JPH0791733B2 - Warp delivery control method for loom - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a warp delivery control method in a loom.

(Prior Art) In the warp delivery control of a loom, the method of controlling the rotation of the warp delivery motor based on the warp tension information, the warp beam diameter information, etc. by using a warp delivery motor independent of the machine base drive motor This is effective in accurately controlling the warp tension that affects the warp. An example of a sending device for that purpose is disclosed in JP-A-59-157354, and a speed command signal obtained by superimposing the output from the proportional-plus-integral-derivative control circuit (PID) and the detected rotation speed of the machine base It is designed to be output to the motor.

(Problems to be Solved by the Invention) However, in this warp feed-out control system which is a feedback system, it is necessary to control the warp elongation which is different depending on the kind of warp, so that the proportional-integral-derivative control circuit in the conventional example is used. Since the setting of the control constant must be changed, it cannot be said that the control is appropriate in consideration of the warp elongation that affects the stability and accuracy of the warp delivery control.

Configuration of the Invention (Means for Solving Problems) Therefore, in the first invention, a compensation gain for warp elongation is incorporated into a loop transfer function in a feedback system for controlling rotation of a warp feed motor independent of a loom drive motor. The reciprocal of the difference between the warp tension detected in advance and the warp tension detected after a predetermined amount of rotation of the warp feed motor is set as the compensation gain. In the second invention, the warp beam diameter after the warp beam replacement is In consideration of the case where it is larger than the previous time, the compensation gain is multiplied by the ratio of the warp beam diameter measured immediately after starting the loom after setting the compensation gain and the preset warp beam diameter larger than the measured warp beam diameter. The set value is reset as the compensation gain.

(Operation) That is, by setting the compensation gain, the loop transfer function of the feedback system becomes a function that does not include elements related to warp elongation at a warp beam diameter that is equal to or smaller than the warp beam diameter when the compensation gain is set, and is stable. Tension control is performed. If the warp beam diameter is larger than the warp beam diameter when the compensation gain is set, the loop gain of the loop transfer function increases in proportion to the warp beam diameter increase rate, and the tension control becomes unstable. Therefore, the value obtained by multiplying the compensation gain by the ratio of the warp beam diameter measured immediately after starting the loom after setting the compensation gain and the preset warp beam diameter larger than the measured warp beam diameter is re-established as the compensation gain. By setting, the loop gain of the loop transfer function that incorporates this reset compensation gain matches the loop gain when the warp beam diameter is set, and in the case of the same type of warp, in the region below the set warp beam diameter The warp delivery control after the arbitrary warp beam replacement is performed stably. When the warp type is changed, the compensation gain may be set in the same manner as described above, and it is not necessary to go through the troublesome process of resetting the control constant as in the conventional example.

(Example) Hereinafter, one example which materialized the present invention is described based on a drawing.

Warp beam 1 is rotationally driven by a motor M2 delivery reversible warp independent of machine base driving motor M1, the warp threads T fed from the warp beam 1 is set by the tensioning device (not shown) at a tension roller 2 warp tension P ₀ Is granted. The warp guided through the tension roller 2 to the shedding system 3 is subjected to the opening and closing opening forming motion, so that the weft Y is wefted into the warp shed and is also struck by the reed 4 onto the cloth W1 of the woven cloth W. . And the woven cloth W is a machine base drive motor
It is taken up by the take-up roller 5 which is rotationally driven by M1.

The warp yarn delivery motor M2 receives rotation control based on a control command from the controller C1, and the controller C1 receives information about the warp yarn tension from the warp yarn tension detector 6 including a load cell and an encoder 12 that detects the number of revolutions of the warp yarn delivery motor M2. Program calculation based on rotation speed information and the like is performed based on a program command from the machine control computer C. The controller C1 includes a central processing unit (CPU) 11, a first arithmetic unit 7 including a proportional-derivative control circuit, a second arithmetic unit 8 including a proportional-integral control circuit, and a multiplier 9.
The first calculator 7 calculates the calculated value Pb from the calculator 8 and the addition point 10
The arithmetic unit 8 outputs the arithmetic value Pa based on the input arithmetic value Pb from the arithmetic unit 7 to the multiplier 9. The multiplier 9 calculates the calculated value Pa, the constant Kp and the weft density n input from the CPU 11.
Based on the quotient expression (Kp / n) and the coefficient N of the multiplier 9 = Kp ·
Pa / n is configured and the number of pulse signals from the encoder 16 for the machine drive motor M1 and the product of the coefficient N and the constant c are output to the addition point 10. Therefore, the output from the addition point 10 becomes the addition value of the operation value Pa and the multiplication value, and this addition value is output to the drive circuit 15 via the up / down counter 13 and the D / A converter 14.

FIG. 2 is a block diagram showing a feedback system for controlling the rotation of the warp yarn feeding motor M2. The up / down counter 13, the D / A converter 14, the warp yarn feeding motor M are shown.
The transfer function Gm (s) in the loop consisting of 2 and the encoder 12 for the warp feeding motor M2 is obtained as follows.

Gm (s) = (1 / s) K1 {K2 / (1 + sT2)} ÷ [1+ (1 / sK1 ・ {K2 / (1 + sT2) H}] ＝ K1 ・ K2 / (s ² T2 + s + K1 ・ K2 ・ H) ＝ (1 / H) ÷ {(T2 / K1 ・ K2 ・ H) s ² ＋ (1 / K1 ・ K2 ・ H) s + 1}
(1) where 1 / s is the transfer function of the up / down counter 13 and K1 is D
The transfer function of the / A converter 14, K2 / (1 + sT2) is the transfer function of the warp feeding motor M2, H is the transfer function of the encoder 12 (that is, the number of pulse signals per rotation of the encoder 12), and K2 is [rotation Number / command voltage], T2 is a time constant representing the time until the warp yarn delivery motor M2 reaches a certain ratio of the predetermined rotation speed when the command voltage for obtaining the predetermined rotation speed is applied. Transfer function Gm expressed by equation (1)
(S) is an approximate representation of the following general expression of second-order lag.

Km / (T ² s ² + 2ζTs + 1) The time constant T, damping element ζ, and gain Km in the general expression of the second-order lag are expressed as follows.

T = (T2 / K1 ・ K2 ・ H) ^1/2 ζ = (1/2) ・ 1 / (K1 ・ K2 ・ H) ・ (K1 ・ K2 ・ H / T2) ^1/2 = (1/2)・ {1 / (T2 ・ K1 ・ K2 ・ H)} ^1/2 = T / 2T2 Km = 1 / H The response time of the warp feeding motor M2 is negligible with respect to the time when the diameter D of the warp beam 1 changes. Because it is short
The following approximations are possible.

T = (T2 / K1 · K2 · H) ^1/2 ≈0 Therefore, the transfer function Gm (s) represented by the equation (1) can be approximated as follows.

Gm (s) ≈1 / H = Km (2) If the rotation speed of the loom is Nr, the transfer function G (s), the transfer function Ge of the encoder 16 (that is, the pulse signal per one rotation of the encoder 16) Number), using the transfer function Gg of the reduction gear mechanism (not shown) from the warp delivery motor M2 to the warp beam 1 and the circumferential length πD of the warp beam 1, the warp delivery speed
Vl is expressed as follows.

Vl = Nr ・ Ge ・ (Kp ・ Pa / nc) ・ Gm (s) ・ Gg ・ πD ・ ・
(3) On the other hand, the woven fabric take-up speed Vw is expressed as follows using the rotational speed Nr of the loom and the weft density n.

Vw = Nr · (1 / n) (4) The warp feed-out speed Vl and the cloth take-up speed Vw can be placed in an equivalence relation when the detected warp tension and the set tension P match. This gives the following equation:

Ge ・ (Kp ・ Pa / nc) ・ Gm (s) ・ Gg ・ πD = 1 / n ・ ・ ・
(5) Here, the constant Kp is set as follows.

Kp = c / (Ge · Km · Gg · π) (6) Equation (5) becomes as follows by substituting Equations (2) and (6).

Pa · D = 1 Therefore, D = 1 / Pa (7) 1 / s in the block diagram of FIG. 2 is the transfer function (that is, the elongation of the warp T) of the integral element of (Vl−Vw), E Is the warp elastic coefficient, Gt (s) is the transfer function of the warp tension detector 6, Gc is the transfer function of the A / D converter 17 for the warp tension detector 6, and Kx is the warp beam diameter D and the warp elastic coefficient E. Shows the compensation gain, calculates the warp elastic modulus E, calculates the compensation gain Kx, Kp / n
And the calculation of (P ₀ −P) Kx are performed by the CPU 11.
However, P ₀ is the set warp tension, and P is the detected warp tension. CP
U11 is the number of pulse signals per revolution of encoders 12 and 16 H,
Ge, set warp tension P ₀ , weft density n, set warp beam diameter
The various calculations described above are performed based on Dmax and the calculated value Pa from the calculator 8.

The tension setting of the warp yarn T after the warp beam replacement and before the machine base is started is performed as follows. The CPU 11 outputs the speed command of the warp yarn discharge motor M2 which becomes the set feed speed V ₀ to the up / down counter 13 in accordance with the command of the machine base control computer C,
As a result, the warp delivery motor M2 is rotated in the normal direction or the reverse direction in the warp tension increasing direction. When the warp tension reaches a predetermined ratio (for example, 60%) of the set warp tension P ₀ , the CPU 11 issues a stop command for the warp delivery motor M2, and then 1 of the warp delivery motor M2 for removing backlash of the warp delivery mechanism.
Command rotation operation. The CPU 11 keeps track of the detected warp tension P ₁ after the time required for the warp tension to stabilize, and then commands the warp delivery motor M 2 to make one rotation operation in the same direction. Then, the CPU 11 grasps the detected warp tension P ₂ after the time required for the warp tension to stabilize after this one revolution.

The CPU 11 calculates and sets a compensation gain Kx represented by the following equation based on the detected warp tensions P ₁ and P ₂ .

Kx = 1 / (P ₂ −P ₁ ) = 1 / ΔP (8) As a result, the warp tension control is performed, and when the detected warp tension reaches near the set warp tension P ₀ , the warp feed motor M2 is stopped. A command is issued and the loom is placed in a standby state for activation. Then, the operation of the loom is started in a state where the tension of the warp T is substantially at the set warp tension P ₀ according to the loom operation command.

The warp elastic modulus E included in the loop transfer function G (s) of the warp delivery control system shown in the block diagram of FIG. 2 uses the tension difference ΔP in the equation (8), and the unmeasured actual warp beam is used. Since the diameter is D _0, it is expressed as follows.

_{E = (P 2 -P 1)} / (πD 0 · Gg) = ΔP / (πD 0 · Gg) ··· (9) loop transfer function of the warp let-off control system including the warps elastic modulus E G (s) Is represented as follows.

G (s) = Gm (s) ・ Gg ・ πD ・ 1 / s ・ E ・ Gt (s) ・ Gc ・ Kx ・ Gx (s) = C (s) ・ Gg ・ πD ・ E ・ Kx ・ ・ ・ ( 10) However, C (s) = Gx (s) .Gm (s) .1 / s.Gt (s) .Gc Equation (10) is as follows when Equation (9) is substituted.

G (s) = C (s) · D / D ₀ · ΔP · Kx (11) Then, if the compensation gain Kx set in the equation (8) is used, the equation (11) becomes as follows. .

G (s) = C (s) .D / D ₀ ... (12) Since D ₀ is the warped beam diameter at that time, D = D ₀ , and equation (12) is as follows.

G (s) = C (s) That is, by setting the compensation gain Kx to 1 / ΔP, the open loop transfer function G (s) becomes a function that does not include the warp elastic coefficient E and the warp beam diameter. The diameter D of the warp beam 1 decreases from the initial diameter Do with the operation of the loom, and the warp beam diameter D is larger than the compensation gain Kx obtained at the initial diameter D ₀ .
The compensation gain at is higher by D ₀ / D. However, since the loop gain G (s) in the case of the warped beam diameter D is lower by D / D ₀ than in the case of the set diameter D ₀ ,
The loop gain G (s) for the warped beam diameter D matches the loop gain for the initial diameter D ₀ . Therefore, if the compensation gain Kx is set with an arbitrary warp beam 1, the loop gain decreases in proportion to the subsequent decrease in the diameter of the warp beam 1 (D ≦ D ₀ ), and stable tension control becomes possible.
Moreover, the compensation gain is set without modifying the control constants in the arithmetic unit 7 including the proportional derivative control circuit and the arithmetic unit 8 including the proportional integration control circuit.

The tension of the warp T is almost set by the loom operation command. Warp tension P ₀
In this state, the operation of the loom is started. The diameter Dx of the warp beam 1 at this time is calculated by the formula (7) immediately after the loom is operated (about several seconds).
Calculated based on the calculated warp beam diameter Dx
Based on the maximum diameter Dmax of the warp beam used and the compensation gain Kx is reset as follows.

Kx = (1 / ΔP) · Dx / Dmax (13) Thus, the equation (10) becomes as follows.

G (s) = C (s) ・ Gg ・ πD ・ E ・ (1 / ΔP) ・ Dx / Dmax D≈Dx, so the warp elastic modulus E = ΔP / (πD ・
Gg) can be expressed as ΔP / (πDx · Gg). Therefore, G (s) = C (s) · D / Dmax (14) Equation (14) guarantees the stability of the warp delivery control with respect to the warp beam diameter D of Dmax or less, like Equation (12). And
The resetting of the compensation gain is represented by the change from the straight line L1 to the straight line L2 in the graph of FIG. That is, the warp beam diameter D ₀
When the warp beam diameter D is D ₀ or more, the value of G (s) / C (s) indicated by the straight line L1 corresponding to the compensation gain set at Becomes unstable, but G (s) / C represented by the modified straight line L2
Even when the value of (s) is D ₀ <D ≦ Dmax, it does not exceed 1. Therefore, even if the warp beam of the same warp type is replaced and the diameter of the warp beam becomes larger than the diameter of the warp beam for which the tension was set before the replacement, resetting the compensation gain after setting this tension will not The stability of the delivery control is ensured, and it is not necessary to change the setting of the control constants of the calculators 7 and 8 even when the warp beam diameter is changed and the warp type is changed.

When the kind of warp is changed, the tension difference ΔP related to the elastic modulus E of the warp may be measured again to set the compensation gain.

Effect of the Invention As described in detail above, in the first invention, the reciprocal of the difference between the warp tension detected first and the warp tension detected after a predetermined amount of rotation of the warp feed-out motor is calculated as the compensation gain for the warp elastic coefficient. Therefore, the stability of the warp delivery control for the warp beam diameter equal to or smaller than the warp beam diameter when the compensation gain is set is guaranteed by the compensation gain. In the second invention, the compensation gain is reset based on the warp beam diameter larger than the warp beam diameter when the compensation gain is set and the warp beam diameter measured immediately after the loom operation after the compensation gain setting. Since the warp beam diameter area where stable warp delivery control can be performed is expanded, the same type of warp beam exchange is performed in the increasing direction of the warp beam diameter, and the compensation gain is not set. In this case, the stability of the warp delivery control is guaranteed as in the case of the first invention. Moreover, there is an excellent effect that the compensation gain can be set without going through the setting operation of the control constant in the warp delivery control system.

[Brief description of drawings]

The drawings show one embodiment of the present invention. FIG. 1 is a block diagram of a warp delivery control mechanism, FIG. 2 is a block diagram showing a feedback system of the warp delivery control mechanism, and FIG. It is a graph for explaining resetting. Warp beam 1, warp tension detector 6, controller C1 as rotation control means, set warp beam diameter Dmax, compensation gain Kx, warp feed motor M2, warp T.

Front Page Continuation (72) Inventor Takayuki Hiraki, 338, Kuze-Denjo-cho, Minami-ku, Kyoto-shi, Kyoto Within Simpo Industry Co., Ltd. (56) Reference JP 59-157354 (JP, A) JP 1-104859 (JP, A) JP 1-148842 (JP, A)

Claims (2)

[Claims] 1. A warp feeding motor independent of a loom drive motor, a warp tension detecting means, and a warp feeding motor based on a comparison calculation of the warp tension detected by the warp tension detecting means and the set warp tension. The compensation gain for the warp elastic coefficient is incorporated in the loop transfer function in the feedback system including the means for controlling the rotation, and the difference between the warp tension detected in advance and the warp tension detected after the warp feed motor is rotated by a predetermined amount. Warp feed-out control method in a loom, wherein the reciprocal of the above is set as the compensation gain. 2. A warp feeding motor independent of a loom drive motor, a warp tension detecting means, and a warp feeding motor based on a comparison calculation of the warp tension detected by the warp tension detecting means and the set warp tension. The compensation gain for the warp elastic coefficient is incorporated in the loop transfer function in the feedback system including the means for controlling the rotation, and the difference between the warp tension detected in advance and the warp tension detected after the warp feed motor is rotated by a predetermined amount. The reciprocal of is set as the compensation gain, and the ratio of the warp beam diameter measured immediately after starting the loom after this setting and the warp beam diameter preset to a value larger than the measured warp beam diameter is set as the compensation gain. A warp feed-out control method for a loom, which resets a multiplied value as a compensation gain.