course No. When X satisfies 1 ≦ X ≦ m, a pulling-down force F0 (F0 = F1) acts on the knitted fabric 10 over the entire area from the knitting needles 7 to the set-up plate 11. Therefore, the target value calculation circuit 51 calculates the loop length a0 from the stitch length a, the target pulling-down force F0, and the number of wales. The determined loop length a0 is the knitted fabric 1
Since the loop length when 0 is reduced by the target reduction force F0 is shown, the target value S0 of the movement amount is obtained as X × a0.

The current course No. X is m + 1 ≦ X
When ≦ n, the pulling-down force F0 (F0 = F1 + F2) acts on the knitting fabric 10 from the knitting needle 7 to the pair of rollers 12, and the pulling-down force F1 acts on the pair of rollers 12 to the set-up plate 11. ing. Target value calculation circuit 5
In step 1, the loop length a1 is obtained from the pull-down force F1 and the number of wales in addition to the loop length a0. The obtained loop length a1 indicates the loop length when the knitted fabric 10 is pulled down by the pulling force F1. Further, the target value calculation circuit 51 obtains the number of stitches y1 in the vertical direction between the knitting needle 7 and the pair of rollers 12, and finally calculates the target value S0 of the movement amount as y1 × a.
It is obtained as 0+ (X−y1) a1.

Further, the current course No. X is n + 1 ≦
At the time of X, the pulling force F0 (F0 = F1 + F2 + F3) is applied from the knitting needle 7 to the pair of rollers 12 in the knitted fabric 10.
Is working, and a pair of rollers 1
3, the pulling-down force F1 + F3 is acting, and from the pair of rollers 13 to the set-up plate 11, the pulling-down force F1 is acting. The target value calculation circuit 51 calculates the loop length a0,
In addition to a1, the loop length a2 is determined from the pulling-down force F1 + F3 and the number of wales. The required loop length a2
Shows the loop length when the knitted fabric 10 is pulled down by the pulling-down force F1 + F3. Furthermore, the target value calculation circuit 51
In addition to the number of stitches y1, a pair of rollers 12
The number y2 in the vertical direction between 3 is obtained, and finally the target value S0 of the movement amount is calculated as y1 × a0 + y2 × a2 + (X−y
1-y2) Obtained as a1.

The comparison operation circuit 53 compares the obtained target value S0 of the moving amount with the detected moving amount S, obtains a deviation E from the target value S0 of the moving amount-the moving amount S, and calculates the absolute value of the deviation E. <In the calculation of the allowable deviation e, no deviation signal is output at the time of Y because of a good control state. Therefore, the needle motor controller 36 does not change the frequency Q. However, when the absolute value of the deviation E is smaller than the allowable deviation e in the calculation of the absolute value of the deviation E <the allowable deviation e, that is, when the absolute value of the deviation E is equal to or larger than the allowable deviation e, the comparison operation circuit 53 outputs the deviation signal to the needle motor control. Output to the unit 36. The needle motor control unit 36 determines from the input deviation E that the target value S0 of the moving amount> the moving amount S? Is determined, and the result Q is increased or decreased in the direction of eliminating the deviation E based on the results Y and N.

When the movement amount S reaches the limit value Slim at the time of knitting the knitted fabric 10 longer than the limit value Slim at the time when the set-up plate 11 reaches the lower limit, the above-mentioned movement amount S <movement amount S Limit value Slim? Is N. When N, the movement amount S due to the movement of the set-up plate 11
Becomes impossible, the comparison operation circuit 53 uses the data stored in the storage circuit 54 to calculate and change the stitch Q for the remaining knitting, proceeds to the end, and ends the control.

The above control is repeated for each course. When the knitting control circuit 50 determines that knitting has ended,
The control ends.

FIG. It is a graph which shows the knitted fabric length L with respect to. Set up board 11 in this graph
, That is, the knitted fabric length L of the knitted fabric 10 is represented by a solid line. The inclination of the solid line changes halfway, but this is due to the change in the stitch lengths a and b of the knitting structure.
During knitting, the knitted fabric length L of the knitted fabric 10 is represented by a broken line. A certain course No. When the knitted fabric length L is insufficient at i and the deviation E at that time deviates from the allowable deviation e in the negative direction, the control system increases, for example, the frequency Q to eliminate the deviation E. . As a result, the next course No. At j, the knitted fabric length L falls within the range of the allowable value e.

As in the above example, instead of setting the predetermined course between the start of the main knitting and the current course, the number of courses is set in advance, and the number of courses from the current course to the set past number of courses is set. May be a predetermined course.
For example, the number of courses = 10 is set in advance, and the movement amount S is set between the current course X and the past 10 courses.
Alternatively, the target value S0 of the movement amount may be obtained, and the step Q or the like may be changed in a direction to eliminate the deviation E between them.

Also, instead of obtaining the loop length from the stitch length a and each pulling-down force, at the time of trial knitting, the first course of the main knitting (each integer of 1 to p)
Up to this point, the movement amount S of the set-up plate 11 may be determined for each course, and these values may be set in advance in the storage unit in the knitting control circuit 50 as the target value S0 of the movement amount. At this time,
The target value calculation circuit 51 stores the current course number from the storage unit for each course. A target value S0 of the movement amount corresponding to X is selected, and this is compared with the actual movement amount S. Further, the loop lengths a0, a1, and a2 may be set in advance.

Further, the knitting control circuit 5 shown in the above example
When the control operations of the target value calculation circuit 51, the comparison calculation circuit 53, and the needle motor control unit 36 are configured by one CPU, a program according to the flowchart shown in FIG. 10 may be executed.

As described above, the object to be changed for eliminating the deviation may be only the stitch Q, only the yarn feeding tension T, or only the knitting speed V, or a combination of two or more of these. It may be performed as follows. In the case of a carriageless type flat knitting machine, the yarn feeding speed v2 and the needle speed v1 of the knitting needle 7 synchronized therewith are simultaneously changed. Further, the knitted fabric length L of the knitted fabric 10 can be measured by detecting the position of the set-up plate 11 with various position sensors.

As described above, when two or more elements of the three objects to be changed are changed in the deviation elimination direction, the distribution ratios K1, K2, and K3 to the elements with respect to the deviation E are set. If the changing element is changed with respect to the corresponding deviation, better control becomes possible.

[0060]

According to the present invention, the amount of movement of the set-up plate is detected for each predetermined course, and at least one of the stitch, the yarn feeding tension, and the knitting speed is changed in accordance with the deviation from the target value. Therefore, it is possible to knit a knitted fabric having a predetermined knitted fabric length while maintaining the quality of the knitted fabric and the stability of knitting.
Because this knitted fabric length control does not use a length measuring device,
Regardless of the knitting structure such as yarn type or intarsia,
While preventing quality deterioration of knitted fabric and maintaining stable knitting,
The length of the knitted fabric can be regulated accurately.

[Brief description of the drawings]

FIG. 1 is a side view of a mechanical part of a flat knitting machine.

FIG. 2 is a side view of the pulling-down device of the set-up plate.

FIG. 3 is a block diagram of a main part of the knitted fabric length control device.

FIG. 4 is a block diagram of a pull-down force control device.

FIG. 5 is a block diagram of a knitting control device.

FIG. 6 is a block diagram of a knitting needle control system.

FIG. 7 is a graph of a needle movement pattern of a knitting needle.

FIG. 8 is a block diagram of a yarn feeder control system.

FIG. 9 is an explanatory diagram of a control system of the tensor.

FIG. 10 is a flowchart of a control operation.

FIG. 5 is a graph of the knitted fabric length (the amount of movement of the set-up board) with respect to.

FIG. FIG. 5 is an explanatory diagram of a correspondence relationship between the progress of the roller, the operation state of the roller, and the pulling-down force.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 knitting fabric length control device 2 weft knitting machine 3 yarn 3a yarn package 4 tensor 5 yarn feeder 6 bed 7 knitting needle 8 needle motor 9 yarn feeding motor 10 knitted fabric 10a discard knitting part 10b main knitting part 11 set up plates 12, 13 rollers 14 , 15 Motor 16, 17 Lever 18, 19 Support axis 20, 21 Operating device 22 Pulling device 23 Attachment 24 Wrapping body 25 Needle for pulling down 26 Wheel 27 Axis 28 Actuator 29 Moving amount detector 30 Knitting data setting device 31 Pulling force Control device 32 Knitting control device 33 Actuator control unit 34, 35 Motor control unit 36 Needle motor control unit 37 Yarn feed motor control unit 38 Tensor motor control unit 39, 40, 41 Driver 42, 43, 44 Driver 45 Tensor motor 46 Computing unit 47 Pull down Force setting Device 48 distribution ratio setting device 49 increase / decrease ratio setting device 50 knitting control circuit 51 target value calculation circuit 52 counter 53 comparison operation circuit 54 storage circuit 55 position command circuit 56 storage circuit 57 servo control circuit 58 drive circuit 59 encoder 60 servo control circuit 61 Drive circuit 62 Feed screw 63 Spring A Knitting data B Drive command C Drive command D Drive command E Deviation F0, F1, F2, F3 Lowering force G Calculation command H Needle target position I Target position J Increase / decrease ratio K1, K2, K3 Distribution ratio L Length of knitted fabric M Number of courses N No Qth R reset S Movement amount S0 Target value of movement amount Slim Limit value T Feeding tension V Knitting speed X Current course number Y Yes Z Needle movement pattern a Stitch length a0, a1, a2 Loop length b Stitch length e Tolerance f Target reduction force i, j Course No. m, n, p Course No. q Stitch pull-in amount y1, y2 Number of stitches v1 Needle speed v2 Yarn feeding speed

Claims (4)

[Claims] In a knitting process by a flat knitting machine, a knitted fabric is actively pulled down and moved while applying a predetermined tension to the knitted fabric, and a movement amount of the knitted fabric between predetermined courses is detected and detected. The target travel distance between the detected travel distance and the target value of the travel distance is compared between the detected travel distance and the target value of the travel distance of the knitted fabric between predetermined courses.
A knitting fabric length control method for a flat knitting machine, wherein a deviation is eliminated in a subsequent knitting process by changing at least one of a stitch, a yarn feeding tension, and a knitting speed. 2. The method according to claim 1, wherein the detected movement amount is compared with a target value of the movement amount of the knitted fabric between predetermined courses, and a deviation greater than an allowable deviation is generated between the detected movement amount and the target value of the movement amount. 2. The flat knitting machine according to claim 1, wherein at least one of the stitch length, the yarn feeding tension, and the knitting speed is changed to eliminate a deviation that is equal to or more than the allowable deviation in a subsequent knitting process. Ground length control method. 3. A flat knitting machine, comprising a set-up plate lowered by an actuator, a pull-down force control device for applying a predetermined tension to a knitted fabric at least via the set-up plate, and movement of the set-up plate between predetermined courses. A moving amount detector for detecting the amount, and comparing the moving amount detected by the moving amount detector with a target value of the moving amount of the set-up plate between predetermined courses, to obtain a deviation, and a direction for eliminating the deviation. A knitting control device for changing at least one of the stitch, yarn feeding tension and knitting speed. 4. A deviation is obtained by comparing a movement amount detected by a movement amount detector with a target value of a movement amount of the set-up plate between predetermined courses, and when a deviation exceeding an allowable deviation occurs, this deviation is calculated. 4. The knitting fabric length control device for a flat knitting machine according to claim 3, further comprising a knitting control device that changes at least one of a stitch, a yarn feeding tension, and a knitting speed in a direction in which the knitting is canceled.