JPS6220286B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION In the process of drawing synthetic fiber tow such as nylon or polyester, and applying crimps after steam treatment, the present invention uses a thermometer provided between a steam box and a crimper, and - This relates to a device that controls the tow temperature immediately before the crimper while controlling the amount of steam injection based on a preset program in response to a stop signal.

Hitherto, a heating method using a steam box has been known as a means for heating the tow immediately before the crimper that applies the crimp. In the case of such conventional methods, the temperature of the tow immediately before the crimping device is controlled by detecting it with a surface thermometer or thermometer, and manually adjusting the amount of steam ejected in the steam box to maintain a certain temperature.
Alternatively, the atmospheric temperature inside the steam box is detected and automatically controlled so as to reach a target tow temperature.

However, the length of the temperature measuring element normally used for conventional tow temperature detection is extremely shorter than the width of the tow to be measured, making it impossible to detect the average temperature across the entire tow width. Since the temperature must be controlled based on the local temperature of the tow, there is a problem in that the temperature of the tow varies greatly. On the other hand, if the tow temperature from the start of stretching to the end of stretching is fully automatically controlled, the tow speed will increase during the tow speed increase period at the start of stretching and the tow speed deceleration period when the stretching stops, that is, the tow speed will be in an unsteady state. At the bottom, the tow temperature cannot follow the change in tow speed, and the steam control amount fluctuates, so the tow temperature fluctuates in the same way. Therefore, the crimp state of the tow during this unsteady speed time becomes unstable, which poses a problem in terms of quality and yield.

The present invention was devised in view of the various drawbacks of the prior art, and its purpose is to always be able to reliably detect the average temperature of the entire tow width, and also to detect the average temperature of the entire tow width even during an unsteady speed period such as at the start of stretching. It is an object of the present invention to provide a tow temperature control device that can control or stabilize tow temperature according to changes in speed and reliably prevent adverse effects on tow quality.

The object of the present invention is to provide a steam box for steam-processing drawn tow of synthetic fibers, a steam control valve provided in a steam line to control the amount of steam injected into the steam box, and a combination of the steam box and the crimper. A temperature sensing element is provided between the temperature sensing element and the temperature sensing element, which has a detection section having a length that is approximately the same as the toe width. An automatic temperature controller that operates the steam control valve in response to a tow temperature detection signal from a hot body, and an automatic temperature controller that is connected to the switching device and controls the opening of the steam control valve according to a preset program in response to the extension start/stop signal. This is achieved by a synthetic fiber tow temperature control device comprising a control device for controlling the temperature, and a timer that is activated when the tow speed returns to the steady drawing speed to switch the switching device to a connection circuit with an automatic temperature controller. .

The present invention will be explained below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram illustrating a tow temperature control device of the present invention, and FIG. 2 is a sectional view of a tow temperature measuring device used in the present invention. In FIG. 1, a tow 1 drawn by a drawing machine 2 passes through a steam box 4 and is heated while the tension is kept constant by a dancer roll 3. The steam box 4 is provided with at least a pair of steam jetting nozzles 5 alternately on the upper and lower surfaces of the tow. A steam control valve 6 is installed in the steam line leading to the steam jetting nozzle 5.

Reference numeral 8 denotes a temperature measuring element provided immediately in front of the crimper 10, which is composed of a temperature measuring element 11 having a length 1 equal to the width of the tow along which the temperature detecting section runs.

7 is an automatic temperature controller whose one end is connected to the temperature sensor 8 and the other end is connected to the steam control valve 6 via the switching device 13, and the steam control valve is connected in response to the tow temperature detection signal from the temperature sensor 8. 6 is activated. 12, one end is connected to the steam control valve 6 via the switching device 13, and the other end is connected to the extension start/start switch.
A control device connected to the stop signal can input a program that can arbitrarily set the opening degree of the steam control valve. Reference numeral 13 denotes a switching device for switching signals output from the control instrument 12 and the automatic temperature controller 7. At the start of stretching, the opening degree of the steam control valve 6 is changed according to an increase in the stretching speed according to a preset program. The change will be made in stages. Of course, if the stretching speed has a steep rise and takes a short time to reach a steady speed, it is also possible to fix the opening at an opening that allows a certain amount of steam to be ejected without causing any problems in the quality of the tow.

Reference numeral 9 denotes a timer whose one end is connected to the switching device 13 and the other end is connected to the stretching start and stop signals. The signal from the control instrument 12 is switched to the signal from the automatic temperature controller 7, and the tow temperature under the steady state of stretching is automatically controlled.

On the other hand, when the stretching is stopped, the signal switching device 13 is switched at the same time, and the opening degree of the steam control valve 9 can be switched in stages according to a preset program according to the lowering speed of the stretching. Of course,
Needless to say, a signal is given so that the opening degree of the steam control valve becomes 0, ie, closed, at the same time as the complete extension is stopped.

Next, a method of operating tow temperature control according to the present invention will be explained. First, at the start of stretching, the tow is hooked onto the rollers of the stretching machine while manually rotating the stretching machine 2 at a low speed, passed through the dancer roll 3, passed through the steam box 4, and then applied to the nip roller of the crimper 10. Once this work is completed, the stretching machine and crimper are started in conjunction with each other. For several minutes from the start of stretching, the opening degree of the steam control valve 6 is increased stepwise or kept constant by the control instrument 12, and the tow passing through the steam box is heated by the steam jetted from the nozzle opening. When the time including the period from the start of stretching to the steady speed has elapsed, the switching device 13 is actuated by the signal from the timer 9, and the automatic temperature controller 7 is switched to the automatic circuit, and the steam control valve is switched on at the tow temperature before the crimper 10. The amount of steam injection in the steam box is controlled by the automatic opening and closing of the steam box 6. Next, when the stretching machine stops during stretching or when the stretching is stopped when production is completed, the switching device 1
3 is switched, the circuit of the automatic temperature controller 7 is switched to the circuit of the control instrument 12, and the steam control valve 9 is switched.
The degree of opening of is gradually reduced or maintained at a constant amount, and steam is ejected.

Hereinafter, the effects of the present invention will be explained with reference to Examples.
FIG. 3 shows a comparison of changes in tow temperature and steam flow rate over time at 300,000 deniers between the conventional method (a) and the present invention (b). In the conventional method, the tow temperature is controlled by a fully automatic circuit from the start of stretching to the stop, but in this method, the tow temperature A and the steam flow rate are controlled sufficiently to account for changes in the acceleration of the tow during the unsteady speed at the start of stretching. B's control cannot follow,
Due to hunting, the tow temperature fluctuated greatly within 5 to 8 minutes after the start of stretching, causing disordered crimp and unstable quality.

In addition, in the unsteady state when the stretching is stopped, the tow speed slows down, so the heated tow radiates heat and the tow temperature drops at the measurement position, and the steam control valve is fully opened by this signal, causing steam to blow out inside the steam box. Since the amount of tow is the largest, the tow in that area is locally heated, which poses a quality problem.

On the other hand, since the present invention is configured as described above, the average temperature of the entire tow width can be detected reliably at all times, improving temperature control accuracy. Since a constant amount B' is injected within a range where the tow temperature does not change, fluctuations in the tow temperature A' are small with respect to changes in the tow speed, and it stabilizes within 2 to 3 minutes after starting, eliminating any effect on quality. In addition, since the amount of steam ejected can be reduced stepwise or switched to a constant amount at the same time as the drawing is stopped, there is no fluctuation in the amount of steam due to changes in tow speed between unsteady drawing speeds, the tow temperature is stabilized, and there is no adverse effect on quality. I was able to do it without any problems.

It goes without saying that the present invention is effective not only in improving quality but also in streamlining quality control and rationalizing personnel.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a tow temperature control system for explaining the device of the present invention, Fig. 2 is a sectional view of a thermometer for measuring tow temperature used in the present invention, and Fig. 3 is a diagram of the present invention (b) and a conventional example ( FIG. 3 is a comparison diagram illustrating the change in tow temperature over time in (a). 4: Steam box, 8: Tow temperature measuring element,
6: Steam control valve, 7: Automatic temperature controller, 1
1: Temperature sensing element, 12: Control device, 13: Switching device.

Claims (1)

[Claims] 1. A steam box for steam-processing the drawn tow of synthetic fibers, a steam control valve provided in the steam line to control the amount of steam jetted in the steam box, and a steam control valve provided between the steam box and the crimper to process the tow. A temperature measuring element having a detection part with a length that is approximately the same as the width; one end is connected to the temperature measuring element, and the other end is connected to the steam control valve via a switching device, and the temperature sensing element detects the tow temperature. An automatic temperature controller that operates the steam control valve in response to a signal and is connected to the switching device,
A control device that controls the opening degree of the steam control valve according to a preset program in response to the stretching start/stop signal, and a switching device that is activated when the tow speed returns to the steady stretching speed and switches the switching device to an automatic temperature controller. A temperature control device for synthetic fiber tow, comprising a timer for switching to a connection circuit.