JPH0797747A - Weft-insertion control method for jet loom and apparatus therefor - Google Patents

Abstract

PURPOSE:To maximize the operation efficiency of a loom by keeping the optimum stretch time in weft insertion. CONSTITUTION:This apparatus for the control of weft-insertion is provided with a measuring means 13 to measure the stretch time Ts, a comparison means 14 to compare the stretch time Ts with a preset stretch time Tso and output the deviation DELTATs=Tso-Ts and a rotational speed controlling apparatus 21 to control the rotational speed of a loom based on the deviation signal S3 transmitted from the comparison means 14. When the stretch time Ts is varied, the rotational speed of the loom is controlled by the rotational speed controlling apparatus 21 to eliminate the deviation (DELTATs=0) and, accordingly, the loom can be operated at the maximum rotational speed while keeping the stretch time Ts to the preset stretch time Tso.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jet loom weft insertion control method and apparatus capable of maximally improving overall operating efficiency while maintaining stable weft insertion operation in a jet loom.

[0002]

2. Description of the Related Art In a jet loom, a weft is inserted using a fluid jet of water or air.
The behavior of the weft at that time is roughly as follows (FIG. 7).

Now, at the loom mechanical angle θ = θs, the weft starts to fly, and at θ = θe, the predetermined length L = L.
Weft insertion of o shall be completed. That is, the weft is
At the start angle θs, when weft insertion into the warp shed is started, at the reaching angle θe, the weft insertion side is reached,
The rear end portion is locked by the length measurement storage device. However, in the figure, the flight speed of the weft is considered to be the same in all the strokes.

The weft thread whose rear end is locked at the reaching angle θe is temporarily stretched to the opposite weft insertion side by inertia,
Then, since there is a tendency to recoil toward the weft insertion side, the tip of the weft yarn after the reaching angle θe greatly expands and contracts and vibrates. Therefore, it is preferable that the sub-nozzle on the most downstream side of the weft flight path, the stretch nozzle arranged on the opposite weft insertion side, etc. be continuously operated even after the reaching angle θe to apply tension to the weft. The vibration cycle of the weft at this time is almost constant regardless of its amplitude (solid line and dotted line in the figure). This is because the vibration cycle of the weft is determined by the elasticity of the weft.

On the other hand, the weft yarn thus inserted is restrained by the warp yarn by closing the warp yarn opening at θ = θh. Note that the restraint angle θh at this time
Is preferably set to be delayed with respect to the reaching angle θe by one cycle of the vibration cycle of the weft. This is because if the weft yarn is restrained after one cycle of the vibration period, the weft yarn at that time has a predetermined length Lo, and there is no possibility that loosening defects or the like will occur in the woven fabric. However, the restraint angle θh may be set so as to correspond to a time after the reaching angle θe and after a long time sufficient for the vibration of the weft to converge.

On the basis of such knowledge, the Applicant has set a constant time difference (hereinafter referred to as stretching time) from the time when the weft reaches the opposite weft insertion side to the time when the weft is constrained by the warp. A weft-insertion control method characterized by controlling has been proposed (Japanese Patent Laid-Open No. 2-300350). However, this one aims to realize stable weft insertion operation even when the loom rotational speed fluctuates, by setting the weft insertion fluid pressure and the start angle θs as the control target. I am trying.

[0007]

According to the conventional technique, the weaving condition of the loom is controlled so that a predetermined stretching time can be secured. Therefore, when the number of revolutions is small, There has been a problem that the time from the start of weft insertion to the completion of the weft insertion becomes too long and the operation efficiency is reduced. That is, the loom at this time was forced to operate at a low speed in spite of the room for further increasing the rotation speed, so that the operating efficiency was suppressed to a low level, which was extremely unreasonable.

Therefore, in view of the problems of the prior art, an object of the present invention is to maximize the operating efficiency of the loom by maintaining the stable weft insertion operation by controlling the rotational speed of the loom to be controlled. It is to provide a jet loom weft insertion control method and a device therefor.

[0009]

Means for Solving the Problems The structure of the first invention according to this application for achieving the above object is, when weft is inserted in a jet loom, when the weft reaches an anti-weft insertion side, The gist of the invention is to detect the restraint time when the inserted weft yarn is restrained by the warp yarn and to control the rotation speed of the loom so that the stretch time becomes the set stretch time.

The set stretch time can be constant with respect to the rotation speed of the loom or can be dependent on the rotation speed of the loom.

According to the structure of the second invention, the stretching time is determined based on the constraint angle detector for detecting that the mechanical angle of the loom has reached the constraint angle, and the weft signal from the weft feeler and the output signal of the constraint angle detector. The measuring means for measuring, the comparing means for comparing the stretch time from the measuring means with the set stretch time, and the rotation speed control device for controlling the rotation speed of the loom based on the error signal from the comparing means are provided. And

A weft insertion control device may be branched and connected between the comparison means and the rotation speed control device, and the weft insertion control device may be operated prior to the rotation speed control device.

[0013]

According to the structure of the first invention, the loom comprises:
Since the number of rotations is controlled so that the stretch time becomes the set stretch time, there is no unnecessary waiting time exceeding the set stretch time between the reaching angle and the restraint angle, and the maximum stretch is always achieved. It can be operated at a rotational speed. However, the stretching time is
The time difference from the arrival time when the weft reaches the opposite weft insertion side to the time when the weft inserted is constrained by the warp, that is, the time difference from the arrival angle to the constraint angle is measured.

The set stretch time is generally sufficient if it is constant regardless of the rotation speed of the loom, but it may be linearly changed with respect to the rotation speed of the loom depending on the rotation speed of the loom. If a sufficiently long set stretch time is set in order to restrain the weft thread after the expansion and contraction vibration of the weft thread has settled, the weft thread vibration will occur for a short time when the loom rotation speed is low and the weft insertion speed is low. It is considered that it takes a long time to converge when the loom rotation speed is high and the weft insertion speed is high.

According to the second aspect of the invention, the measuring means measures the stretching time, the comparing means compares the measured stretching time with the set stretching time, and the rotation speed control device makes the error from the comparing means. Since the rotation speed of the loom is controlled based on the signal, the first invention can be implemented as it is as a whole.

If the weft insertion control device is branched and connected between the comparison means and the rotation speed control device, the weft insertion control device changes the weft insertion condition by changing the weft insertion condition prior to the rotation speed control device. After matching the set stretch time, the rotation speed control of the loom by the rotation speed control device becomes effective. That is, even when the responsiveness of the rotation speed control device is not sufficiently fast, the overall responsiveness can be improved.

[0017]

Embodiments Embodiments will be described below with reference to the drawings.

The weft insertion control device for the jet loom comprises a weft feeler 11, a restraint angle detector 12, a measuring means 13,
The comparison means 14 and the rotation speed control device 21 are provided (FIG. 1).

It is assumed that the weft feeler 11 is installed on the non-weft insertion side of a woven cloth (not shown), and detects that the weft inserted has reached the anti-weft insertion side, and outputs a weft signal S1. The weft signal S1 is input to the measuring means 13.

The output of an encoder EN for detecting the mechanical angle θ of the loom is connected to the restraint angle detector 12, and a setting device 12a for setting a predetermined restraint angle θh is attached. The restraint angle detector 12 detects θ = θh and generates an output signal S2. The output signal S2 is measured by the measuring means 13.
Is also entered in. The output of the measuring means 13 is connected to the rotation speed control device 21 via the comparing means 14,
A drive motor M is connected to the output of the rotation speed control device 21. However, the drive motor M is a drive motor of a loom (not shown). Further, the comparing means 14 is provided with a setting device 14a.

The output of the comparison means 14 is input to the correction amount calculator 21a of the rotation speed control device 21 as an error signal S3 (FIG. 2). Further, the output of the correction amount calculator 21a is connected to the drive motor M via a summing point 21b and a control amplifier 21c, and a setter 21d is connected to another summing terminal of the summing point 21b. There is.

The loom is assumed to be an air jet loom. That is, the weft yarn is supplied from the yarn feeder and stored in the length measuring and storing device, unwound from the length measuring and storing device at a predetermined loom mechanical angle θ = θs, and is guided into the warp opening by the air jet from the weft inserting nozzle. Be inserted in Weft,
When the predetermined length is unwound from the length measurement storage device, the rear end portion is locked, and the leading end portion reaches the position of the weft feeler 11 on the side opposite to the weft insertion at the final stage of weft insertion. At this time, the above-mentioned stretching vibration occurs in the weft. The weft feeler 11 can also generate a weft signal S1.

In the setter 12a, the weft inserted is
The loom mechanical angle θ when constrained by the closing warp is set as the constraint angle θh. Therefore, the restraint angle detector 12 can detect θ = θh, detect the restraint time at which the warp yarn restrains the weft-inserted weft yarn, and generate the output signal S2.

The measuring means 13 measures the stretch time Ts based on the weft signal S1 and the output signal S2 and outputs it to the comparing means 14. This is because the measuring means 13 can measure the time difference from the arrival time point at which the weft yarn signal S1 is generated to the restraint time point at which the output signal S2 is generated, and can use it as the stretching time Ts.

The setting stretcher T has a set stretch time T.
Set so. Therefore, the comparison means 14 is the measurement means 13
By comparing the stretch time Ts from the set stretch time Tso with the set stretch time Tso, the deviation ΔTs is obtained as the error signal S3.
= Tso-Ts can be output to the rotation speed control device 21.

The rotation speed control device 21 includes a correction amount calculator 21.
The deviation ΔTs is converted into the correction amount ΔN of the rotational speed via a. Further, the set speed No is set in the setter 21d. Therefore, the summing point 21b is the target rotation speed No1.
= No + ΔN can be output to the control amplifier 21c, and the rotation speed control device 21 as a whole can drive the drive motor M
Rotation speed of the loom, that is, the rotation speed N of the loom
Can be controlled. However, the control amplifier 21c
Is to feed back the rotation speed of the drive motor M via a speed detector (not shown) to control the rotation speed of the drive motor M to the target rotation speed No1.

The above series of control operations can be illustrated as shown in FIG. In FIG. 3, the horizontal axis represents the time axis t, and the vertical axis passing t = 0 represents the rotational speed N of the loom. However, the horizontal axis is set to pass through the set rotation speed N = No, and the vertical axis is set to the minimum value N1 and maximum value N2 of the rotation speed N of the loom. However, N = N1, N = N
For each position of 2, set point X at an appropriate position on the vertical axis, and
From the point X to N = N, where xo is the distance from the horizontal axis to
1, and the distances x1 and x2 to N = N2 are x1 = (No / N
1) xo, x2 = (No / N2) xo.

Next, when the loom rotational speed N = No, the loom mechanical angle θ = 0 (degrees), θ = θs, θ = θe, θ = θh
, T = −ta, t corresponding to θ = 360 (degrees)
= 0, t = te, t = th, t = tb are defined on the horizontal axis. However, θs is the start angle, θe is the arrival angle, and θh is the restraint angle. At this time, the point X and t = −t on the horizontal axis
Straight lines Ba, Bh, Bb connecting a, t = th, and t = tb
Respectively, when the rotation speed N of the loom fluctuates, θ = 0 (degrees), θ = θh, θ = with reference to the start angle θs.
Each timing of 360 (degrees) represents a temporal change in inverse proportion to the rotation speed N of the loom. For example,
When t = th1 and t = th2, which correspond to the intersection of each straight line passing through N = N1 and N = N2 and parallel to the horizontal axis and the straight line Bh, respectively, are the loom rotational speeds N = N1 and N = N2, respectively. , The restraint angle θh is t = th1 and t = th2 from the start angle θs.
Indicates that it will be delayed only. However, th1 = (No / N1)
Th> th and th2 = (No / N2) th <th.

On the other hand, the time difference (th-te) on the horizontal axis is
The stretch time Ts at the set rotation speed N = No, that is, the set stretch time Tso is represented. Therefore, when a straight line Be passing through t = te on the horizontal axis and parallel to the straight line Bh is taken, the straight line Be has a reaching angle θe with respect to the rotational speed N of the loom when the stretching time Ts = Tso. Shows how it changes. That is, when the stretching time Ts is reduced to Ts = Tsa <Tso for some reason while the loom is operating at the set rotational speed N = No, the rotational speed N of the loom should be reduced to N = Na <No. As a result, the stretching time Ts = Tso can be maintained, and when the stretching time Ts increases to Ts = Tsb> Tso,
By accelerating to N = Nb> No, Ts = Tso can be maintained.

Therefore, the correction amount calculator 21a of the rotation speed control device 21 uses the deviations ΔTs = Tso−Tsa and ΔTs = Tso−.
Corresponding to Tsb, correction amount ΔN = Na −No, ΔN = Nb
It may be configured to output -No. At this time, the set stretch time Tso is constant regardless of the rotation speed N of the loom.

[0031]

Other Embodiments The straight line Be in FIG. 3 is not parallel to the straight line Bh (FIG. 4), and the set stretch time Tso can be made dependent on the rotational speed N of the loom. For example, in FIG. 4, the straight line Be is set so that the set stretch times Tsc and Tsd at N = N1 and N = N2 are Tsc <Tso <Tsd. At this time, stretch time T
The rotation speeds N of the loom corresponding to s = Tsa and Ts = Tsb are N = Na1> Na and N = Nb1 <Nb, respectively, and the rotation speed control device 21 as a whole has such a rotation speed N of the loom. It may be operated so as to realize. It should be noted that the operation of the rotation speed control device 21 is performed by setting either the set stretch time Tso set in the setting device 14a or the correction amount ΔN calculated by the correction amount calculation device 21a to the rotation speed N of the loom.
It can be realized by using the function of.

When the loom carries out multi-color weft insertion of n colors (n ≧ 2), n measuring means 13, 13, ... Are provided for each color (FIG. 5), and the weft feeler 11 and each measuring means 13 are provided. An AND gate 16 is provided between the measuring means 13 and
The outputs of 13 ... Can be connected to the comparison means 14 via the minimum value selection means 17. In addition, each AND gate 1
6 is a weft selection signal Swi (i = 1, 2) corresponding to each color.
... n) is also input.

Each measuring means 13 measures the time difference between the weft signal S1 for each color selected by the weft selection signal Swi and the output signal S2 of the restraint angle detector 12 to obtain the stretching time Tsi corresponding to each color. (I = 1, 2, ...
n) is detected and output to the minimum value selection means 17. Therefore, the minimum value selection means 17 can output the minimum value of the stretch time Tsi as the stretch time Ts to the comparison means 14, and the rotation speed control device 21 at this time determines the minimum stretch time Tsi. The rotation speed N of the loom can be controlled by paying attention.

A weft insertion control device 22 can be branched and connected between the comparison means 14 and the rotation speed control device 21 (FIG. 6). However, the weft insertion control device 22 includes the correction amount calculator 22a, the addition point 22b, and the timing controller 2.
2c are cascaded, and the control target is the weft inserting nozzle N.
It is an on-off valve V for operating Z. The output of the correction amount calculator 22a is branched and connected to the rotation speed control device 21. A setting device 22d is connected to the other addition terminal of the combining point 22b, and the loom mechanical angle θ from the encoder EN is input to the timing controller 22c.

Assuming that the set value θso of the start angle θs is set in the setter 22d, the timing controller 22c has a deviation ΔTs = 0 from the comparison means 14,
When the correction amount Δθs = 0 from the correction amount calculator 22a, the open / close valve V can be opened for a predetermined time at θ = θso to execute weft insertion. Further, the rotation speed control device 21 at this time maintains the rotation speed N = No of the loom.

On the other hand, when the comparing means 14 outputs the deviation ΔTs ≠ 0, the correction amount calculator 22a outputs the correction amount Δθs ≠ 0. Therefore, the timing controller 22c outputs θ =
Weft insertion is started at θso + Δθs, and start angle θs
Can be promptly subjected to correction control. Further, at this time, since the correction amount Δθs is also input to the rotation speed control device 21, the rotation speed control device 21 increases or decreases the rotation speed N of the loom based on the correction amount Δθs, and finally the deviation ΔTs
= 0 and the correction amount Δθs = 0 are realized. That is, at this time, the weft insertion control device 22 operates prior to the rotation speed control device 21, and the deviation ΔTs can be eliminated more quickly. Note that the weft insertion control device 22 may be a pressure adjustment valve for adjusting the fluid pressure supplied to the weft insertion nozzle NZ, instead of using the open / close valve V as the control target.

In the above description, the correction amount calculator 21
Each of a and 22a may include a dead band element inside. For example, the correction amount calculator 21a of FIG. 2 may respond only when the deviation ΔTs of a certain amount or more is input, and output the correction amount ΔN of a certain amount. Also,
In each of the above embodiments, the arrival time point when the weft reaches the side opposite to the weft insertion side indicates that the weft yarn of a predetermined length is unwound from the length measuring storage device, instead of the weft signal S1 from the weft feeler 11. The detection may be performed by a signal or a signal indicating that the rear end portion is locked. On the other hand, at the time of restraint, instead of the output signal S2 of the restraint angle detector 12, for example, a sensor for detecting the opening operation of the heddle frame may be provided and detected by a signal indicating that the warp shed is closed. . The present invention is applicable not only to the air jet loom but also to the water jet loom.
It goes without saying that it can be applied as it is.

[0038]

As described above, according to the first aspect of the present application, by controlling the number of revolutions of the loom such that the stretch time becomes the set stretch time, the loom can always set the stretch time. Since it is possible to operate at the maximum number of rotations that can ensure the above, there is an excellent effect that a stable weft insertion operation can be maintained and the overall operation efficiency can be maximized.

According to the second aspect of the invention, the measuring means measures the stretch time based on the weft signal from the weft feeler and the output signal of the restraint angle detector, and the comparing means compares the stretch time with the set stretch time. However, since the rotation speed control device can control the rotation speed of the loom based on the error signal from the comparison means, the first invention can be implemented as it is.

[Brief description of drawings]

[Figure 1] Overall configuration block diagram

[Fig. 2] Block diagram of main parts

[Fig. 3] Operation explanatory diagram

FIG. 4 is a view corresponding to FIG. 3 showing another embodiment.

FIG. 5 is a block diagram of a main part block showing another embodiment (1).

FIG. 6 is a block diagram of a main part block showing another embodiment (2)

[Fig. 7] Operation explanatory diagram

[Explanation of symbols]

Tso, Tsc, Tsd ... Set stretch time Ts, Tsa, Tsb, Tsi (i = 1, 2 ... n) ... Stretch time N ... Loom rotational speed θ ... Loom mechanical angle θh ... Restraint angle S1 ... Weft signal S2 ... Output Signal S3 ... Error signal 11 ... Weft feeler 12 ... Restraint angle detector 13 ... Measuring means 14 ... Comparison means 21 ... Rotation speed control device 22 ... Weft insertion control device

Claims (5)

[Claims] 1. When weft-inserting a weft in a jet loom, the time when the weft reaches the opposite weft-insertion side and the time when the weft is restrained by the warp are detected,
A weft insertion control method for a jet loom, which comprises controlling the number of revolutions of the loom so that the stretching time becomes a set stretching time. 2. The weft insertion control method for a jet loom according to claim 1, wherein the set stretch time is constant with respect to the number of revolutions of the loom. 3. The jet loom weft insertion control method according to claim 1, wherein the set stretch time depends on the number of rotations of the loom. 4. A restraint angle detector for detecting that the mechanical angle of the loom has reached a restraint angle, and measuring means for measuring the stretch time based on a weft signal from a weft feeler and an output signal of the restraint angle detector. And a comparison means for comparing the stretch time from the measuring means with the set stretch time,
A weft insertion control device for a jet loom, comprising a rotation speed control device for controlling the rotation speed of a loom based on an error signal from the comparison means. 5. A weft insertion control device is branched and connected between the comparison means and the rotation speed control device, and the weft insertion control device operates prior to the rotation speed control device. Item 4. A jet loom weft insertion control device according to item 4.