JPS63145449A - Nozzle type loom - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a nozzle-type loom that is equipped with a main nozzle for feeding the weft yarn into the lightweight mouth section and several staff nozzles arranged one behind the other in the weft feeding direction. The staff nozzle is formed from straight tubules, closed at their free ends and pointed in the form of a blade, which are attached to a force 1 sley 1; At least one air outlet is provided on the flat side surface, and the air outlet is directed from below obliquely to the weft feeding direction into the U-shaped conduit formed by the reed feathers. related to things.

[Problems to be solved by the prior art and the invention] In this type of nozzle type loom, in order to enable reliable and failure-free feeding of the conduit formed by the blades, it is necessary to There is a problem in filling the air with conveying air. On the other hand, however, the energy consumption of nozzle looms must be kept as low as possible, so the air consumption should be kept as low as possible.

Practice has shown that different woven materials also require different intensities of air flow. For example, thick cotton strands may be carried better with weaker airflow than filament yarns, which require stronger airflow. In practice, it is therefore necessary to operate the staff nozzle at various overpressures.

It is known to provide a staffen nozzle with an air outlet in the form of a round hole (West German Patent Application Publication No. 2119238).
In the case of a staff nozzle of this type, the blowing direction is determined by the applied overpressure in the case of large hole diameters.

It was found that it moves during overpressure fluctuations. A staff nozzle of this type is therefore only useful if the same material is always being processed and there is no need for changes in air pressure.

It is also known (West German Patent No. 2,522,335) to provide a large number of individual holes arranged like a sieve instead of one large hole as the air outlet for the Staffen nozzle. These individual holes are supposed to split the air into a number of separate streams, which are then merged back into a single stream at a very short distance from the outlet. It has been found that when selected and properly arranged, nr trs improves the stability of the blowing direction and obtains the same blowing direction even at different overpressures. However, each of these individual holes contributes to flow losses that add up to lead to an overall loss that is greater than for a single large hole. Moreover, machining a large number of individual holes is quite laborious and expensive. In addition, small holes become clogged relatively easily, and in that case they must be painstakingly cleaned, especially by using aW waves.

It is also known to provide a Statzfätzten nozzle with an outlet in the shape of a ridged star. With this structure, the air flow blown out is separated from the outlet point of the blow-off port, and the outer circumferential surface of the flow that comes into contact with the surrounding air becomes significantly larger. Therefore, the blown air flow entrains a relatively large amount of surrounding air as so-called secondary air, so that a relatively large volume of air flow is created with a relatively small amount of blown air. The stability of the outlet direction when the overpressure fluctuates is slightly improved compared to the only round hole outlet structure. However, this directional stability is decisive in this construction type, as long as a relatively large volume of air flow is created on the basis of secondary air entrainment and reaches in each case into the conduit formed by the wings. It has no role to play.

The present invention provides for a nozzle loom of the type mentioned at the outset, which on the one hand guarantees a high directional stability of the blowing direction even under various overpressures and produces an air flow of as large a volume as possible;
In addition, the objective is to provide a Stadtsfetten nozzle that can be manufactured as simply as possible.

[Means for solving the problem] The problem is that the air outlet always has the shape of a slit that extends almost perpendicularly to the center line of the small tube, and its width is 0.8 mm.
l or less, and its side walls are contoured in such a way that the smallest flow cross section is limited, at least on one side, by an edge whose thickness is less than or equal to 0.2s+s.

[Function] The present invention is based on a physical phenomenon which, based on a high air overpressure of 2 to 7 bar, is always in a supercritical state and can therefore be called a "critical flow cross section", which is decisive for the blowing direction. It is based on the knowledge that there is. The critical flow cross-section is the point at which the expansion of the air flowing through the Stadsfüdden nozzle begins. The direction of the corresponding outlet stream is not directly dependent on the direction of the hole, but rather is oriented perpendicular to this "critical flow cross section". Explosive expansion occurs at this critical flow cross section. In known constructions, the critical flow cross section is not the same as the outlet except in special cases, and furthermore, this critical flow 8! ! It has a special property that the position of the cross section can change depending on the overpressure. Depending on the height of the overpressure, the critical flow cross section moves inside the outlet and can be set obliquely towards the center line of the outlet or even into the small tube.

The smaller the overpressure, the more the critical flow cross section moves into the outlet and also into the small tube. This applies to an extreme degree for round, relatively large single holes (DE 2119238), but also for star-shaped single holes arranged in a sieve-like manner (DE 2522335). This also applies to According to the invention, it is achieved that the critical flow cross-section remains in each case within the area of the outlet, and in particular also at a specific position of this outlet. The blowing direction of the stream of compressed air blown out is therefore constant over a very large overpressure range. In the structure according to the invention, the cross section of the slit is substantially flat when the critical cross section lies on a substantially flat side. It can even be asymmetrical about the lateral side while the blowing direction is still perpendicular to this side.

Moreover, the blown flow has the advantage that the surface in contact with the surrounding air is already enlarged at the exit point of the outlet, and a correspondingly large amount of secondary air is entrained, resulting in the formation of a large-volume flow. is obtained. Furthermore, the advantage is that the machining of such slit-like holes is less demanding in terms of manufacturing than, for example, the machining of a large number of sieve-shaped holes.

Other features and advantages of the invention will become apparent from the subsequent description of the embodiments and from the claims.

[Example] The sleigh 5 of the nozzle-type loom shown in a partially transparent view in FIG. 1 has a shaft 2 driven into reciprocating motion in the direction of the double-headed arrow by a drive unit not shown! There is. A profile beam 23 is mounted on the shaft 21 by means of a holder 22 and extends parallel to the shaft 21, which supports the reel 8 and between which the warp threads 19 and 20 are guided. Two warp threads 19.20 are shown. In practice, one warp thread 19 or 20 passes between each of the reed feathers 8.

The warp threads 19, 20 are controlled upwardly and/or downwardly by the shedding device, so that an opening 2 is formed in each case. The weft threads 1 are then fed into this opening 2, and the shedding position is changed to the 0th, where the weft threads 1 are subsequently beaten by the reel threads 8 moving towards the width holding device, and the warp threads 19, 20 are moved to the opposite direction. It is brought into position and a new opening 2 is formed into which the next weft thread l is fed.

The feeding of the weft yarn l is carried out via the main blow nozzle 3,
12 are connected to a compressed air source (not shown) and are fixed on a profile beam 23 with a holder so that the main blow nozzle 3 moves together with the sley 5. The reed feathers 8 form, by projections on their front edges, an approximately U-shaped channel 9 in which the weft threads l are conveyed to the other edge of the fabric.

In order to ensure the feeding of the weft yarn l in the line 9, an air flow is created in the line 9 by means of the staff nozzle 4. These staff nozzles 4 are arranged side by side at regular distances in the direction in which the weft thread I is fed, and compressed air is fed in groups. The Stafeten nozzle 4, which has the shape of a straight small tube, is an opening that is formed each time! It is attached to a beam 23 of the profile 9M which remains on the outside of the shaft 2, and only the end of the staff nozzle 4 protrudes into the opening. A holder 25 is attached to the shaped beam 23.

These support the staff nozzles 4 and are supplied with compressed air in groups via compressed air supply pipes 27 by valves. An air flow is produced via the staff nozzle 4, which fills the line 9 as completely and evenly as possible. Therefore, each staff nozzle should, on the one hand, contain a relatively large volume and, on the other hand, emit an air stream that is directed as closely as possible. The strength of the airflow in the line 9, which is necessary for the uniform feeding of the a-thread l, depends on the material to be treated. For example, when processing thick cotton strands, it is expedient to work with a much weaker air flow than when processing, for example, smooth filament yarns. It is therefore necessary that the blowing air flow of the individual staff nozzles 4, depending on the applied overpressure, be variable in intensity. However, despite this variable strength,
It must be ensured that the blowing direction remains at least approximately constant.

When designing the staff nozzles 4, the structural limitations of these staff nozzles 4 should also be taken into account. The weft thread 4 that moves together with the sled 5 is moved by the weft thread 4.
It comes out of the opening 2 when the sled is struck, and enters the (changed) opening 2 again when the sleigh 5 returns. Therefore, the Stauffet nozzle 4 can have only a relatively small extent, especially at right angles to the warp threads 19,20. The staff nozzle 4 is therefore formed from a relatively thin small tube, which also has a relatively thin wall thickness of about 0.511 ffl, and for this reason the air flow through the outlet of the staff nozzle 4 in a conventional manner. It is not possible to design it as a technically advantageous outlet nozzle. In addition, the staff nozzles 4 must have their outer surfaces as smooth as possible so that the warp threads 19, 20 cannot be caught and damaged.

In order to avoid obstructing the reeling of the fed weft l, the airflow nozzle 4 is placed in front of the reeling blade in the reeling direction and shifted downward, so that the air flow is directed diagonally from below into the pipe. It is so that it is blown into 9. The output nozzle 4 is then oriented in such a way that the blown air stream is directed at an angle of approximately 10'' to the feeding direction of the weft yarn 1.

An air pressure of 2 to 7 bar is applied to the Stauffette nozzle 4 in order to create a sufficiently strong feed air flow in the line 9, in each case supercritical in relation to the possible size of the blowout ``1''. Therefore, the blown air stream expands explosively, and at that time,
Inflation or initiation. A peculiarity appears in that the blowing direction is influenced by the position of the so-called critical flow cross section. In order to precisely determine the position of the critical cross section and thus also to precisely determine the direction of the outlet even at different air pressures, the invention provides for the critical cross section to be located at a specific point of the outlet. For this purpose, connect the air outlet to a small pipe I.
Consider the design as a slit 7 extending approximately at right angles to the axis of the nozzle 4, which is designed as an O. The small tube 10 (FIGS. 2 to 10) has an oval cross-section at least in the region of the long slit 7, and its greatest extent extends in the direction of the warp threads. In the area of the free end, the small tube 10 is sharpened like a blade, and instead of a sharp cutting edge, it is anyway provided with a rounded edge. In the area of the outlet, which is formed as a slit 7, there is an approximately flat surface 6. This flat surface 6 extends perpendicularly to an angle of approximately IO'' in the blowing direction, ie in the feed direction of the weft thread l.The slit 7 has a width of at most 0.81 mm. The idea is that the narrowest cross-section of the forming sluice 7 is in a specific position so that the outlet direction cannot be varied even by pressure-dependent movements of the critical flow cross-section inside the outlet.

In the embodiment of FIG. 5, the idea is that the slit 7 is limited by a side wall surface which widens from the inside to the outside. This creates an internal sharp edge U, which defines the critical flow cross-section at which expansion begins. The direction of the blown flow is therefore the inner edge 11 that limits the slit 7.
perpendicular to the plane between them. A slit of this kind can be made, for example, by discharge erosion, with a cross-shaped electrode whose thickness corresponds to the slit width and whose width corresponds to the slit length, and which is eroded twice, with the 'itt pole each time at a different angle. is applied to the rough surface 6 of the staff nozzle 4. This application is shown in broken lines in FIG.

In the embodiment of FIG. 6, the idea is such that the narrowest cross-section of the slit 7, thus also the critical flow cross-section, lies on the outer or flat surface 6 of the Staff nozzle 4. For this purpose, the idea is that the side wall surfaces converge in the flow direction. This nozzle shape also uses a bar-shaped electrode due to discharge erosion, and the electrode is also inserted into the slit 7 at two different angles.
can be applied twice to obtain the shape shown in FIG. In this embodiment, the critical flow cross section is delimited by two sharp edges 12 extending along the length of the slit 7.

In the embodiment of FIGS. 7 and 8, the wall thickness of the Staff nozzle 4 is reduced in the region of the slit 7 in which the critical flow cross-section, the position of which is precisely defined, is located in the slit 7.
115 to 1/ by space 28.29 in the range of
3, ie to a maximum of 0.2 am. A relatively thin surrounding edge 1:l, 1 thereby defining a critical flow cross-section in the slit 7
I can do 4. In the embodiment according to FIG. 7, the idea is to provide a recess 28 of reduced wall thickness in the area of the slit 7 in the interior of the staff nozzle 4 on the side facing the flat part 6.

In the embodiment of FIG. 8, the idea is here too that a recess 29 is provided from the flat surface 6, which reduces the wall thickness.

Due to the formation of the outlet in the form of a slit 7, the blown air stream also has a relatively large surface already at the beginning, with which it comes into contact with the surrounding air. Due to this relatively large surface, and with a correspondingly large amount of surrounding air, the so-called secondary air, a relatively large air flow still occurs even with a relatively variable amount of blown air. There is.

- If the total cross-sectional area of the two slits 7 is insufficient to blow out a sufficient amount of air, an additional opening, also in the form of a slit 17, 18 and parallel to the slit 7, may be provided. is possible. These slits 17.1
0 defines the width corresponding to the slit 7 and is formed with respect to the wall surface 1. Between the individual slits 7, 17 and 18 there is a crossbar on the order of 0.3 to 1.5 times their width They are arranged at intervals of 3 so that . As shown in Figure 2, in that case, purposefully.

The slits 17, 18 remote from the closed end of the staff nozzle 4, which are formed as small tubes 10, are designed to shorten their length.

In the case of the embodiment shown in FIG. 4, the overall cross-sectional area is enlarged by two slits 7.7° arranged symmetrically in the - plane, each having an obtuse angle and their vertices facing each other.
This can be obtained by providing . This non-parallel configuration achieves that the outer extent of these slit doors, 7°, comes into contact with the surrounding air without interfering with each other and draws in secondary air without interfering with each other.

In the embodiment shown in FIGS. 9 and 1θ, the small tube 10 forming the staff nozzle 4 is provided with a slit 7 having an approximately rectangular outline. A slit 7 perpendicular to the center line 33 of the tubule 10 is bounded on the pointed free end side of the tubule 10 by a side wall 30 perpendicular to the substantially flat side surface 6 . The opposite side 731 likewise forms a smooth surface and is inclined with respect to the substantially flat surface 6 by an angle of about 20@ so that the cross section of the slit converges from the inside to the outside. The minimum flow cross section is
The critical flow cross-section defined by the edge 32 on the side opposite the closed end of the tubule 10 therefore also lies in the substantially planar plane 6.

Both end walls of the slit 7 are parallel to the long axis 33 and side walls zo,
perpendicular to it. The slit is simply an end wall and a side wall: 10,
It is slightly rounded in the range of angles between .31 and .31.

The slit 7 extends in the plane of the substantially flat side wall 30.3.
1, that is, the width between the side wall 30 and the edge 32 is about 0.
The length of the slit 7 between the two end walls, which is 71, is approximately three to four times this width.

As can be further seen in FIG. 10, the tubule 10 is shaped symmetrically about its long sleeve.

That is, on the opposite side of the substantially flat surface 6 there is a corresponding substantially flat surface. These two flat surfaces make an angle of about 20° to each other and thus the center of the canalicula IO! *: 13 and about 10°
The distance from the free end of the tubule to the center of the slit 7, which forms an angle of , is slightly greater than three times the width of the slit between the side wall 30 and the edge 32.

Suriud 7 has an asymmetrical shape with respect to the flat surface 6.
can be made using bar-shaped electrodes, for example by discharge erosion. The cross-shaped electrode has a width corresponding to the length of the slit and a thickness slightly smaller than the width of the slit 7. This electrode is once applied perpendicularly to the substantially flat surface 6 of the canalicule 10, with the side wall 30 and the adjoining end wall being created. After tilting and, if necessary, a movement that determines the slit width, it is applied once more to the canaliculus.

It is clear that, despite the asymmetrical shape of the slit 7 with respect to the substantially flat surface 6, a blowing air stream is produced which is oriented perpendicularly to the substantially flat surface 6 and has extremely high directional stability even at various pressures. It became a thing.

In order to improve the directional stability of the blown air stream perpendicular to the side wall 30.31, in the embodiment of FIGS. It is a provision. The recess 35 has a depth of approximately 0.05 to 0.
．． 2- It is in the shape of a shallow notch in the garden. The apex of this recess is parallel to the slit 7. The length of the recess approximately corresponds to the length of the slit. The side surfaces of this notched recess form an obtuse angle with respect to the inner wall surface. A recess of this kind can be produced, for example, by introducing a corresponding sharpened tool into the slot 7 and thereby pushing the back wall correspondingly outwards. In this case, the bump-like elevation that occurs on the outer wall of the rear wall is then removed by grinding.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a part of a nozzle type loom constructed according to the present invention. FIG. 2 is an enlarged external view of the Staffen nozzle of the embodiment shown in FIG. 1, viewed in the opposite direction to the blowing direction. Figure 3 shows the line m-■ of the Staffen nozzle in Figure 2.
FIG. FIG. 4 is an external view of another embodiment of the Staffen nozzle. Figure 5 has been further enlarged. 1 is a cross-sectional view of a staff nozzle in the region of the outlet, which is designed as a slit and has a critical flow cross section therein; FIG. FIG. 6 is a sectional view similar to FIG. 5 of a staff nozzle with an outlet with a critical flow cross section in the outer wall surface. FIG. 7 is a cross-sectional view in the area of the outlet of a staff nozzle of an embodiment in which the critical flow cross section is shifted to the area of the outer surface of the staff nozzle by reducing the wall thickness. FIG. 8 is a cross-sectional view in the area of the outlet of a staff nozzle of an embodiment in which the critical flow cross-section is transferred to the area of the inner wall surface by means of a cavity in the outer side. Figure 9 has been enlarged approximately 20 times its actual size. FIG. 2 is an external view of the Stauffett nozzle seen in the opposite direction to the blowing direction. FIG. 1O shows a side view of the staff nozzle of FIG. 9. l...Weft 2...Opening 3...Main blowing nozzle 4...Staffetten nozzle 5...Sleigh 6...Flat surface 7...
・Slit 8...Osaba 9...Pipeline
10... Small tube +! ...Inner edge (of the slit) 12.1:1.14...Edge (of the slit) 17.18
...Slit 19.20...Warp 21...Shaft 22...2 holders...Shaped beam
25... Holder 27... Compressed air supply device 28. 29... Recess: IO, :11... Side wall (of the slit) 2... Edge (of the slit)

Claims (1)

[Scope of Claims] 1. A nozzle-type loom comprising one main nozzle for feeding the weft into the warp shedding and several staff nozzles arranged one behind the other in the weft feeding direction, The nozzles are formed from straight tubules, closed at their free ends and sharpened into blades, and mounted on the sley, with a nearly flat side near the distal end. In a loom, the air outlet is provided with at least one air outlet, and the air outlet direction is directed from below obliquely in the weft feeding direction into a substantially U-shaped conduit formed by the reed feathers. Each tubule (10
) is in the form of a slit (7) extending approximately at right angles to the center line of the Edges (11, 12, 1
3, 14, and 32). 2. Nozzle loom according to claim 1, characterized in that the slits (7) are located in recesses (28, 29) in the side surfaces (6) of the small tube (10). 3. The nozzle type loom according to claim 1, wherein the slit (7) is defined by a side wall surface that is obliquely inclined with respect to the side surface (6). 4. According to one of claims 1 to 3, characterized in that the small tube (10) is provided with two or several mutually parallel slits (7, 17, 18). The nozzle type loom described. 5. The small tube (10) is provided with two slits (7, 7'), the slits having an obtuse shape with their apexes facing each other. Nozzle type loom according to one of item 3. 6. Claims 4 or 5, characterized in that crossbars are left between the slits (7, 17, 18) and their width approximately corresponds to the width of the slits (7, 17, 18). The nozzle type loom described in section. 7 The slit (18) farther from the free end of the tubule (10)
The nozzle type loom according to any one of claims 4 to 6, characterized in that the slits (7, 17) closer to the free end are shorter in length than the slits (7, 17) closer to the free end. 8. The tubule (10) has a flat oblong cross-section at least in the area of the slit (7), the larger dimension of which extends in the longitudinal direction of the slit (7) and approximately along the warp threads (9, 20).
) The nozzle type loom according to any one of claims 1 to 7, characterized in that the nozzle type loom extends in the direction of . 9. The side wall (30) delimiting the slit (7) on the free end side of the tubule (10) extends at least approximately perpendicular to the substantially flat side (6), and the opposite side wall (31) has a thin 9. Nozzle loom according to claim 1, characterized in that a rim (32) is provided. 10 Side wall (31) opposite the free end of the tubule (10)
10. A nozzle loom according to claim 9, characterized in that the slits (7) are inclined to substantially flat sides (6) so that the slits (7) converge outwards. 11. According to claim 10, the side wall (31) opposite the free end of the tubule (10) is inclined at an angle of about 20° to a substantially flat side (6). Nozzle loom. 12. Claims 1 to 11, characterized in that the center of the slit (7) is at a distance corresponding to approximately three times the width of the slit (7) to the free end of the tubule (10). One of them is a nozzle type loom. 13. Nozzle type loom according to one of claims 1 to 12, characterized in that the length of the slit (7) is approximately 3 to 4 times the width of the slit (7). . 14. One of claims 1 to 13, characterized in that the end walls of the slit (7) are at least approximately perpendicular to the side walls (30, 31) of the slit (7). The nozzle type loom described in. 15. According to claims 1 to 14, the substantially flat sides (6) of the tubule are inclined at an angle of approximately 10° to the center line of the tubule (10). One of the nozzle type looms mentioned. 16. Claims 1 to 1, characterized in that the back wall of the small tube (10) facing the slit (7) is provided with a recess (35) inside and extends substantially parallel to the slit. Nozzle type loom according to one of item 15.