JPH06322620A - Photoelectric feeler - Google Patents

Abstract

PURPOSE:To provide an optoelectric feeler preventing the error detection of reflected light due to stains. CONSTITUTION:A photo-electric feeler is characterized by disposing a lightemitting device 1 for projecting light on a fiber, disposing a light-receiving device 2 for detecting the presence of the fiber by the deflection of the light from the fiber, disposing a light-transmitting plate 3 between the fiber and the light-emitting device 1.light-receiving device 2, and further disposing a light-shutting part 4 for shutting the light transmitted through the light- transmitting plate 3 between the light-transmitting part and the light-reflecting part of the light-transmitting plate 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflection type photoelectric feeler for detecting the presence or absence of a yarn, and more particularly to a photoelectric feeler for preventing erroneous detection due to dirt.

[0002]

2. Description of the Related Art An automatic winder is a device for winding a yarn from a yarn supplying bobbin onto a winding package. When the yarn supplying bobbin becomes empty, it is automatically replaced with a new yarn supplying bobbin. The supplied yarn can be connected to the yarn already wound in the winding package and the winding can be continued. In addition, if the yarn breaks during winding, or if a yarn defect is detected and the yarn is cut, the broken yarn or a non-defective subsequent yarn is connected to the yarn on the winding package side. Continue winding.

In order to maintain the operation of such an automatic winder, thread detection is important. A yarn feeler for detecting a yarn is provided in the yarn path from the yarn supplying bobbin to the winding package. Some yarn feelers mechanically contact the yarn to detect the presence or absence of the yarn, but as a non-contact sensor, a reflection type photoelectric sensor utilizing reflection of light from the yarn, that is, a photoelectric feeler is used. .

The reflection type photoelectric feeler is a combination of a light emitting device and a light receiving device. Light is transmitted and received when a yarn is present on the yarn path, and no yarn is present on the yarn path. Sometimes the light receiver is configured to not receive light. Specifically, the light emitting device and the light receiving device are arranged so as to be inclined with respect to each other, and are arranged so that the yarn paths coincide with the intersections of the respective optical paths.

[0005]

By the way, in a device for handling yarns such as an automatic winder, minute dust such as yarn wastes floats or scatters. This dust
However, if it adheres to the main parts of the light emitting device and the light receiving device of the photoelectric feeler, the amount of transmitted / received light decreases, and the sensitivity as a sensor lowers or malfunction occurs. That is, even if the yarn is present, there is a possibility that the detection result that the yarn is not present may appear. Therefore, it is conceivable to house the light emitter and the light receiver in a case that shields dust. The case is provided with a portion that faces the light emitter and the light receiver and transmits light. A transparent plate such as glass is used for this portion.
Therefore, the transmission plate is interposed between the light emitter and the light receiver and the yarn path. The light emitted from the light emitter passes through the transmission plate and hits the thread, and the light reflected by the thread again passes through the transmission plate and returns to the light receiver.

However, the above photoelectric feeler has another problem. As described above, the light emitter and the light receiver are housed in the case, and the transmission plate is interposed in the optical path, so that the light emitter and the light receiver are not contaminated with dust. Of course, this time, dirt is attached to the transmissive plate, but it has been found that dirt attached to the transmissive plate causes less light loss than direct dirt attached to the light emitter and the light receiver. Further, if it becomes difficult for light to pass through due to dirt adhering to the transmission plate, it is expected that a detection result indicating that there is no thread will be obtained even if thread is present. However,
When actually used, it was confirmed that a detection result indicating that there is a thread appears even though there is no thread.

As a result of diligent studies, the applicant of the present invention has found the cause of the above-mentioned malfunction that detects the presence of a thread even though there is no thread, and has found a countermeasure against it. The present invention is based on this finding (described later).

That is, an object of the present invention is to solve the above-mentioned problems and to provide a photoelectric feeler which prevents erroneous detection due to dirt.

[0009]

In order to achieve the above object, the present invention provides a light emitter for projecting light onto a yarn and a light receiver for detecting the presence or absence of the yarn by reflection from the yarn. A transmission plate is interposed between the light emitter / receiver and the thread, and the light transmitted through the transmission plate is blocked between the portion of the transmission plate where the projected light passes and the portion where the reflected light passes. The light blocking unit is provided.

[0010]

The cause of the above-mentioned malfunction of detecting the presence of the thread even though there is no thread is the reflection of light due to dirt. That is, FIG.
As shown in FIG. 3, when the dirt 41 is attached to the yarn path Y side of the transmission plate 3, the light incident on the transmission plate 3 from the light emitter is reflected by the dirt 41 into the transmission plate 3. This reflected light 4
2 is also partially reflected on the sensor side of the transmission plate 3 and returns to the yarn path side again. When the reflection is repeated in the transmission plate 3 in this way,
The reflected light 42 may happen to overlap the optical path of the light receiver. Thus, the false reflected light reaches the light receiver. Therefore, although the yarn path Y has no yarn, the reflected light is received by the light receiver, and it is determined that there is a yarn.

Therefore, in order to prevent this malfunction, it is sufficient to prevent the reflection from being repeated in the transmission plate.

With the above-described structure, the transmission plate is provided with the light blocking portion for blocking the light transmitted through the transmission plate between the portion where the projected light passes and the portion where the reflected light passes. Therefore, even if dirt is attached to the yarn path side of the transmission plate, the light that is repeatedly reflected in the transmission plate and proceeds from the light emitter side to the light receiver side is blocked by the light blocking unit and cannot reach the light receiver. . This prevents the presence of a thread from being detected even though there is no thread.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

The automatic winder has a large number of winding units 21 shown in FIG. 2 arranged side by side. The winding unit 21 can individually perform operations such as unwinding, traveling, winding, yarn splicing, and defective yarn removal. The winding unit 21 is a yarn path in which a yarn travels between a yarn supplying bobbin 24 which is placed on a peg 23 and conveyed on a bobbin supplying device 22 and a winding package 25 which is mounted on an upper portion of the winding unit 21. Y is formed, and a member having each function is provided in the middle of the yarn path Y. The yarn path Y is a virtual one,
It is indicated by a one-dot chain line in the figure. The names and functions of each part are
A tenser 27 that applies an appropriate tension to the yarn fed from the yarn feeding bobbin 24 through the guide 26, a slab catcher 28 that also detects yarn unevenness and cuts the yarn and also detects yarn running, a yarn feeding bobbin side and a winding package side. Yarn splicing device 29 for splicing the yarns, and a suction arm 30 for guiding the yarn on the yarn supplying bobbin side to the yarn splicing device 29 (in the figure, the suction arm 3
It is also shown that 0 has moved to the yarn feeding bobbin side. ), A suction arm 31 for guiding the yarn on the winding package side to the yarn joining device 29, and a winding drum 32 for rotating the winding package. The winding package 25 is detachably mounted on the winding drum 32. An intake pipe 33 is connected to the winding unit 21, and the suction arms 30 and 3 are connected.
An air stream for yarn suction can be supplied to 1. The lower end of the winding unit 21 is supported by a support pipe 34 so as to stand upright on an automatic winder, and the winding unit 21 can be tilted about the support pipe 34.

The photoelectric feeler 10 of the present invention includes a tenser 27.
It is located closer to the yarn supplying bobbin and is provided so as to face the yarn path Y. Details of the photoelectric feeler are shown in FIG. The photoelectric feeler 10 is a sealed case 1 that forms the outer shell of the photoelectric feeler 10.
1 and the case 11 houses the light emitter 1, the light receiver 2, and the detection circuit 12. Light emitter 1 is case 11
The emitting diode (LED) 13 is shown outside, and the semiconductor light emitting element 14 is covered with a package / lens 15. The LED 13 directs and emits the measurement light in the predetermined wavelength band substantially forward as shown in the drawing. The light receiver 2 is
The detection circuit 12 corresponds to the LED 13 such as a phototransistor and is sensitive to measurement light in a predetermined wavelength band.
Output an electrical signal to. The detection circuit 12 detects the presence / absence of a yarn from the presence / absence of an electric signal, and outputs it to an automatic winder controller or the like (not shown). The photoelectric feeler 10 determines that there is a yarn when the measurement light is incident on the light receiver 2.

One side of the case 11 of the photoelectric feeler 10 is composed of a transmission plate 3 made of a glass plate 16, and this transmission plate 3 can well transmit the measurement light in the above-mentioned predetermined wavelength band. The light emitter 1 and the light receiver 2 are arranged in the vicinity of the transmission plate 3 so as to be inclined with respect to each other. The degree of this inclination is set so that the main light based on the directivity of the light emitter 1 is reflected by the yarn on the yarn path Y outside the case 11 and efficiently enters the sensitive portion of the light receiver 2. There is. Due to this inclination,
The optical path for transmitting and receiving the measurement light is such that the light emitter 1, the yarn on the yarn path Y, and the light receiver 2 are connected in a V shape.

A portion (light blocking portion) 4 that does not transmit light is formed on the transmission plate 3 between the light emitting device 1 and the light receiving device 2 between the V-shaped optical paths. In particular,
The glass plate 16 is provided with a slit that crosses between the light emitting device and the light receiving device, and a black plastic plate 17 is fitted into the slit. That is, the light blocking section 4 may be any one as long as it has a low transmission characteristic in the wavelength band of the measurement light, and can be configured by interposing a black member in the middle of the glass plate 16 as in this embodiment.

Next, the operation of the embodiment will be described.

The yarn delivered from the yarn supplying bobbin 24 is guided by the guide 26 along the yarn path Y, and the photoelectric feeler 1
The presence or absence thereof is detected at 0, an appropriate tension is applied by the tenser 27, and the yarn unevenness is detected by the slab catcher 28, and then the winding package 2 is performed by the winding drum 32.
Take up to 5. When the yarn supplying bobbin 24 becomes empty, the bobbin supplying device 22 replaces it with a new yarn supplying bobbin 24. The yarn supplied from the new yarn supplying bobbin 24 is sucked by the suction arm 30 at the tip of the yarn near the guide 26, and the yarn joining device 2 is swung up by the suction arm 30.
You will be guided to 9. On the other hand, the yarn that has already been wound into the winding package has the suction arm 3 whose rear end is raised.
1 is sucked and guided to the yarn joining device 29 by swinging down the suction arm 31. In the yarn splicing device 29, the upper and lower yarns are twisted or knotted and are integrally connected. After that, the winding can be continued.

Also, when the slab catcher 28 detects a defect such as unevenness of the yarn and cuts the yarn, the yarn joining device 29 similarly uses the succeeding yarn as the yarn on the winding package side. Connect and continue winding. When the winding package 25 is fully wound, the yarn traveling is stopped and a new winding package 25 is mounted.

During the operation of the winding unit 21 as described above, the yarn must be on the yarn path Y. Photoelectric feeler 1
0 always checks whether or not there is a yarn on the yarn path Y. In this check, the light emitter 1 emits the measurement light in the predetermined wavelength band toward the yarn path Y, and the reflected light from the yarn is incident on the light receiver 2. The detection circuit 12 determines that there is a yarn when the measurement light is incident on the light receiver 2.

FIG. 3 shows how the measurement light travels when dirt 41 is attached to the yarn path Y side of the transmission plate 3 of the photoelectric feeler 10. Light entering the transmission plate 3 from the light emitter 1 is reflected in the transmission plate 3 by the dirt 41. The reflected light 42 is partially reflected also on the sensor side of the transmission plate 3 and returns to the yarn path side again. In this way, reflection is repeated in the transmission plate 3. However, the light blocking portion 4 is formed on the transmission plate 3. The reflected light 42 is blocked by the light blocking unit 4 and cannot reach the light receiver 2.

[0023]

According to the present invention, the presence or absence of a thread can be detected in a non-contact manner, and a sensor therefor is shielded from the environment such as dust. Then, even if there is no thread, the malfunction of detecting the thread is eliminated. As a result, in the operation monitoring of the automatic winder, the information as if the yarn is running even though the yarn is not running is not sent.

[Brief description of drawings]

FIG. 1 is a side view (partial cross-sectional view) of a photoelectric feeler showing an embodiment of the present invention.

FIG. 2 is a side view of a winding unit arranged in the automatic winder.

FIG. 3 is a cross-sectional view showing how measurement light travels with the photoelectric feeler of the present invention.

FIG. 4 is a cross-sectional view showing how measurement light travels with a conventional photoelectric feeler.

[Explanation of symbols]

 1 Light emitter 2 Light receiver 3 Transmission plate 4 Light blocking part Y Thread path

Claims (1)

[Claims] 1. A yarn is provided with a light emitter for projecting light and a light receiver is provided for detecting the presence or absence of the yarn by reflection from the yarn, and a transmission plate is interposed between the light emitter and the light receiver and the yarn. An optoelectronic feeler is characterized in that a light blocking section for blocking the light transmitted through the transparent plate is provided between the portion of the transparent plate where the projected light passes and the portion where the reflected light passes.