JPH0346575B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a weft yarn detection device in an air jet loom that utilizes an air jet to insert the weft, that is, to thread the weft through the shed.

[Prior art and its problems] In an air jet loom, the weft thread is made to fly through the shed by an air jet sprayed from a nozzle provided on one side of the shed.
Most of them use an air guide method that covers the weft flying part in a tunnel shape, or multiple air guides arranged along the shed, in order to prevent the jet airflow injected from the nozzle from spreading and decelerating to ensure weft insertion. A modified reed system with an auxiliary nozzle, or an air guide system with an auxiliary nozzle that is a combination of the above two methods is provided.

When inserting the weft, a weft filler provided on the side opposite to the yarn feeding side detects the arrival of the tip of the weft to confirm the insertion (for example, Japanese Patent Application Laid-Open No. 185843/1983). Usually, in addition to the filler that detects the arrival of the weft yarn, a second filler is provided at a certain distance in the weft flying direction to detect the weft yarn at the time of yarn breakage.

By the way, this is not so true in the case of the air guide method mentioned above, but especially in the case of the modified reed method with an auxiliary nozzle, the airflow from the auxiliary nozzle is injected in an oblique direction toward the guide groove of the modified reed, and a reflected flow is generated. In some cases, the jet airflow spreads more easily on the opposite yarn feeding side, and since the weft filler has a width in the front-rear direction, the jet airflow spreads out (a) as shown in Figures 6 and 7. A part of the weft yarn filler 10' collides with the side surface on the yarn feeding side, causing turbulence in the airflow. Therefore, due to the above-mentioned turbulence, the tip of the flying weft may be bent or distorted in front of the weft filler, causing trouble, and the weft filler may not be able to detect the weft.

In view of the above, it is an object of the present invention to provide a weft detection device that prevents turbulence in the weft filler portion provided on the opposite yarn feeding side of an air jet loom, and eliminates the risk of defective weft detection during weft insertion. It is.

[Means for Solving the Problems] That is, the present invention is a weft yarn detection device for an air jet loom in which the jet airflow causes the weft yarns to fly and pass through the shed, and particularly solves the above-mentioned problems. In order to solve this problem, a first weft filler that detects the arrival of the weft tip when inserting the weft and a second filler that detects the cut weft when the yarn breaks are provided outside the selvedge on the anti-yarn feeding side. , on the side of the first weft filler facing the jet airflow, protruding in the direction opposite to the airflow direction, and on both sides of the side facing the weft flying portion and the back side thereof, respectively, on the main body side of the filler. A guide recess that gradually becomes shallower and narrower is formed, and a jet airflow rectification guide is provided which has a thinner wall shape toward the tip facing the airflow, so as to rectify the airflow from the side of the filler. It is something.

[Function] According to the weft yarn detection device of the present invention described above, during weft insertion, the jet airflow generated by the main nozzle and the auxiliary nozzles that cause the weft to fly spreads on the yarn feeding side, and a part of the jet airflow is transmitted to the first weft yarn. However, since a jet airflow rectifying guide is provided on the side of the weft filler opposite to the jet airflow, this restricts the spread of the airflow and prevents the jet airflow from colliding with the side of the filler. The jet airflow is guided to the detection side of the filler main body along the guide recess on the surface opposite to the weft flying part of the rectifying guide, so that the jet air flow is directed to the filler main body without causing turbulence due to collision with the weft filler. The flow will definitely flow in front of the detection side.

Moreover, the rectifying guide has a similar guide recess formed on the back side, and is thinner toward the tip facing the airflow, so the airflow that hits the tip of the rectifying guide is directed toward the side facing the weft flying part. The airflow flowing outward from the tip to the back side is rectified by the guide recess on the back side and flows smoothly without colliding with the weft filler. There is also no possibility that turbulent airflow such as vortices will occur on the sides and affect the airflow in the weft flying portion.

Therefore, the tips of the weft yarns flown by the jet airflow are reliably held in the airflow without being bent or distorted, and can be reliably detected by the weft filler.

[Example] Next, embodiments of the present invention will be described based on the drawings.

1 to 5 show an embodiment of the present invention, in which 1 is a warp, 2 is a woven fabric, 3 is a reed, and 4 is a reed frame. It consists of a modified reed having a protrusion that forms a guide groove 5 for weft flying. 6 is a main nozzle, and this main nozzle 6 is a drum type weft storage device 7 as shown in the figure.
It is provided so that the weft yarn 8, which is fed through the feeder, etc., is allowed to fly and pass through the shed (A).

Auxiliary nozzles 9 are arranged at required intervals along the shed (A) and are provided to assist the main nozzle 6 in causing the weft to fly.

The pressurized air for the jet air flow of the main nozzle 6 and the auxiliary nozzle 9 is supplied from a pressure source such as a compressor through a solenoid valve, a pressure regulator, etc. in a feeding path so as to perform a predetermined injection action, as is known in the art. is supplied and controlled.

Reference numeral 10 denotes a first weft filler made of a photoelectric tube or the like provided outside the selvedge portion on the side opposite to the side where the weft is fed by the main nozzle 6, that is, on the anti-yam feeding side. The arrival of the yarn 8' is electrically detected by the weft filler 10, and this detection signal is input from a detection circuit to a control section (not shown) to control the operation of the loom.

As shown enlarged in FIG. 1 and FIGS. 3 to 5, the weft filler 10 has a side portion opposite to the jet airflow direction, which guides the airflow from the side of the filler to the front side of the filler main body. A rectifying guide 11 for the jet airflow is provided to protrude in a direction opposite to the airflow direction. The rectifying guide 11 has upper and lower surfaces approximately the same width as the filler main body 12, and has a guide recess 13 that becomes gradually shallower and narrower toward the filler main body 12, at least on the side facing the weft flying portion, to direct the jet airflow. It is formed so that it can be guided to the front side of the filler main body 12 while controlling its spread. Furthermore, as shown in the figure, rectification guide 1
1, a corresponding guide recess 14 is formed on the opposite side to the guide recess 13, that is, on the back side,
The distal end side facing the airflow is formed into a thinner streamline shape, so that the airflow rectification effect and the prevention of turbulence are more reliably performed.

The above-mentioned rectifying guide 11 is not limited to the one having the above-mentioned shape. For example, the rectifying guide 11 may be formed by bending a thin plate into a gutter shape so as to form a guide recess and attaching this to the side surface of the weft filler 10. As long as it can function, it can be implemented in the same manner as above.

Reference numeral 15 denotes a second filler for detecting yarn breakage, which is provided at a distance to the side of the weft filler 10, and the tip of the weft that has been inserted normally is connected to the second filler 15 and the weft filler. This second filler 15 is designed to be located between the second filler 15 and the second filler 15, and the cut weft yarn that is blown away due to yarn breakage is transferred to the second filler 15.
is arranged to detect thread breakage and send a signal to the control unit.

Although not shown, the weft filler 1
A means for maintaining the weft tension, such as a yarn end suction means, is provided slightly to the side of the weft yarn.

To explain the operating state of the above-mentioned device, the weft yarn 8 is flown by the jet airflow from the main nozzle 6 and the auxiliary nozzle 9 and passed through the shed (A), and the tip end 8' of the weft yarn 8 reaches the shed. is detected by the weft filler 10, and completion of weft insertion is confirmed.

Therefore, the jet airflow that causes the weft to fly spreads on the yarn feeding side and a part of it tries to collide with the side of the weft filler 10. Since the rectifying guide 11 is provided, this restricts the spread of the airflow, and the airflow from the side of the filler is directed along the guide recess 13 formed on the surface of the rectifying guide 11 facing the weft flying portion. The jet airflow is guided to the detection side of the filler main body 12, so that most of the jet airflow is directed to the filler main body 1 without causing turbulence due to collision with the weft filler 10.
It will surely flow in front of the detection side of No. 2.

In addition, since the tip of the straightening guide 11 has a thin shape, the airflow that hits this tip is easily divided into the side facing the weft flying portion and the back side thereof, and moreover escapes to the back side of the straightening guide 11. The airflow is rectified by the guide recess 14 on the back surface side and flows smoothly without colliding with the weft filler 10, and turbulence such as eddies may occur on the back surface side of the rectification guide 11, causing the weft yarn to fly. There is no risk of affecting airflow.

Therefore, the tip 8' of the weft yarn 8 which is flown by the jet airflow is not bent or distorted, and is reliably held at a predetermined weft flying position by the jet airflow, and is reliably held by the weft filler 10. This means that it can be detected.

In the above embodiment, a modified reed type air jet loom with an auxiliary nozzle is shown, but the weft detection device of the present invention can also be used in an air guide type loom that covers the weft flying part in front of the reed in a tunnel shape. This can be carried out in the same manner, and in this case as well, disturbances in the airflow discharged from the air guide can be prevented and weft yarn detection can be performed reliably.

[Effects of the Invention] As described above, according to the weft detection device of the present invention, turbulence due to collision of jet airflow with the weft filler does not occur due to the rectification effect of the rectification guide provided on the side of the first weft filler. In addition, there is no turbulence in the airflow flowing outward on the back side of the rectifying guide, which prevents bending or distortion of the weft tip that is flown by the jet airflow, and the arrival of the weft can be accurately detected and weft insertion can be carried out. This can be confirmed without error, and it is possible to eliminate the stoppage of the loom due to poor weft detection, thereby improving weaving efficiency.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a weft filler showing an embodiment of the present invention, Fig. 2 is a perspective view of the main part of an air jet loom equipped with the weft filler, Fig. 3 is an enlarged plan view of the same part, and Fig. 4 is the same part. 5 is a side view in the direction of the arrow in the previous figure, FIG. 6 is a plan view of a conventional weft filler portion, and FIG. 7 is a side view in the direction of the arrow in the figure. (A)...Shed road, 3...Reed, 3a...Reed feather, 6...
Main nozzle, 8...Weft, 8'...Weft tip,
9...Auxiliary nozzle, 10...Weft filler, 11
... Rectification guide, 12 ... Filler main body, 13 ...
...Guide recess.

Claims (1)

[Claims] 1. In an air jet loom in which the jet airflow causes the weft to fly and pass through the shed, a first loom is installed outside the selvedge on the opposite yarn feeding side to detect the arrival of the weft tip during weft insertion. a weft filler, and a second filler for detecting a cut weft at the time of yarn breakage, and a side portion of the first weft filler facing the jet airflow protrudes in a direction opposite to the airflow direction, and a weft Guide recesses are formed on both the side facing the flying part and the back side thereof, each of which becomes shallower and narrower toward the main body of the filler, and a rectifying guide for the jet airflow is provided which has a thinner wall shape toward the tip facing the airflow. 1. A weft yarn detection device for an air jet loom, characterized in that the weft yarn detection device is configured to rectify airflow from the sides of a filler.