JPH02118137A - Method for controlling picking in air jet type loom - Google Patents

Abstract

PURPOSE:To optimally control air consumption and reduce energy consumption by correcting and controlling air pressure and jetting time so as to reduce the air consumption based on sensed values of air consumption in a picking nozzle. CONSTITUTION:An air consumption is sensed with an air flowmeter 7 and jetting time is corrected and controlled according to the sensed values. A change in picking state according thereto is compensated with a change in air pressure. The air pressure and jetting time in combination are controlled in the direction to reduce the air consumption. Thereby, the required picked state is satisfied.

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a weft insertion control method for an air injection loom.

<Prior Art> Conventionally, as a weft insertion control method for air injection looms, when weft insertion is performed by injecting pressurized air from a weft insertion nozzle (main nozzle) for a predetermined injection time, the weft insertion state of the weft, For example, by detecting the timing at which the weft reaches the opposite side of the weft insertion or the weft insertion speed, and controlling the air pressure supplied to the weft insertion nozzle so that this becomes a constant target value, regardless of changes in the yarn type, etc. It is known that the optimum weft insertion condition can always be achieved (Japanese Unexamined Patent Application Publication No. 114-114).
(See Publication No. 59).

<Problems to be Solved by the Invention> However, in such a conventional weft insertion control method, the timing at which the weft reaches the opposite weft insertion side or the weft insertion speed is detected and the air flow to the weft insertion nozzle is controlled. Since only the pressure is controlled, there is a problem that the amount of air consumed may increase.

SUMMARY OF THE INVENTION In view of these conventional problems, it is an object of the present invention to provide a weft insertion control method for an air injection loom, which can also optimally control air consumption and save energy.

<Means for Solving the Problems> For this reason, the present invention detects the weft insertion state of the weft when performing weft insertion by injecting pressurized air from a weft insertion nozzle for a predetermined injection time, and detects the weft insertion state. In an air injection loom that controls the air pressure supplied to the weft insertion nozzle according to the Then, the jetting time of the weft insertion nozzle is corrected and controlled.

<Function> In other words, the air pressure to the weft insertion nozzle is controlled preferentially according to the weft insertion state (for example, the timing of the weft arriving at the opposite side of the weft insertion or the weft insertion speed, etc.) to meet the required weft insertion condition. The weft insertion condition is satisfied, but the weft insertion condition also depends on the injection time, and there are essentially many combinations of air pressure and injection time to satisfy the required weft insertion condition.

On the other hand, if the amount of air consumed by the weft insertion nozzle is detected and the injection time is corrected and controlled accordingly, the weft insertion state will change according to this injection time, and the air will be released in order to maintain the required weft insertion state. Pressure changes. In other words, the combination of air pressure and injection time is controlled while satisfying the required weft insertion condition.

Therefore, the injection time is controlled in a certain direction to provide a combination of air pressure and injection time that reduces the amount of air consumed.

<Example> The present invention will be explained in detail below.

FIG. 1 shows a first embodiment.

The main nozzle 1, which is a weft insertion nozzle, inserts the weft yarn 2 by jetting air. Air is supplied via an electropneumatic proportional valve 4° surge tank 20 and an electromagnetic shut-off valve 5. Therefore,
Air pressure to the main nozzle 1 is controlled by an electropneumatic proportional valve 4, and injection timing (injection start timing and injection end timing) of the main nozzle 1 is controlled by an electromagnetic on-off valve 5.

Here, a photoelectric sensor 6 for detecting the weft arrival timing is provided on the side opposite to the weft insertion path of the weft insertion path of the weft 2 inserted by air injection from the main nozzle 1.

Further, upstream of the air tank 3 in the pressurized air supply path, for example, a hot wire type air flow meter 7 for detecting air consumption (air flow rate) is provided. Note that the air flow meter 7 may be provided downstream of the air tank 3.

The air pressure control system includes a weft arrival timing target signal setter 8 that can preset a target value (for example, 240'') for the weft arrival timing. , and the target value from the weft arrival timing target signal setter 8 are input to the comparator 9.The comparator 9 compares the weft arrival timing with the target value, and calculates the control deviation from the controller 1o.
Output to. The regulator 10 generates an air pressure command voltage according to the control deviation and applies it to the electropneumatic proportional valve 4 . The electropneumatic proportional valve 4 controls the air pressure to be proportional to the voltage.

That is, as the weft insertion state of the weft 2, the weft arrival timing to the opposite weft insertion side is detected by the photoelectric sensor 6, and this weft arrival timing is made to match the target value set by the weft arrival timing target signal setting device 8. , comparator 9. The air pressure to the main nozzle 1 is feedback-controlled by the electropneumatic proportional valve 4 via the regulator 10.

The injection timing control system includes an injection timing target signal setter 11 that can preset target values of injection timing (injection start timing and injection end timing). When the injection start timing and injection end timing set by the injection timing target signal setter 11 match the loom main shaft angle detected by the loom angle sensor 12, the comparator 13 outputs a voltage signal (ON, OF
F signal), and drive power is output to the electromagnetic on-off valve 5 via the driver amplifier 14.

Further, an injection timing target signal setting corrector 15 is connected to the injection timing target signal setting device II, and a signal from the air flow meter 7 is input to the injection timing target signal setting corrector 15.

As a result, the amount of air consumed by the main nozzle 1 is detected, and the injection time of the main nozzle 1 (
Here, the loom main shaft angle (from the injection start timing to the injection end timing) is corrected and controlled.

Next, the injection time correction control will be explained according to the flowchart shown in FIG.

In step 1 (denoted as Sl in the figure; the same applies hereinafter), the air flow rate Q detected by the air flow meter 7 is input.

In step 2, a timing table for shortening the injection time is created. In other words, if the current injection start timing (before shortening) is 90° and the injection end timing is 220°, then according to the change algorithm, the injection start timing is set to 90°.
A timing table is created with the injection end timing set at 2° and the injection end timing set at 218°.

Therefore, this timing table is as shown in the following table, for example.

In step 3, the injection time reduction timing (injection start timing 92°, injection end timing 218°) is preset according to this timing table.

As a result, weft insertion is performed by the main nozzle l based on the injection start timing and injection end timing with the shortened injection time.

In step 4, there is a delay for a predetermined time until the air pressure control stabilizes. In other words, when the injection time is shortened, the weft arrival timing inevitably becomes delayed, and to compensate for this, the air pressure is increased to restore the weft arrival timing to the original value, and the weft arrival timing is brought to the target value with the shortened injection time. Wait for the combination of air pressure and injection time to be satisfied.

In step 5, the airflow iiQ detected by the airflow meter 7 is input.

In step 6, the air flow rate Q before the injection time reduction detected in step 1 is compared with the air flow rate Q2 after the injection time reduction detected in step 5, and it is determined that the air flow rate has decreased (Q!
<Q+).

If YES here, it means that the air consumption has been controlled in a direction that reduces it, so repeat steps 2 to 6 to further shorten the injection time to find the air that minimizes the air consumption. Controlled by a combination of pressure and injection time.

If No, execute steps 7-11.

In step 7, a timing table for extending the injection time is created. In other words, if the current injection start timing (before extension) is 92° and the injection end timing is 218°, a timing table with the injection start timing at 90° and the injection end timing at 220° is created according to the change algorithm. .

In step 8, the injection time extension timing (injection start timing 90°, injection end timing 220°) is preset according to this timing table.

As a result, weft insertion is performed by the main nozzle l based on the injection start timing and injection end timing with the extended injection time.

In step 9, there is a delay for a predetermined time until the air pressure control is stabilized. In other words, when the injection time is extended, the weft arrival timing inevitably becomes earlier, so the air pressure is reduced to restore the weft arrival timing to the original value, and the weft arrival timing is made to meet the target value with the extended injection time. Wait until the combination of air pressure and injection time is determined.

In step 10, the airflow IQ detected by the airflow meter 7 is input.

In step 11, the air flow rate Q2 before the injection time extension detected in step 6 is compared with the air flow rate Q after the injection time extension detected in step 10, and it is determined that the air flow rate has decreased (Q
3 <Qz).

If YES here, the air consumption has been controlled in the direction of decreasing, so repeat steps 7 to 11 and further extend the injection time to find the air that minimizes the air consumption. Controlled by a combination of pressure and injection time.

If NO, proceed to steps 2 to 6.

FIG. 3 shows a second embodiment.

In this embodiment, air consumption is detected by calculation instead of using an air flow meter, and the same parts as in the previous embodiment are denoted by the same reference numerals and the explanation thereof will be omitted.

The difference is that the air flow meter has been abolished, and the injection timing target signal setting corrector 15 uses the air pressure command voltage of the regulator 10 (or numerical information before D/A conversion) and the current value of the injection timing target signal setting device 11. Enter the value (preset data).

Here, the air consumption (air flow rate) Q can be calculated using the following equation.

Q= (K+ xv p 10c) X ((Tvc
Tvo)-Tk)XK.

Vp: Air pressure command voltage Tvc: Injection end timing 'rvo: Constant coefficient c at the injection start timing, 'rk: Constant Therefore, the injection timing target signal setting corrector 15 first adjusts the Air pressure command voltage (or numerical information before D/A conversion) Vp and injection timing target signal setter 1
1, the current value (preset data) of injection start timing T vo and injection end timing 'I'we are input, the air flow rate Q is calculated according to the above calculation formula, and the air flow itQ based on this calculation is calculated. , performs injection time correction control.

The injection time correction control in this case is shown in the flowchart of FIG.

The difference is in step 1 above. Step 5゜Step 10 is respectively Step la, lb, Step 5a
, 5b, and steps lOa and 10b, in which the air pressure command voltage ■p, the injection start timing Tv0, and the injection end timing Tvc are manually input in each previous stage, and the air flow rate Q is calculated in each subsequent stage.

In the above embodiment, both the injection start timing and the injection end timing are changed when modifying the injection time, but only one of them may be changed.

<Effects of the Invention> As explained above, according to the present invention, it is possible to optimally control not only the insertion state of the weft threads but also the amount of air consumption, thereby saving energy.

[Brief explanation of drawings]

FIG. 1 is a system diagram of a first embodiment of the present invention, FIG. 2 is a flowchart of injection time correction control of the first embodiment, and FIG. 3 is a system diagram of a second embodiment of the present invention. FIG. 4 is a flowchart of injection time correction control according to the second embodiment. ■...Main nozzle 2...Weft thread 3...Air tank 4...Electro-pneumatic proportional valve 5...Solenoid on-off valve 6
...Photoelectric sensor 7...Air flow meter 8
...Weft arrival timing target signal setter 9...
Comparator lO...Adjuster 11...Injection timing target signal setter 12...Loom angle sensor
13... Comparator 14... Driver amplifier 15.
... Injection timing target signal setting corrector patent applicant Nissan Motor Co., Ltd. Representative Patent attorney Fujio Sasashima Figure 2 Figure 4

Claims (1)

[Claims] When performing weft insertion by injecting pressurized air from the weft insertion nozzle for a predetermined injection time, the weft insertion state of the weft is detected and the air pressure supplied to the weft insertion nozzle is controlled according to the weft insertion state. In the air injection loom, the amount of air consumed by the weft insertion nozzle is detected, and based on the detected value, the jetting time of the weft insertion nozzle is corrected and controlled so as to reduce the amount of air consumption. A method for controlling weft insertion in an air-injection loom.