JPS60157463A - Thread breakage detector - Google Patents

Abstract

PURPOSE:To detect thread breakage reliably by detecting thread breakage from a signal fed from a beam switch for passing a beam through a slit made in a pulley to be driven through motion of thread or a barrier board to be rotated by said pulley. CONSTITUTION:Upon normal feed of yarn 6, a pulley 1 is driven by said yarn 6 and rotates thus to rotate a barrier board 5 coupled through a spindle 2 with same speed thereby the beam from beam switch 7 will pass at the position of slit 5a but blocked therebetween. Consequently, the output signal from the switch 7 will be a continual waveform as shown in zone A. Upon stoppage of feeding of yarn 6, rotation of barrier board 5 will also stop to produce signal of zone B if the beam of switch 7 is at the position of slit 5a, while signal of zone B' at the position separated from the slit 5a and signal of zone C if it is at the edge of slit and since they are continuous signals, it is detected that the yarn is not fed. Consequently, thread breakage can be detected irrespective of vibration of thread.

Description

[Detailed description of the invention] [Technical portion of the invention L! F] The present invention relates to an improvement of a thread breakage detection device, and is particularly applicable to a thread breakage detection device that uses a beam switch to detect thread breakage, and is suitable for devices that move or vibrate, such as GFRP manufacturing robots. This invention relates to a thread breakage detection device suitable for use.

[Prior Art] Conventionally, yarn breakage detection devices installed in yarn winding machines, etc. are optical types that place a light beam in the path of the yarn and detect the passage of light through the yarn to detect the presence or absence of yarn breakage. , which utilizes thread tension; in other words, a contact rod to which a spring or weight is applied is brought into contact with the tensioned thread, and when the thread loses tension due to thread breakage, the position of the contact rod changes and the micro A contact type microswitch type, in which a switch is pressed and a thread breakage signal is issued, is often used.

[Problems with the Prior Art] Although these have the advantage of having a simple mechanism and being easy to use, when vibrations, fluffing, etc. of the thread occur, the detection function is significantly degraded and the method becomes unusable.

Moreover, as shown in FIG. 1, when the thread 6 is vibrating,
The thread guide 14 is swung around to promote vibration of the thread.
The optical type moves out of the detection area, and the microswitch type causes the sensor in contact with the thread to swing around, resulting in a loss of balance and malfunction.

[Object of the Invention] Therefore, an object of the present invention is to provide a thread breakage detector that can reliably detect thread breakage even when vibration occurs in the thread due to movement or vibration of the thread handling device. This is what I am trying to do.

[Structure of the Invention] In order to achieve this object, the present invention provides a thread breakage detection device that is installed in a thread feeding device to detect thread breakage, and includes a pulley that is driven and rotated by the movement of the thread, or a pulley that is rotated by the pulley. A slit is provided in the light shielding plate, a beam switch is provided to allow the light beam to pass through the slit,
The present invention is characterized in that yarn breakage is detected by a signal from the beam switch.

[Embodiments of the invention] The present invention will be described in detail below with reference to the illustrated embodiments.

Figure 1 shows GFRP (glass fiber reinforced plastic)
Showing a robot for manufacturing products. Robot body 1
1 has an arm lla, and at its tip a chopper 12 for taking and cutting glass fibers.

Glass fiber (hereinafter referred to as "yarn") 6 pieces - 15 rolled balls
The yarn passes through the yarn guide 14, passes through the yarn breakage detection device 13 according to the present invention, and is taken up by the chopper at high speed.
The cut and unillustrated spray is sprayed at a constant mixing ratio together with the fluid resin blown out by a gun.
GFRP products are manufactured. Reference numeral 17 indicates the glass fibers (chisisobud strands) which are cut and blown.

In this robot device, if a chopper pick-up failure or yarn breakage occurs, the glass fibers are not supplied and only the resin is sprayed, resulting in uneven quality and insufficient strength of the GFRP product. Therefore, if a situation occurs in which the yarn is not fed, it must be detected immediately and reliably, and the resin feeding must also be stopped to prevent the production of poor quality GFRP products.

FIG. 2 shows a cross section of the yarn breakage detector f&13 according to the invention, and FIG. 3 shows its side view. The yarn 6 coming out of the winding ball 15 is wound once around the pulley 1 of this device 13, and then
It is picked up by the chopper 12, cut, and sprayed. The pulley 1 is attached to a spindle 2, supported by a bearing 3 provided on a placket 4 fixed to an arm l1M of the robot, and rotates as the yarn 6 moves.

A rotating light shielding plate 5 is attached to the spindle 2, and holes 5a are provided in the rotating light shielding plate 5 at equal intervals on the circumference. This is not a hole; for example, as shown in FIG. 5, notches may be provided at equal intervals on the circumference.

In short, the shape does not matter as long as it blocks and transmits light rays regularly when rotated. Also, this hole or notch (
Hereinafter referred to as "slit". ) can be provided on the above-mentioned pulley 1, as shown in FIG. 4, and the rotating light shielding plate 5 can be omitted.

Beam switches having a light emitting part and a light receiving part are provided on both sides of the rotating light shielding plate 5 so that when the light shielding plate 5 rotates, light rays intermittently pass through the slits 5a. Reference numeral 8 denotes a beam switch electric wire and a lead wire for taking out an output signal.

The rotating parts of this thread breakage detection device, such as the boot I76 and the rotating light shielding plate 5, are formed to be as lightweight as possible and to have a small rotational inertia.

Next, the operation of this device will be explained. In FIG. 1, the yarn G passes from the winding bobbin 15 through the yarn guide 14, is applied once to the boot 176 of the yarn breakage detection device 13 according to the present invention provided at the base of the arm lla of the robot, and is then applied to the next yarn guide. 14' and taken over by the chopper 12, where it is cut and sprayed. At the same time, fluid resin is mixed and sprayed from a spray gun (not shown), and the GFRP
The product is manufactured.

Unless the composition ratio of glass fiber and resin is set at a constant value as determined in the design, the strength and other performance of the product will not be satisfied. However, during the above operations, if the supply of the yarn 6 is stopped due to clogging of the chopper 12 or breakage of the yarn 6, the composition of ingredients will be disrupted. In order to prevent this from happening, a thread breakage detection device 13 is provided to reliably detect when the thread is not being supplied, stop the supply of resin, keep the mixing ratio constant, and manufacture a good product as designed. be.

When the yarn 76 is normally fed, the pulley 1 is driven by the yarn 6 and rotates, and the light shielding plate 5 connected by the spindle 2 also rotates at the same speed. Then, the light beam from the beam switch 7 passes through the slit 5a and is blocked between the slits 5a. Therefore, the output signal of the beam switch has an intermittent waveform shown in zone A in FIG.

If the feeding of the yarn 6 is stopped, the rotation of the light shielding plate 5 is also stopped, and if the beam of the beam switch 7 is located at the slit 5a, it will become a signal of zone B in Fig. 6, and the beam will miss the slit 5a. At the position, the B' zone signal is output, and at the edge of the slit, the C zone signal is output, and both are continuous signals rather than the regularly intermittent signals of the A zone, so the yarn must not be fed immediately. is detected. In addition, the resistance of the yarn guide 14 and the chopper 1
If there is a slip etc. in step 2 and the yarn feeding speed changes, the pitch of the waveform will increase, so
If the normal intermittent waveform shown in the zone is stored in the microcomputer in advance, it can be automatically monitored. moreover,
The frequency of this intermittent waveform signal is proportional to the yarn feeding speed, so if this frequency is used as an input signal to control the blowout amount of the resin spray gun, the mixing ratio of glass fiber and resin can be controlled to be constant. can do.

In addition, in the case of glass fiber, the diameter of pulley 1 is 1 for yarn of normal thickness, considering the allowable bending radius of yarn.
6cm or more is desirable. In addition, in order to prevent inertia rotation of the pulley and stop the pulley immediately when the yarn is stopped, the pulley should be made of a tin plate or the like and the rotational inertia should be kept as small as possible.

The winding of the yarn 6 around the pulley 1 must be adjusted by adjusting the position of the yarn guide 14 so that the beginning and end of winding do not overlap in order to prevent the yarns from sliding or becoming entangled.

[Effects of the Invention] As described above in detail, according to the present invention, yarn breakage can be detected without any influence even if there is fuzzing of the yarn or vibrations caused by unwinding of the yarn. Therefore, it is particularly effective when applied when the device is subject to movement or vibration.

In addition, it is possible to reliably detect a break at any position in the thread, and even if the thread is not cut, for example, if the thread is jammed in a chopper, which could not be detected with conventional detection devices,
The detection device according to the present invention can reliably detect.

The thread feeding speed can also be detected by the frequency of the signal from the beam switch, and this signal can be used to control the amount of resin supplied from the spray gun. The mixing ratio of glass fiber and resin can be precisely set as designed, and the generation of inferior quality reinforced plastic can be prevented.

[Brief explanation of drawings]

Fig. 1 is a side view of a GFRP manufacturing robot, Fig. 2 is a sectional view of a thread breakage detection device according to the present invention, Fig. 3 is a front view thereof, and Fig. 4 is a sectional view of an embodiment using a pulley as a light shielding plate. , FIG. 5 is a front view of another embodiment of the slit, and FIG. 6 is a diagram showing beam switch signals. In the figure, l is a pulley, 5 is a rotating light shielding plate, 5a is a slit, 6 is a thread, 7 is a beam switch, 11 is a robot,
12 is a chopper, 13 is a thread breakage detection device, and 15 is a bobbin bobbin. Applicant Mitsubishi Heavy Industries Co., Ltd. Agent Patent Attorney Akira Sakama Patent Attorney Tsutomu Kitanishi Patent Attorney Ishikawa Shinpo Agent Patent Attorney Yoshimi Saigo Patent Attorney Yukio Harada No. 1 Figure 13 Figure 6 Figure 2 Figure 3tχ1 Article 41' Address 2-5-1 Marunouchi, Chiyoda-ku, Tokyo Name (6
20) Mitsubishi Heavy Industries, Ltd. Representative Satoshi Suenaga Part 4, Sub-Agent 105 1a 03-438-224
1 (Representative) Address: 3-4-17 Toranomon, Minato-ku, Tokyo
Number it! , ;I 40 5. Date of amendment order Voluntary 6 Subject of amendment 7. Contents of amendment (as per attached sheet 11 (2) Page 3 of the specification, lines 6-10 [Due to the movement of the thread...
. . . by a signal] is corrected to ``A rotary plate having a mark driven and rotated by the movement of the thread is provided, a non-contact sensor is provided to detect the mark, and by a signal from the sensor.'' (3) Add the following sentence after "Can be controlled." on page 8, line 3 of the specification. ``Furthermore, even if a disk having unevenness at equal intervals around the circumference is installed instead of the rotating light shielding plate 5, and a proximity switch is installed instead of the beam switch 7, the same effect as described above can be obtained. Attachment ``2. Claims: A yarn breakage detection device that is installed in a yarn feeding device to detect yarn breakage, is configured to be driven by the movement of the yarn and detect yarn breakage by the number of turns.'' A thread breakage detection device featuring

Claims (1)

[Claims] A yarn breakage detection device installed in a yarn sending device to detect yarn breakage includes a rotating plate having a slit that is driven and rotated by movement of the yarn, a beam switch configured to pass a light beam through the slit, and a beam switch configured to pass a light beam through the slit. A thread breakage detection device characterized in that the thread breakage detection device is configured to detect thread breakage based on a signal from a switch.