Tenter feeler with enhanced optical sensitivity and its sensing method

Abstract

The invention provides a tenter feeler with enhanced optical sensitivity and its sensing method. The tenter feeler with enhanced optical sensitivity and its sensing method for a tenter comprise a first light sensor sensing general fabric and a second light sensor sensing blended fabric, infrared beam of about 10 KHz is used, after projection and light sensing, filtering is performed via a band-pass filter, interference signal and nosie are eliminated, the general fabric and the blended fabric can be sensed, and the fabric with relatively lower whole light reflection amount or partial light reflection amount can be sensed, and control is performed.

Description

technical field [0001] The present invention relates to a tenter feeler (Tenter feeler) used by a stenter machine and a detection method thereof. Specifically, it is composed of a first photoreceptor for detecting moving common fabrics and a second photoreceptor for detecting mixed fabrics, using 10KHz The left and right infrared light beams are projected and sensitized and then filtered to remove interference signals and noises. It can not only detect ordinary fabrics and mixed fabrics, but also detect and control fabrics with a low overall or partial reflective amount. Background technique [0002] Generally speaking, a stenter machine (Tenter Machine) is a type of drying machine that performs ironing, batik, and silk screen printing on the fabric (fiber fabric) after arranging and fixing the fabric according to the width. The pin (Pin, or clip) holds the two sides (edges) of the fabric, raises the temperature to a predetermined temperature while maintaining a predetermine...

AI Technical Summary

Problems solved by technology

[0005] like figure 2 As shown, the existing tenter detector introduces pulses of a predetermined period (or predetermined duty ratio) to the infrared light emitting device 3 to realize intermittent light emission. The high-gain Low Noise Amplifier (Low Noise Amplifier) ​​7 is amplified, and it will also be amplified due to noise, resulting in a decrease in the signal-to-noise ratio and an increase in the detection error rate

[0006] In order to obtain a high-intensity received light signal, the tenter detector introduces a large current above the rated current to the infrared light-emitting device 3 to increase the amount of light emitted, but the large current exceeding the rated current will cause the infrared light-emitting device 3 to generate heat, and the thermal load pressure will not only It will greatly shorten the service life of the device and increase the power consumption

[0007] Although the existing technology introduces a strong current about 10 times the rated current to the infrared light-emitting device 3 to obtain a cycle of 100 ms, and detects fabrics at the expense of the service life of the infrared light-emitting device 3 , however, for low light emission or light absorption Special fabrics with a high rate still have a high detection error rate or cannot be detected at all

[0008] For example, if image 3 and Figure 4 As shown, for the mixed fabric 5 alternately woven by the higher common fabric 2 of density and the lower mesh fabric 5a of density, prior art can't detect at all, therefore, as Image 6 As shown, although the normal pinning can be carried out in the common fabric 2 part, the pinning lines 21 and 22 repeatedly enter and leave the inside of the mesh fabric 5a because the mesh fabric 5a part cannot be detected, and the motor 9 and the transmission (gear box) etc.) are easy to wear and shorten the service life. On the other hand, a mechanical contact rod that can touch the fabric is set at the bottom of the tenter detector to specifically detect whether the mesh fabric moves, but this method still cannot solve the detection error rate and product defects. high rate problem

[0009] In addition, for the received optical signal, it is necessary to amplify and analyze the incident light that is projected and reflected within a short period of 100ms within the light projection time. The incoming light (fluorescent lamp, incandescent lamp, etc.) is received together. In the process of amplifying the weak received light signal, the external incoming light is also greatly amplified, resulting in detection errors and misoperations. Due to the above reasons, excessive Increase the gain of the amplifier so that less reflective fabrics cannot be detected

[0010] In addition, although the infrared photosensitive device 4 receives infrared rays, it also responds to other visible light and even ultraviolet rays at the same time, causing the signal-to-noise ratio (S / N ratio) to deteriorate and reduce the detection efficiency. normal detection

Therefore, a filter is used to filter externally incident visible light or ultraviolet light, etc., but when the operator or the object moves or operates near the stenter detector, it will also cause interference due to fluid shadows or reflected light. Detect errors and malfunctions

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