JPH01314753A - Weft-inserting unit in jet loom - Google Patents

Abstract

PURPOSE:To provide the title unit so designed that an auxiliary nozzle injection tip is located at a position of the lowermost height of the weft-inserting channel, and the both upper and lower walls and deep wall of guide holes are tilted against the weft-inserting direction to control fluid leakage to suppress weft running troubles, thereby enhancing the running speed. CONSTITUTION:In a jet loom, an injection tip 2a of a weft-inserting auxiliary nozzle 2 is located at a position of the lowermost height of the weft-inserting channel S formed with a row of guide holes 4 of deformed guide bars 3. Each of said guide holes 4, being approximately tetragonal, is formed by a nearly horizontal upper wall surface 4a, a nearly perpendicular deep wall surface 4b and a lower wall surface 4c somewhat tilted against said upper wall surface 4a with the inclination of said upper wall surface 4a greater than that of the deep wall surface 4b for the weft inserting direction P; thereby controlling fluid leakage from the releasing port of the guide holes 4 along with properly arranging the pulling action of weft yarns due to said fluid leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a weft insertion device using a modified reed having guide holes in the front surface of the reed.

[Prior Art] As a method for increasing the speed of the weft yarn flying through the weft insertion path formed by the rows of guide holes of the modified reed, for example, Japanese Patent Publication No. 59-26688 and Japanese Patent Publication No. 60-148 disclose
As disclosed in Japanese Patent No. 65, there is a method in which the wall surface of the guide hole is inclined with respect to the weft insertion direction to prevent leakage of air flowing in the weft insertion passage and increase the flow velocity. Special Public Service 1987
In Publication No. 26688, the upper wall surface, lower wall surface, and back wall surface forming the guide hole are set at the same angle of inclination.
In 0i4865, the upper wall surface and the lower wall surface are sloped, and the back wall surface is not sloped.

In both cases, as the inclination angle of the guide hole forming wall surface increases, the flow velocity increases, and the flying speed of the weft yarn can be increased.

[Problems to be Solved by the Invention] However, in the case of Japanese Patent Publication No. 59-26688, air leakage from the opening of the guide hole increases as the inclination angle increases, and the weft yarn is carried by this leakage air. There are many cases where the leading edge jumps out from the weft insertion path, resulting in flying problems. In the case of Japanese Patent Publication No. 60-14865, the amount of air leaking to the outside between the non-slanted back wall surfaces of each reed blade is larger than the amount of leakage from between the sloped back wall surfaces, and this air leakage is caused by It works to attract the tip of the weft yarn in the input passage toward the back wall surface. Therefore, although the rate of occurrence of flying troubles is extremely low, this air leakage causes a relatively large decrease in the flow velocity in the weft insertion passage, which impedes an increase in the weft flying speed.

Special Publication of 1977 featuring a closed type weft guide
In Publication No. 23357, the angle of inclination of the wall surface of the inner part facing the thread removal section is set to be larger than the other forming wall surfaces, and the effect of moving the weft tip away from the thread removal section is obtained. Unlike a weft guide, in a modified reed in which the reed blades are closely adjacent to each other, if the inclination angle of the back wall surface is set large, air leakage from between the back wall surfaces will be reduced, and flying problems will occur frequently.

SUMMARY OF THE INVENTION An object of the present invention is to provide a weft inserting device using a modified reed, which can both increase the flying speed of the weft thread and reduce flying troubles.

[Means for Solving the Problem] To achieve this, in the present invention, the injection port of the weft insertion phase auxiliary nostle is set near the open end of the lower wall surface of the guide hole consisting of the upper wall surface, the lower wall surface, and the inner wall surface, and The injection direction of the weft insertion auxiliary nozzle is set so as to have an injection flow path that intersects the wall surface and the back wall surface, and an inclination is provided on the upper wall surface and the back wall surface that enters the weft insertion path as it goes toward the weft insertion direction, and The angle of inclination of the upper wall was made larger than the angle of inclination of the back wall.

[Function] The air jetted from the auxiliary nozzle for weft insertion exclusively hits the upper wall surface and the back wall surface. A part of the air heading toward the back wall surface leaks from the back wall surface, and this air leakage brings about the effect of attracting the flying weft yarn from the open opening toward the back wall surface side. The reflected flow from the back wall surface is suppressed by the reflected flow from the upper wall surface, and the counterflow from the back wall surface or leakage from the open opening is suppressed. The balance between this leakage suppressing Hil1 effect and the above-mentioned attracting effect influences the flow velocity in the weft insertion passage and the occurrence rate of flying l/rubble, but the angle of inclination of the back wall surface is made smaller than the angle of inclination of the upper wall surface. As a result, the balance between the leakage suppressing effect and the pulling effect can be set most appropriately, and the weft flying speed can be increased while suppressing the occurrence rate of flying troubles.

[Example 1] Hereinafter, an example embodying the present invention will be described based on the drawings.

An auxiliary weft insertion nozzle 2 is attached to the front of the sleigh 1 so that its mounting position can be adjusted in the weft insertion direction, and the injection port 2a of the weft insertion auxiliary nozzle 2 is formed by the row of guide holes 4 of the deformed reed 3. It is set at the lowest height position of the weft insertion path S. The guide hole 4 of the deformed reed 3 is formed on a substantially horizontal upper wall surface 4a.
It is formed into a substantially rectangular shape by a substantially vertical back wall surface 4b and a lower wall surface 4c slightly inclined with respect to the upper wall surface 4a, and each wall surface 4a, 4b, and 4c is inclined with respect to the weft insertion direction. It is being

The inclination angle θ2 of the rear wall surface 4b shown in FIG. 2 is set to approximately half the inclination angle θ1 of the upper wall surface 4a shown in FIG. is set the same as. As shown by arrow P in FIGS. 1 to 3, the injection direction I) of the injection port 2a near the open end of the lower wall surface 4c is set to point near the boundary between the upper wall surface 4a and the inner wall surface 4b. The jet flow path delimited by the outer streamline ρ intersects the upper wall surface 4a and the inner wall surface 4b.

Since the inclination angle θ2 of the back wall surface 4b is relatively small, a part of the jet flow toward the back wall surface 4b (indicated by the symbol Δ) leaks from between the back wall surfaces 4b as shown in FIG.
Since the inclination angle θ1 is set relatively large, the proportion of the jet flow toward the upper wall surface 4a leaking from between the upper wall surfaces 4a is small, and the proportion of the jet flow directed toward the upper wall surface 4a is high. The reflected flow from the upper wall surface 4a having a large reflection ratio suppresses the effect of the reflected flow from the inner wall surface 4b toward the opening of the guide hole 4. Therefore, the main nozzle 5 for weft insertion
The weft created from the weft to the weft insertion passage S flies through the weft insertion passage S while receiving the leakage effect from between the back wall surfaces 4b and the leakage suppressing effect from the opening number of the guide hole 4.

The curve C1 in FIG. 4 represents the slope angle θ1 of the upper wall surface 4a and the back wall surface 4.
The weft flying speed is shown when the inclination angle θ2 of b is made equal, and the curve C2 shows the flying speed in the case of this example. When the inclination angle θ2 is made equal to the inclination angle θ1, fluid leakage from between the inner wall surfaces 4b is reduced, and a decrease in flow velocity due to this fluid leakage is reduced. Therefore, the rate of increase in weft speed as the inclination angle θ1 increases in the case of θ1-02 is higher than in the case of the present embodiment (θ1>θ2), which is convenient for increasing the weft flying speed. However, when the weft flying speed exceeds a certain limit (indicated by The effect of suppressing the action directed toward the opening of No. 4 by the reflected flow from the -1-wall surface 4a is rapidly reduced due to the reduction in fluid leakage from between the back wall surface 4b, and
Fluid leakage from the opening of the guide hole 4 due to the irregular flow rate increases rapidly. As a result, flying druffles in which the weft tip jumps out of the weft insertion path S occur frequently, and the coordinate point x (α, ■1) represents the limit of weft insertion stability.

In the case of this embodiment (θ1>θ2), the fluid leakage effect from between the inner wall surfaces 4b and the suppressing effect due to the reflected flow from the upper wall surface 4a are efficiently matched, and the limit Y at which flight troubles occur frequently is the coordinate point X(α.

The limit of weft insertion stability expressed by V, ) is exceeded.

Express the limit Y by the coordinate point Y (β, V2), if β>α and v
2>vl, and by appropriately increasing the inclination angle θ1, it is possible to increase the weft flying speed while suppressing flying troubles. This is because the action of suppressing fluid leakage from the opening of the guide hole 4 and the action of pulling the weft yarn due to fluid leakage from between the inner wall surface 4b are obtained by appropriate matching, and this proper matching This is obtained by making the inclination angle θ2 of the rear wall surface 4b smaller than the inclination angle θ1 of the second wall surface 4a.

Of course, the present invention is not limited to the above-mentioned embodiments. For example, the injection direction of the weft insertion auxiliary nozzle 2 is
It may be set to point toward the upper wall surface 4a or the rear wall surface 4b from the boundary between the upper wall surface 4b and the rear wall surface 4b. control is carried out effectively. Further, the angle of inclination of the lower wall surface of the guide hole may be made to match the angle of inclination of the inner wall surface.

Furthermore, when viewed from the weft insertion side as shown in FIG. 1, the back wall surface 4b is not limited to a wall surface that is straight in the longitudinal direction of the reed blades as in the embodiment, but may be formed into a curved or almost curved wall surface. The present invention can also be practiced.

[Effects of the Invention] As detailed above, the present invention sets the injection direction of the auxiliary nozzle for weft insertion so as to have an injection flow path that intersects the upper wall surface and the back wall surface, and inserts the weft into the upper wall surface and the back wall surface. Since the angle of inclination of the upper wall surface is made larger than the angle of inclination of the rear wall surface, it is possible to appropriately control the reflected flow from the rear wall surface by the reflected flow from the upper wall surface, that is, from the opening of the guide hole. It is possible to appropriately match the action of suppressing fluid leakage between the inner wall surface 4b and the action of pulling the weft yarn due to fluid leakage from between the back wall surfaces 4b, thereby increasing the weft flight speed while suppressing the occurrence of flying troubles. It has excellent effects.

[Brief explanation of the drawing]

The drawings show an embodiment embodying the present invention; FIG. 1 is a side sectional view, FIG. 2 is an enlarged sectional view taken along line A-A in FIG. 1, and FIG. 3 is taken along line 13-B in FIG. 1. The enlarged sectional view, FIG. 4, is a graph showing the relationship between the inclination angle of the upper wall surface and the weft flying speed. Weft insertion auxiliary nozzle 2, injection port 2a, deformed reed 3, guide hole 4, upper wall surface 4a, back wall surface 4b, weft insertion passage S, inclination angle θ1. θ2, injection direction P.

Claims (1)

[Claims] 1 The weft is ejected from the main nozzle for weft insertion toward the weft insertion path formed by the row of guide holes recessed in the front surface of a large number of reed blades, and the jet stream is ejected from the plurality of auxiliary nozzles for weft insertion. In the jet loom that assists the flight of the weft yarn in the weft insertion passage, the injection port of the weft insertion auxiliary nozzle is set near the open end of the lower wall surface of the guide hole consisting of an upper wall surface, a lower wall surface, and a back wall surface. The injection direction of the weft insertion auxiliary nozzle is set so as to have an injection flow path that intersects with the upper wall surface and the back wall surface, and an inclination is provided on the upper wall surface and the back wall surface so that the weft insertion path enters the weft insertion path as it goes in the weft insertion direction. Also, a weft insertion device in a jet loom in which the angle of inclination of the upper wall surface is larger than the angle of inclination of the back wall surface.