KR20010014563A - Weft-insertion nozzle of water jet loom - Google Patents

Abstract

PURPOSE: To provide a weft insertion nozzle capable of improving weft insertion rate without increasing the consumption of a power and while keeping the stability of the weft insertion and appearance quality of a textile. CONSTITUTION: A weft yarn Y piercing a needle 14 for guiding the weft yarn Y is inserted with a pressurized water jetted from a jetting opening 29 by the supply of the pressurized water to a waterway 18 between the outer periphery of the needle 14 for guiding the weft yarn and the inner hole 122 of a nozzle body 12. Plural distributors 192 are arranged in a ring like shape in the waterway 18. A contracted passage 173 is formed at the downstream of the plural distributors 192. The angle θ of the tapered hole 171 for forming-the contracted passage 173 is regulated within the range of 15deg.-30deg., and the length L of the distributor 192 in the conveying direction of the weft yarn Y in the needle 14 for guiding the yarn Y is regulated within the range of 0.71-1.71 times (5-12 mm) as much as the diameter d of the inner hole 122.

Description

Weft-insert nozzle for water spray looms {WEFT-INSERTION NOZZLE OF WATER JET LOOM}

The present invention forms a water channel between the outer circumferential surface of the weft guide needle (neddle) inserted into the nozzle body and the inner circumferential surface of the nozzle body, and by supplying pressure water to the water channel to inject the pressure water from the injection port for the weft guide needle It relates to a weft insertion nozzle for weft inserting the weft passed through the with the injection water injected from the injection port.

In the weft insertion nozzles disclosed in Japanese Patent Application Laid-Open No. Hei 4-18053, Japanese Patent Application Laid-Open No. 62-88779, and Japanese Patent Application Laid-open No. Hei 10-130997, the flow of pressure water in the weft insertion nozzle is rectified. A rectifying means is provided for increasing the injection speed of the weft inserting water while ensuring the focusing property of the jetting water injected from the weft inserting nozzle. The rectifying means comprises a plurality of stabilizers arranged in an annular channel around the weft guide needle. The pressure water flowing in the weft inserting nozzle is rectified through the plurality of commutators. The rectified pressure water is injected from the injection port of the weft insertion nozzle, attracts the weft thread passing through the weft guide needle, and squeezes the inside of the inclined opening.

Conventionally, when the weaving width is about 190 cm, the loom rotation speed is about 800 rpm. In recent years, when the weaving width is about 190 cm, it is required to increase the loom rotation speed to about 1050 rpm to about 1300 rpm. In other words, in the past, weft insertion rates at which wefts are inserted at a rate of 1500 m / min are conventional, but recently, weft insertion rates at which wefts are inserted at a rate of 2000 m / min to 2500 m / min have been required. In order to increase the weft insertion rate, the injection speed of the weft insertion water must be increased, and in order to increase the injection speed, the supply pressure of the pump for pumping water to the weft insertion nozzle can be increased. Generally, the spring force is used for pumping water by a pump, and what is necessary is just to increase the said spring force in order to raise supply pressure. However, when the spring force is increased, the energy for bending the spring increases, and it is not desirable to increase the supply pressure of the pump in terms of energy saving.

In addition, when the injection speed of the weft inserting water is increased, if the turbulent components remain without being sufficiently rectified between the commutators in the weft inserting nozzles, the diffusion speed may increase because the injection speed is increased. As diffusion increases, the number of collisions with the warp increases, the warp lint increases, and the quality of the cloth decreases, or the amount of shaking of the warp tip ends up, resulting in a weft insertion failure.

It is an object of the present invention to provide a weft insertion nozzle which can improve the weft insertion rate while ensuring the weft insertion stability and quality of the article without bringing an increase in power consumption.

1 is a side sectional view showing a first embodiment.

2 is a cross-sectional view taken along the line A-A of FIG.

3 is a perspective view of the rectifying means.

4 is a graph in which the water collection rate is measured by changing the angle θ of the tapered hole 171 and the length L of the commutator 192.

5 is a graph evaluating the weft insertion stability by changing the angle θ of the taper hole 171 and the length L of the commutator 192.

6 is a graph evaluating fabric quality by changing the angle θ and the length L. FIG.

7 is a schematic side view showing a device for measuring collection rates.

8 is a schematic side view showing a weft insertion nozzle;

9 is a side cross-sectional view showing a second embodiment.

* Brief description of the main parts of the drawing *

10: weft insertion nozzle 12: nozzle body

122: internal space 14: needle for weft guide

171: taper ball 173: narrowing flow path

18: channel 19: rectification means

192: commutator 20: injection hole

Y: weft

Therefore, in the present invention, a water channel is formed between the outer circumferential surface of the weft guiding needle inserted into the nozzle body and the inner circumferential surface of the nozzle body, and the pressure water is injected from the injection port by supplying the pressure water to the water path to the weft guiding needle. Rectifying means for weft inserting nozzle for weft inserting the weft which has passed together with the sprayed water, and rectifying means formed by arranging a plurality of commutators in said waterway around said weft guide needle in an annular manner, and downstream of said plurality of commutators. And a weft inserting nozzle having a narrowing flow path formed between the inner circumferential surface of the taper hole and the outer circumferential surface of the weft guiding needle, the diameter of which decreases as it goes from the commutator side toward the ejection opening. The angle of the taper hole in the range of 15 ° to 30 °, and at the same time in the weft guide needle The length of the commutator in the weft conveyance direction of was in the range of 0.71 times to 1.71 times the inner diameter of the nozzle body.

As disclosed in Japanese Patent Application Laid-open No. Hei 4-18053, the angle of the conventional taper hole (indicated by θ in the specification and drawings of Japanese Patent Application Laid-open No. Hei 4-18053) is about 6 ° to 11 °. At this angle of taper hole, the pressure loss is large, and the weft insertion rate is about 1500 m / min. A configuration in which the angle of the taper hole is 15 ° to 30 ° and the length of the commutator is 0.71 times to 1.71 times the diameter of the nozzle body inner hole results in a weft insertion rate of about 2000 m / min to 2500 m / min.

In the invention of claim 2, the angle of the taper hole is in the range of 15 ° to 30 °, and the length of the commutator in the weft feed direction in the weft threading guide is set to 5 mm to 12 mm.

The diameter of the nozzle body inner hole in a general weft insertion nozzle is about 7-8 mm. The configuration in which the length of the commutator is 5 mm to 12 mm is suitable for application to the general weft insertion nozzle.

Embodiment of invention

EMBODIMENT OF THE INVENTION Hereinafter, 1st Embodiment which actualized this invention is described based on FIG.

1 shows the weft insertion nozzle 10. The cylindrical nozzle body 12 is fitted in the support hole 111 of the holder 11. The cap 13 is screwed to the outer peripheral surface of the front end side (right side in FIG. 1) of the nozzle main body 12. As shown in FIG. The holder 11 is fitted by tightening the cap 13 between the flange portion 121 and the cap 13 formed on the rear end side (left in FIG. 1) of the nozzle body 12 and fixedly mounted to the holder 11. have. The support hole 111 around the nozzle body 12 is connected to the water supply passage 112 in the holder 11, and the annular chamber 16 between the outer circumferential surface of the nozzle body 12 and the support hole 111 is the water supply passage. Connected to (112).

The weft guide needle 14 is fitted in the cylinder of the nozzle main body 12. The cap 15 is press-fitted to the rear end of the weft guiding needle 14. The cap 15, which is a part of the weft guide needle 14, is screwed to the inner circumference of the flange portion 121, and the large diameter portion 141 of the weft guide needle 14 is the internal hole of the nozzle body 12. It is fitted to the (122). An annular channel 18 between the small diameter portion 142 of the weft thread guide needle 14 and the inner circumferential surface of the inner hole 122 of the nozzle body 12 is connected to the annular chamber 16 through the inlet 123. The inlet 123 is formed at equal intervals on the nozzle body 12 around the small diameter portion 142 of the needle 14 for weaving thread. The outer circumferential surface of the small diameter portion 142 is slightly tapered.

In the cylinder of the tip part of the nozzle main body 12, the cylindrical injection port formation body 17 is press-fitted and fixed. A taper hole 171 is formed in the inner circumferential surface of the injection port forming body 17 serving as a part of the nozzle body 12. The taper hole 171 has a shape in which the diameter decreases from the rear end of the injection hole forming body 17 toward the tip end, and the range of the taper hole 171 is the rear end of the injection hole forming body 17 from the rear end of the injection hole forming body 17. And step 172 between the ends. The tip-side small diameter portion 142 of the weft thread guide needle 14 is inserted into the injection port forming member 17 so as to pass through the inside of the tapered hole 171 to reach the step 172. Between the inner circumferential surface of the taper hole 171 and the outer circumferential surface of the small diameter part 142 becomes a flow path 173 narrowing. The tip of the narrowing flow path 173 serves as the injection port 20.

A rectifying means 19 is formed in the annular channel 18. As shown in FIG. 3, the rectifying means 19 includes a ring portion 191 press-fitted into the inner hole 122 of the nozzle body 12, and a plurality of commutators 192 formed at equal intervals in an annular manner on the inner circumference of the ring portion 191. ) (20 in the present embodiment).

The pressure water supplied from the pump (not shown) flows into the waterway 18 via the water supply passage 112, the annular chamber 16, and the inlet 123. The pressure water flowing into the channel 18 is injected from the injection port 20 through the plurality of commutators 192 and through the narrowing flow path 173. The weft yarn Y passed in the weft guide needle 14 is weft inserted into the inclined opening by water injection from the injection port 20.

In the present embodiment, the outer diameter D (shown in FIG. 1) of the nozzle body 12 is 12 mm, and the diameter d (shown in FIG. 1) of the inner hole 122 is 7 mm. The diameter d is measured on the upstream side of the commutator 192. In the present invention, the length L (shown in FIG. 1) of the commutator 192 is the average length in the conveying direction (direction indicated by the arrow R in FIG. 1) of the weft yarn Y in the weft yarn guide needle 14. Shall be.

4, 5 and 6 show the angle θ of the taper hole 171 and the length L of the commutator 192 in terms of water concentrating property, weft insertion stability, and fabric quality of water injected from the weft insertion nozzle 10. ) Is a graph showing the results of weaving experiments to determine the appropriate range. The weaving conditions in this case are made into a loom rotation speed of 1200 rpm, a straight width of 190 cm, and a supply pressure (pump pressure) to the water supply passage 112 of 100 kgf / cm 2. The woven fabric is a nylon taffeta.

The graph of FIG. 4 shows the collection rate (%) when the angle (theta) of the taper hole 171 and the length L of the commutator 192 are variously changed. As for the collection rate, the axis center of the inclination guide needle 14 is located in the 1/2 position of the angle (alpha) which the up-down inclination T shown in FIG. A collecting pipe 21 having a diameter of 7 mm provided coaxially with the axis of the weft guiding needle 14 at a position 190 cm away from the weft insertion end side with respect to the installation position of the weft insertion nozzle 10 (shown in FIG. 7). The ratio of the quantity of water collected in the inside) and the total amount of water injected from the weft insertion nozzle 10 is shown. 7 and 8 are schematic side views of the collecting pipe 21 and the weft inserting nozzle 10 as viewed from the side of the inclined row, respectively, reference numeral 22 denotes a heald, 23 a reed, T a warp and a woven fabric. Indicates. The horizontal axis of the graph of FIG. 4 shows the angle (theta) of the taper hole 171, and a vertical axis shows a collection rate. Curve D is a collection rate curve when the length L of the commutator 192 is 3 mm (prior art). Curve E1 is a collection rate curve when the length L of the commutator 192 is 5 mm, and curve E2 is a collection rate curve when the length L of the commutator 192 is 6 mm. Curve E3 is a collection rate curve when the length L of the commutator 192 is 9 mm, and curve E4 is a collection rate curve when the length L of the commutator 192 is 12 mm. Curve E5 is a collection rate curve when the length L of the commutator 192 is 15 mm.

The graph of FIG. 5 is based on the amount of shaking of the weft tip of the non-period just before reaching the weft insertion end when the angle θ of the taper hole 171 and the length L of the commutator 192 are varied. Indicates an evaluation. In the graph of FIG. 5, the horizontal axis represents the angle θ of the tapered hole 171, and the vertical axis represents the length L of the commutator 192. The mark indicates a case where the shake amount is less than 3 mm, the mark Δ indicates a case where the shake amount is 3 mm or more and less than 5 mm, and the x mark indicates a case where the shake amount is 5 mm or more. The amount of shaking 3 mm or more and less than 5 mm is the minimum condition for ensuring the weft insertion.

The graph of FIG. 6 shows the fabric quality when the angle (theta) of the taper 171 and the length L of the commutator 192 are variously changed. In the graph of FIG. 6, the horizontal axis represents the angle θ of the tapered hole 171, and the vertical axis represents the length L of the commutator 192. Indicated is A half,? Indicates B half, and × indicates C half. The determination of the quality of the cloth is carried out on the basis of the number of fluff and cartilage. Particularly, fluff and cartilage during high-speed weaving are caused by the water sprayed from the weft insertion nozzle 10 colliding with the inclination T.

In the conventional weft insertion nozzle having the angle θ of the taper 171 at about 6 ° to 11 °, the narrowing flow path 173 formed between the inner circumferential surface of the taper hole 171 and the outer circumferential surface of the weft guide needle 14 is provided. In this case, the portion of the passage cross-sectional area that is as small as the passage cross-sectional area of the injection port 20 is lengthened in the weft yarn Y conveying direction R in the weft yarn guide needle 14. As a result, the flow path resistance increases and the pressure loss increases, and the weft insertion rate is about 1500 m / min. If the angle θ of the taper 171 is larger than the conventional one and is 15 ° or more, the portion of the passage cross-sectional area which is as small as the passage cross-sectional area of the injection hole 20 is shorter than the conventional one, so that the flow path resistance is reduced and the pressure loss is reduced It can be confirmed that the injection speed is increased to obtain a weft insertion rate of 2000 m / min to about 2500 m / min.

However, simply increasing the angle θ of the taper hole 171 lowers the concentration of jetting water and causes problems in weft insertability and fabric quality. That is, it is difficult to arrange the plurality of inlets 123 in a symmetrical manner with respect to the water supply passage 112, and thus, a time difference occurs in introducing the pressure water into the plurality of inlets 123. When such a time difference occurs, turbulence including the swirl component in the pressure water in the channel 18 occurs. There is a sufficient gap between the commutators 192 to reduce the flow resistance, so that the turning component remains slightly even after the pressure water passes between the commutators 192. The turning component remaining after passing between the commutators 192 acts as a centrifugal force with respect to the injection water, and this action is considered to be one cause of the diffusion of the injection water. Diffused jetting water collides with the slope, increasing fluff and hard roots and degrading the quality of fabric. In addition, the weft conveyance force decreases or the nonuniformity in the weft non-circumferential direction increases, so that weft insertion defects occur a lot. It is known that the water collection rate required for reliable weft insertion is about 15%.

Although not shown in the graph of FIG. 4, it is as above-mentioned that angle (theta) of the taper hole 171 should be 15 degrees or more in order to obtain the weft insertion rate 2000m / min-about 2500m / min.

As shown in FIG. 4, according to the experimental result of the conventional rectification means shown by the curve (D), a collection rate is less than 15% at 15 degrees or more, and a collection rate falls as angle (theta) becomes large. According to the experimental results of the rectifying means 19 whose length L of the commutator 192 is 5 mm-12 mm, in the range whose angle (theta) is 15 degrees-30 degrees, a collection ratio is 15% or more, but the angle ( When (theta)) is 30 degrees, a collection ratio will be a value which slightly exceeds 15%. Although not shown, if the angle θ exceeds 30 °, the collection rate is further lowered, and reliable weft insertion cannot be expected regardless of the length L of the commutator 192.

When the length L of the commutator 192 is 15 mm, when the angle (theta) is 25 degrees, a collection ratio will fall to 11%. It is considered that the cause of such a low water collection rate is that when the length L of the commutator 192 is 15 mm, the commutation effect is the highest among commutators whose length is 15 mm or less, while the flow path resistance is large. The large flow path resistance causes a large pressure loss and a sufficient flow rate cannot be obtained. Therefore, the weft inserting performance is deteriorated, and reliable weft insertion cannot be expected.

In order to achieve the weft insertion rate 2000 m / min to 2500 m / min without raising the pump pressure, the angle θ of the taper hole 171 is 15 ° or more as described above, but In yield experiments, up to 30% is the upper limit for weft insertion. That is, the result that what is necessary is just to set the angle (theta) of the taper hole 171 to 15 degrees-30 degrees.

In the experiment of weft insertion stability shown in FIG. 5, when the angle θ is 25 °, good results are obtained when the length L range of the commutator 192 is set to 6 mm to 9 mm, and the angle θ is obtained. Is 20 °, good results are obtained when the length L of the commutator 192 is set to 6 mm to 12 mm.

In the experiment of the fabric quality shown in FIG. 6, when the angle (theta) is 25 degrees, a good result is obtained when the length L range of the commutator 192 is set to 6 mm-12 mm. Moreover, although the case where the nylon taffeta is woven in this experiment is shown, when the polyester taffeta is woven, although not shown, the length L of the commutator 192 when the angle (theta) is 20 degrees is shown. = In the range of 6 mm to 12 mm It became a display and (triangle | delta) was made in all other angles (theta) = 15 degrees-30 degrees, and length L (range) = 5 mm-12 mm. Although the proper weft speed also differs about other cloth types, it is the range of angle ((theta)) = 20 degrees-25 degrees which obtains the best result especially in the range of length (L) = 6 mm-12 mm.

In addition, the larger the angle θ, the higher the weft velocity, but since the limit of the weft tip vibration is angle θ = 30 °, the angle θ over 30 ° is omitted in both FIGS. 5 and 6. .

In the first embodiment, the following effects can be obtained.

(1-1) The configuration in which the angle θ of the tapered hole 171 was 25 ° and the length L of the commutator 192 was in the range of 6 mm to 9 mm has a water collection rate of 16% or more and weft insertion stability. Both in valuation and in decency evaluation Get the result of the display. Therefore, the configuration in which θ = 25 ° and L = 6 mm to 9 mm is optimal for achieving the weft insertion rate of about 2000 m / min to about 2500 m / min without raising the pump pressure than before.

(1-2) The structure which made the angle (theta) of the taper hole 171 into 25 degree and the length L of the commutator 192 into the range of 6 mm-12 mm has a water collection rate of 16% or more, and weft insertion stability. There is some △ mark in the evaluation of, but all in the evaluation above Get the result of the display. That is, in evaluation of cloth quality, the same result as the case of the structure which made (theta) = 25 degrees and L = 6mm-9mm is obtained. Therefore, it can be said that the configuration in which θ = 25 ° and L = 6 mm to 12 mm is close to optimum for achieving the weft insertion rate of about 2000 m / min to about 2500 m / min without raising the pump pressure than before. .

(1-3) The structure which set the angle (theta) of the taper hole 171 to 20 degrees-25 degrees, and length L of the commutator 192 in the range of 6 mm-9 mm has a water collection rate of 16% or more, In the evaluation of weft insertion stability, all In the evaluation of labeling and quality of goods, the ○ mark brings many results. Therefore, the configuration in which θ = 20 ° to 25 ° and L = 6 mm to 9 mm is very preferable to achieve the weft insertion rate of about 2000 m / min to 2500 m / min without raising the pump pressure than before. .

(1-4) The structure which set the angle (theta) of the taper hole 171 to 20 degrees-25 degrees, and the length L of the commutator 192 in the range of 6 mm-12 mm has a water collection rate of 16% or more, In the evaluation of weft insertion stability, even in the evaluation of some △ mark and fabric quality Marking has many results. Therefore, the configuration in which θ = 20 ° to 25 ° and L = 6 mm to 9 mm is considerably preferable to achieve the weft insertion rate of about 2000 m / min to 2500 m / min without raising the pump pressure than before. .

(1-5) The structure which set the angle (theta) of the taper hole 171 to 15 degrees-30 degrees, and the length L of the commutator 192 in the range of 5 mm-12 mm has a water collection rate of 15% or more, The weft insertion stability and fabric quality also result in more than △ mark. Therefore, the configuration in which θ = 15 ° to 30 ° and L = 5 mm to 12 mm is preferable to achieve the weft insertion rate of about 2000 m / min to about 2500 m / min without raising the pump pressure than before.

(l-6) Combining the results of the collection rate of FIG. 4 and the result of weft insertion stability evaluation of FIG. 5, the amount of shaking tends to increase as the collection rate decreases and moves to the 15% side. That is, it is thought that the amount of shaking of the tip of the weft is affected by the collection rate. When the length L of the commutator 192 is in the range of 5 mm to 12 mm and the angle θ is in the range of 17 ° to 26 °, the collection rate is 16% or more. At catch rate of 16% or more, weft insertion stability Display ratings increase. Accordingly, the configuration in which the length L of the commutator 192 is set to 5 mm to 9 mm and the angle θ to 17 ° to 26 ° does not increase the pump pressure than conventionally, and it is about 2000 m / min to about 2500 m / min. It is preferable to achieve the weft insertion rate of.

(1-7) This embodiment demonstrates the diameter d of the inner hole 122 of the nozzle main body 12 as 7 mm. However, the length L of the commutator 192 in the weft yarn Y conveyance direction in the weft guide needle 14 is 0.71 to 1.71 times the diameter d of the inner hole 122 of the nozzle body 12. In the range of, the same result as described above is obtained.

(1-8) Putting together the results of (1-1) to (1-7), the angle θ of the tapered hole 171 is set to 15 ° to 30 °, and the length of the commutator 192 ( The configuration in which L) is 0.71 times to 1.71 times the diameter d of the nozzle body 12 inner hole 122 does not increase the pump pressure than before, and 2000 m / min while securing weft insertion stability and fabric quality. It is preferable to achieve a weft insertion rate of about 2500 m / min.

(1-9) The diameter d of the inner hole 122 of the nozzle main body 12 in the general weft insertion nozzle is about 7 mm-8 mm. This dimension is set in consideration of miniaturization so that weft can be inserted into the inclined opening even when a plurality of weft insert nozzles are provided in parallel while ensuring the quantity of water that can be inserted into the weft inserting end to be sure. The structure which made the length L of the commutator 192 into 5 mm-12 mm is preferable when it applies to the general weft insertion nozzle of the diameter (d) of the inner hole 122 = 7 mm-8 mm.

(1-10) The water injected from the weft insertion nozzle 10 diffuses, and when this diffusion is large, the collection rate falls. The largely diffused jet water collides with the slope to lower the quality of fabric. When the installation position of the weft insertion nozzle 10 shown in FIG. 8 becomes a position similar to the conventional one, in this embodiment which the collection ratio improved compared with the past, the opening angle (alpha) of the inclination T can be made small. The configuration in which the opening angle α is made smaller than in the prior art contributes to shortening of the reciprocating amount (time) of the seed light 22, that is, to speeding up the loom. When the opening angle α of the inclination T is made to be the same as in the prior art, in this embodiment in which the water collection rate is improved than in the prior art, the installation position of the weft insertion nozzle 10 can be made closer to the immediately preceding W1 of the woven fabric W than in the prior art. have. That is, the position where the lid 23 retreats most can be made close to the immediately preceding W1, which contributes to shortening the swing amount (time) of the lid 23, i.e., speeding up the loom.

Next, the second embodiment of FIG. 9 will be described. The same code | symbol is attached | subjected to the same structural part as 1st Embodiment.

The ring portion 241 of the rectifying means 24 in this embodiment has a tapered shape in which the diameter is reduced toward the tip side from the rear end side of the commutator 242. The inner circumferential surface 243 of the ring portion 241 is continuously connected to the taper hole 171 of the injection port forming body 17. The configuration in which the inner circumferential surface 243 is continuously connected to the tapered hole 171 contributes to the reduction of the flow path resistance in the flow path leading to the flow path 173 narrowing between the commutators 242. The length L of the commutator 242 is the average length in the conveying direction R of the weft yarn Y in the weft yarn guide needle 14.

In the present invention, the number of commutators may be appropriately changed to 16, 18, 22, and the like.

As described in detail above, the angle of the taper hole is in the range of 15 ° to 30 °, and the length of the commutator in the weft feed direction in the weft guide needle is 0.71 times to 1.71 with respect to the bore diameter of the nozzle body. Since the thickness is in the range of 5 mm to 12 mm, the weft insertion rate can be improved while securing the weft insertion stability and the quality of the fabric without increasing the power consumption.

Claims (2)

A water channel is formed between the outer circumferential surface of the weft guiding needle 14 inserted into the nozzle body 12 and the inner circumferential surface of the nozzle body 12, and the pressure water is supplied from the injection port 20 by supplying pressure water to the water channel. In the weft insertion nozzle for weft inserting the weft (Y) passed through the weft guide needle 14 by the injection water with the injection water, Rectifying means (19) formed by arranging a plurality of commutators (192) in an annular manner in said waterway around said weft guide needle (14), and In the waterway on the downstream side of the plurality of commutators 192, the inner circumferential surface of the tapered hole 171 and the weft thread guide needle 14 is reduced in diameter toward the jet port 20 from the commutator 192 side It is provided with a narrowing flow path 173 formed between the outer peripheral surface of the, While the angle of the taper hole 171 is in the range of 15 ° to 30 °, the length of the commutator 192 in the weft yarn Y conveying direction R in the weft thread guiding needle 14 is measured. A weft insertion nozzle of a water yarn loom having a range of 0.71 times to 1.71 times the diameter d of the inner hole 122 of the nozzle body 12. A water channel is formed between the outer circumferential surface of the weft guiding needle 14 inserted into the nozzle body 12 and the inner circumferential surface of the nozzle body 12, and the pressure water is supplied from the injection port 20 by supplying pressure water to the water channel. In the weft insertion nozzle for weft inserting the weft (Y) passed through the weft guide needle 14 by the injection water with the injection water, Rectifying means (19) formed by arranging a plurality of commutators (192) in an annular manner in said waterway around said weft guide needle (14), and In the waterway on the downstream side of the plurality of commutators 192, the inner circumferential surface of the tapered hole 171 and the weft thread guide needle 14 is reduced in diameter toward the jet port 20 from the commutator 192 side It is provided with a narrowing flow path 173 formed between the outer peripheral surface of the, While the angle of the taper hole 171 is in the range of 15 ° to 30 °, the length of the commutator 192 in the weft yarn Y transfer direction R in the weft yarn guide needle 14 is 5 mm. Weft insertion nozzle for water yarn looms with a thickness of 12 mm.