JPS5922812B2 - Weft insertion method on shuttleless loom - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a weft insertion method in a shuttleless loom in which a jet of compressed air or the like is used to fly the weft yarn into a shed.

The conventional so-called air jet loom is of a type in which an air current is applied to the weft threads to fly them into a shed, thereby inserting the weft threads between the upper and lower warp threads.

However, if an air injection nozzle is simply provided at the end of the shed, the speed of the air coming out of the nozzle will decrease rapidly due to the diffusion of the injected air, and as a result, the speed at the weft tip will slow down, resulting in a wide width. In some cases, it is difficult to insert the weft, and because the yarn from the rear is faster than the yarn at the tip, the tip is pushed up from the rear, causing the tip to bend and cause snarls after weft insertion.

In addition, the force that acts on the weft is only the frictional force that acts between the weft and the air flow, which is a small force, which causes a disadvantage.Due to the diffusion of air, there appears to be considerable variation in the weft flight path, resulting in a stable weft. The disadvantages were that the weft was not inserted properly, and that the tip of the weft yarn got caught in the warp group or hit the lead due to the diffusion phenomenon, leading to errors in weft insertion.

Therefore, in order to eliminate these drawbacks, the following measures have been conventionally taken.

In other words, an air guide is installed inside the shed to prevent air from dispersing, or a reed for beating the reed is deformed to form a shed guide.
Installing an appropriate number of auxiliary nozzles in the middle of the shed is a measure to prevent the flow velocity in the shed from decreasing and to stabilize the flight of the weft yarn.

However, by taking these measures, new inconveniences arose, and a satisfactory shuttleless loom could not be obtained.

Therefore, an object of the present invention is to provide a weft insertion method that solves the above-mentioned problems of conventional shuttleless looms and does not introduce any new drawbacks.

Considering this purpose, the present invention attaches a droplet to the tip of the weft yarn, freezes the droplet at low temperature, and then flies the frozen droplet together with the tip of the weft into the shed using a jet of compressed air or the like. The present invention resides in a weft insertion method for a shuttleless loom, which is characterized by:

Other objects and advantages of the invention will become more readily apparent from the following description of a preferred embodiment, illustrated in the accompanying drawings.

FIG. 1 is an explanatory diagram showing the entire apparatus for carrying out the weft insertion method according to the present invention.

Briefly explaining this weft inserting device, the tip of the weft W from the weft cone 1 is located at a droplet freezing section generally indicated by the symbol A, and droplets are attached thereto as will be described later. The drops are frozen.

Therefore, in the following description, this frozen droplet will be referred to as an ice bullet.

Although the droplets can be made of any liquid that freezes relatively easily, water is preferred.

This ice bullet 2 is fired by compressed air, passes through an accelerating tube 3, flies within the opening of the warp T, and weft insertion is thus performed.

The droplet freezing section A is supplied with liquid from the water storage section B through the liquid transfer section C.

Next, the above-mentioned weft insertion device will be explained in more detail.

A length measuring drum 4 rotatably supported by a part of the machine base is pressed against the circumferential surface of a rotating roller 5 by a spring 6.

The rotating roller 5 is connected to a suitable drive device (
(not shown) and is constantly rotated.

Therefore, the length measuring drum 4 is also constantly rotated by the rotary roller 5 to measure the length of the weft from the weft cone 1.

A weft tension adjustment device 9 is provided in front of the length measuring drum 4, and a storage device 10 for pooling a predetermined amount of wefts is provided behind the length measuring drum 4.

Therefore, the weft yarn W from the weft cone 1 reaches the storage device 10 via the guide 11, the tension adjustment device 9 and the guide 12.

The storage device 10 is provided with openings at the top and bottom, and air normally passes through these openings as shown by the arrows, causing the weft W passing through the storage device 10 from the left side to the right side to loosen as shown by the dotted line. .

Immediately before weft insertion, a predetermined amount of weft yarn W is pooled in the storage device 10.

A weft braking device 13 and a weft pulling device 14 are arranged behind the storage device 10.

The weft pulling device 14 is composed of a guide roller 15, a vertically movable pin 16, etc., and as described later, the tip of the weft W cut by a cutter 17 located near the exit of the acceleration tube 3 is pulled into a droplet. This is for pulling back the weft yarn W to a predetermined position in the frozen section A. During pulling back, the pins 16 move away from each other as shown by chain lines, and the weft braking device 13 holds the weft W by its pair of pressers during pulling back. Brake between the plates.

Behind the weft pulling device 14, a droplet freezing section A is arranged which also fires ice bullets using compressed air.

The droplet freezing section A includes a freezing chamber and a firing chamber, which will be described later, and a housing 18 for the same, and the housing 18 is provided with a compressed air inflow hole 20 that selectively communicates with the firing chamber.

Compressed air is supplied to the firing chamber in the droplet freezing section A by the compressor 2.
2.

The compressor 22 has a piston 23, which is driven by a suitable drive device (not shown) via a crankshaft 24 and a freezing rod 25.

The air compressed by the compressor 22 is transferred to a compressed air pump 26.
and is selectively supplied into the housing 18 from the inflow hole 20 via the passage 27.

When compressed air is supplied, pressure is applied to the ice bullet in the firing chamber for firing.

The droplet freezing section includes an elongated cylindrical hollow acceleration tube 3 extending toward the opening of the warp threads T.

A known cutter 17 for cutting the weft W after weft insertion is arranged near the tip of the accelerating tube.

The structure and operation of the droplet freezing section A included in the weft insertion apparatus of the present invention will be explained in detail later.

Therefore, from the above explanation, the water from the water storage part B is transferred to the water transfer part C.
The ice pellets are supplied to the droplet freezing section A through the freezing chamber (here, the droplets are attached to the tip of the weft and frozen, and the frozen droplets, that is, the ice bullets, are sent to the firing chamber, where they are fired by compressed air. It can be seen that the threads pass through the acceleration tube 3 and through the opening of the warp threads T.

29 is a woven fabric.

Next, the ice bullet 2 that has passed through the opening of the warp T as described above
are processed by ice bomb processing equipment.

This ice bullet processing device includes, for example, an L-shaped ice bullet melting table 30 disposed opposite to the acceleration tube 3 while sandwiching the warp threads T.

A heater 31 capable of melting flying ice bullets 2 is provided in a vertical extension of the melting table 30.

Further, above the melting table 30, there is a hot air blowing nozzle 32 that sends hot air by appropriate means to help melt the ice bullets.

A water tank 33 located below the melting table 30 receives melted cold water, and the cold water is injected into the water storage part B by a water pump 34.

In this way, by effectively utilizing the phase change of water, water droplets can be turned into ice bullets at a relatively low cost.

Next, the structure and operation of the droplet freezing section A will be explained with reference to FIGS. 2a to 2C.

In FIGS. 2a-c, the housing 18 of the droplet freezing section A
has a generally cylindrical freezing chamber 35 and a firing chamber 36 formed at the outlet end of a pair of inflow holes 20 connected to the acceleration tube 3 while being curved in a roughly J shape.

The freezing chamber 35 is surrounded by conventional ultra-freezing means 37 or an ultra-low temperature material such as liquid oxygen, liquid nitrogen, etc., and the ultra-freezing means 37 is surrounded by a suitable heat insulating material 38.

One end of the freezing chamber 35 is open to the outside to allow entry of the weft nozzle 39 and water nozzle 40 arranged concentrically, and the other end serves as a stopper to stop these nozzles 39 and 40 at a predetermined position. It is tapered to allow for

The water nozzle 40 defines an annular passage 41 which is in fluid communication with the water conveying section C.

In FIG. 2a, water passing through the annular passage 41 as indicated by the arrows collects at the tip of the nozzle assembly 39 and 40 and forms a droplet 2a surrounding the tip of the weft W.

While the assembly advances through a freezing chamber 35 surrounded by super-freezing means 37 towards a firing chamber 36 as indicated by the arrow in FIG.
The droplet 2a gradually freezes and becomes Japan 2.

When the distal end of the assembly engages with the tapered part of the freezing chamber 35 as shown in FIG. It is fired by the air, flies along a predetermined path together with the weft yarn W, and inserts the weft.

At this time, the heat of the compressed air flow will melt any frozen water at the tip of the nozzle, and it will be moved to the position shown in Figure 2a by shearing.

As described above, the weft insertion method of the present invention can be carried out with a device having very few moving parts, so the process is simplified, and the device is quite simple.

In addition, the weft is not accelerated solely by the friction between the weft and the air, but is accelerated by the force exerted on the surface of the weft, making it possible to run the weft at a higher speed and increasing the average weft insertion speed.

Furthermore, since mass is added to the tip of the weft yarn, stable weft insertion is expected without causing a fluff phenomenon at the tip of the weft yarn during flying.

In addition, the mass added to the weft tip has an inertial force when accelerated at high speed, so the stable flight distance of the weft becomes longer.
Even if the air speed decelerates, the domestic speed does not suddenly decrease, and the tip pulls the yarn coming from the rear, so weft insertion errors do not occur.

Therefore, the present invention provides a weft insertion method that solves the problems of conventional shuttleless looms and does not introduce any new drawbacks.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an apparatus for carrying out the weft insertion method of the present invention, and FIGS. 2a and 2c are cutaway views illustrating the structure and operation of the droplet freezing section of the weft insertion apparatus of FIG. 1. 2...Frozen droplet, 2a...Droplet, W.
...weft.

Claims (1)

[Claims] 1. In a shuttleless loom characterized by attaching a droplet to the tip of a weft yarn, freezing the droplet at a low temperature, and then making the frozen droplet fly together with the tip of the weft yarn into a shed by a jet of compressed air or the like. Weft insertion method.