JPH05132234A - End breakage detector in sewing machine - Google Patents

Abstract

PURPOSE:To require no strong tension on thread, and enable any end breakage to be detected electrically in an easy manner as well as to make this detector utilizable for a sewing machine or the like so easily. CONSTITUTION:A light source 4 and a phototube light receiving part 5 receiving light irradiated out of this light source 4 are set up in the inner part of a detector body 1 provided with a guide groove 2 so as to make yarn Y travel a home position as being opposed to each other at both sides holding a yarn traveling part between, and a variation in a light receiving quantity in this light receiving part 5 is taken out as a pulse signal by a control part 8, thus it is installed so as to detect any end breakage, through which a motor is constituted so as to be stopped at the time of end breakage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a yarn breakage detecting device which can be suitably used mainly in industrial sewing machines, knitting machines, looms and the like.

[0002]

2. Description of the Related Art Conventionally, in industrial sewing machines and the like, it is necessary to immediately stop the operation of a machine when a yarn breakage occurs, and therefore a yarn breakage detection device is provided.

As a means for detecting the yarn breakage, conventionally, for example, a yarn to be fed is wound around a rotating piece once to run, and the rotation of the rotating piece accompanying the winding run of the thread is pulsed or the like. When the yarn breakage is detected by detecting the rotation stop of this top, the motor is stopped by a relay circuit or the like when the yarn breakage is detected, and the machine is stopped.

Further, a spring is used to actuate an action piece for actuating a relay circuit or the like elastically abutting the running yarn, and when the yarn breaks, the relay circuit is actuated to stop the motor. Some have been done.

In the former case, however, it is necessary to apply a certain tension to the yarn in order to wind the yarn around the top and rotate the top with frictional force. There is a drawback that it may break, and it cannot be used if the tension of the thread is weak.

Further, when the spring is used as in the latter case, friction occurs between the thread and the action piece, and it is necessary to apply tension to the thread against the spring force. It is apt to cause malfunctions and has a drawback that it cannot be used for yarns with a weak tension.

Further, in any of the above cases, there is a drawback that it is difficult to use in existing sewing machines and the like because of its structure, it occupies a certain space and the mounting location is limited.

Therefore, the present invention intends to provide a yarn breakage detecting device which can electrically and easily detect a yarn breakage without fear of causing the above problems and which can be easily attached to a sewing machine or the like for use. It is a thing.

[0009]

In the yarn breakage detecting device of the present invention which solves the above-mentioned problems, a yarn traveling portion is sandwiched by a detecting device main body which is provided with guide means so that the yarn travels at a predetermined position. A light source and a photoelectric tube light-receiving unit that receives light emitted from the light source are arranged on both sides of the light-receiving unit, and fluctuations in the amount of light received by the light-receiving unit are extracted as pulse signals to detect yarn breakage. It is characterized by.

[0010]

In the present invention described above, the yarn is guided by the guide means and travels between the light source and the photocell light receiving portion facing the light source. Then, the light emitted from the light source is received by the photoelectric tube light receiving portion facing the light source, and the amount of light received by this photoelectric tube light receiving portion depends on the yarn running, such as fine irregularities on the yarn surface or movement of fluff, or It fluctuates slightly due to vibrations and waviness of the running yarn. The fluctuation of the received light amount is taken out as an electric pulse signal, and the running state of the yarn and the yarn breakage are detected by the presence or absence of this pulse signal. That is, the yarn is running (the yarn is not broken) while the pulse signal is generated.

When the yarn breaks, however, the yarn does not exist between the light source and the photoelectric tube light-receiving portion, or the running of the yarn is stopped, so that fine irregularities on the yarn surface and movement of fluffs occur. Alternatively, vibration does not occur, fluctuations in the amount of light received by the photocell light receiving unit do not occur, and pulse signals cannot be extracted as described above, so that it is possible to detect that the yarn is not being fed, that is, the yarn is broken.

When the yarn breakage is detected in this way, an electric signal is sent to the control unit so that the operation can be controlled to be stopped.

[0013]

Embodiments of the present invention will now be described with reference to the drawings.

(1) shows the main body of the yarn breakage detecting device. As shown in the figure, a narrow U-shaped guide groove (2) in the detection device body (1) is provided in the yarn traveling direction as guide means for traveling the traveling yarn (Y) at a fixed position. It is provided at both ends. Further, the traveling yarn is provided outside the openings at both ends of the guide groove (2).
The holding members (3) and (3) for positioning and holding are arranged and adjusted so as to travel in contact with the bottom of the.

As the holding member (3), a wire is wound in a spiral shape as shown in the figure. The yarn (Y) is wound in the middle of the spiral so that the wire is wound in the center. It is convenient to pass through.

Further, inside the detection device body (1), the guide groove (2) and the holding member (3) sandwich the traveling portion of the yarn (Y) traveling at a certain position, and light is emitted to both sides thereof. A light source (4) made of an element and a photoelectric tube light receiving section (5) made of a light receiving element for receiving light emitted from the light source (4) are arranged to face each other, and the photoelectric tube detects a yarn breakage. It constitutes the device (6).

In the photocell device (6), the light emitted from the light source (4) is partially blocked by the yarn (Y) running between the photocell light receiving part (5) facing the light source (4), The amount of light received by the light receiving section (5) is reduced by the thickness of the thread (Y). Further, the amount of light received by the light receiving section (5) fluctuates as the yarn (Y) travels, as it repeatedly increases and decreases slightly due to fine irregularities on the yarn surface due to twisting of the yarn as shown in FIG. 3 and movement of the fluff.

The amount of received light is also caused by the vibration (Y) of the yarn itself caused by the traveling of the yarn (Y), or the yarn is wavy when it is fed from the winding bobbin as shown in FIG. And the yarn (Y) becomes the detector body (1).
Even when passing through the corrugated state as it is due to the distance between the guide grooves (2) and (2) and the thread tension, the amount of light received by the photocell light receiving unit (5) fluctuates so as to repeatedly increase and decrease. .. Especially, even if the yarn (Y) does not have fine irregularities or fluff, it varies.

Therefore, the fluctuation of the amount of received light is electrically taken out by a current and converted into a pulse signal by an electronic circuit of the control section (7) so that the running state of the yarn (Y), that is, the occurrence of yarn breakage occurs. Is configured to detect. If the yarn (Y) is thicker than the light emitted from the light source (4), the problem can be solved by replacing the light emitting element as the light source and the light receiving element of the light receiving section (5) with a larger one.

In the above construction, during normal traveling of the yarn (Y), the amount of light received by the light receiving section (5) fluctuates due to any of fine irregularities of the yarn, movement of fluff, or vibration of the yarn itself, This fluctuation is converted into a pulse signal by the electronic circuit of the control unit (7) and is taken out. While this pulse is being generated, the yarn (Y) is running (the yarn is not broken), so the current from the control unit (7) is passed through the relay to activate the relay circuit. The motor (8) is kept energized,
The yarn (Y) runs continuously.

When the yarn breakage occurs, the yarn (Y) does not exist between the light source (4) and the photoelectric tube light receiving unit (5), or the yarn breaks outside the detection device body (1). Then, the traveling of the yarn (Y) in the detection device body (1) is stopped.
Therefore, fine irregularities of the thread, movement of the fluff, or vibration of the thread itself do not occur, so that the amount of light received by the photocell light receiving unit (5) is constant and does not fluctuate, and no pulse is generated in the control unit (7). The state, that is, the occurrence of thread breakage is detected.

Therefore, the current flowing through the relay circuit or the like from the control section (7) is cut off to stop the energization of the motor (8) and stop the operation of the machine. As a result, yarn breakage can be detected easily and reliably, and the machine operation can be stopped immediately when the yarn breakage occurs.

The operation of a machine such as a sewing machine is started with a button switch or the like, and is controlled as described above after the running of the yarn is started.

When the thread breakage is detected as described above, it is not necessary to apply a strong tension to the thread as in the case of using a rotating piece or a spring, and the thread is not affected by a pulling force or friction as in the conventional case. There is no danger of breakage. Also thread (Y)
In the same manner as described above, yarn breakage can be detected even for those with low tension, and the performance of machines such as sewing machines can be fully brought out and high-speed operation becomes possible.

In the figure, (9) is a connector for connecting to the control section (7) and a power source, etc., and (10) is a mounting substrate.

The yarn breakage detecting device as described above may be arranged at any position as long as it is a traveling portion of the yarn fed and traveling in an industrial sewing machine, etc. It becomes possible to use it by attaching it to the device.

[0027]

As described above, according to the present invention, by utilizing the photoelectric tube device, the fine irregularities on the yarn surface and the movement of the fluff due to the traveling of the yarn, or the received light amount due to the vibration and the waviness of the yarn during traveling, By extracting the fluctuation as a pulse signal, thread breakage detection in a sewing machine etc. can be performed easily and reliably electrically, there is no need to apply strong tension to the thread, and the occurrence of thread breakage due to friction or tensile force can be prevented, and it is weak. It is also possible to detect a thread in tension. In addition, this yarn breakage detection device can be constructed compactly, and its attachment position may be any position from the yarn feeding part to the knitting part, and the attachment point is not limited, and it can be installed in an existing sewing machine device or the like. Is also easy. Furthermore, since it is not necessary to apply a strong tension to the yarn, it can be suitably used for a pile loom or knitting machine for towels and the like.

[Brief description of drawings]

FIG. 1 is a schematic view showing a first embodiment of the present invention.

FIG. 2 is a perspective view of a detection device body.

FIG. 3 is a sectional view taken along a guide groove.

FIG. 4 is an explanatory diagram showing a traveling state of another yarn.

[Explanation of symbols]

 (1) Detector main body (2) Guide groove (3) Holding member (4) Light source (5) Phototube receiver (6) Phototube device (7) Controller (8) Motor

Claims (1)

[Claims] 1. A photocell which receives light emitted from a light source and a light source, which face each other on both sides of a yarn traveling portion, in a detection device main body provided with guide means so that the yarn travels at a predetermined position. A yarn breakage detection device, which is provided with a light receiving part and is provided so as to detect a yarn breakage by extracting a variation in the amount of light received by the light receiving part as a pulse signal.