EP0967315A1 - Device having a nozzle manifold generating liquid jets for interlacing fibers on a textile web - Google Patents

Abstract

The appts. to bond a textile web, using water jets to tangle the material fibers, has a jet beam (1) which moves to and fro at right angles to the direction (32) of the material (31) movement. The jet beam (1) is coupled to a mechanism which gives a rapid reciprocating movement, such as a vibrator which alone gives the rapid and changing swing movements (37). The swing movements (37) of the jet beam (1) are in a frequency of at least 10 Hz for a fabric (31) movement speed of at least 1 m/min. The jets have a dia. of ≤ 0.1 mm, and the amplitude of the beam swing movements is ≤ 50% of the jet interval in the jet plate, but ≤ 20 mm such as for a jet interval of at least 0.32 mm in a density of 40 holes/inch. The jet water pressure is at least 30 bar. The prodn. speed (V) to give the forwards movement of the textile material is dependent on the equation: V ≤ Wmax x b divided by l, where the max. speed Wmax=F x A x 2 pi and F is the frequency of the reciprocating movement(1/s,Hz), A is the amplitude (m), b the material width (m) and l the strip interval (m). The value b is d x mu where d is the jet opening dia., and mu a factor relating to the material for the strip development. The amplitude of the jet beam (1) swing movements is 0.32-30,0 mm, and pref. 5-10 mm. The jet beam (1) swings at a frequency of 10-200 Hz and pref. 50 Hz. The oscillating forces from the vibrator are applied at the center of gravity of the jet beam (1), and the vibrator is independent of the carrier housing in a suspension at the jet beam (1). The assembly can have a number of jet beams in succession, with alternating fiber web underlays which are permeable to water, with jet beam movements through a vibrator at only the final or the last two jet beams. Or the assembly has two jet beams, both with swing movements against each other.

Description

The invention relates to a device with a nozzle bar for production from liquid jets to the jet interlacing of the fibers one across the nozzle bar by means of a liquid-permeable base, textile web moved forward, such as Fiber web, which consists of a extending over the working width of the fiber web Upper part and a liquid-tight attached lower part there, in which Upper part is arranged over its length a pressure chamber, which is under pressure standing liquid z. B. supplied on the front and a nozzle plate on the lower part the holes for the nozzles are stored liquid-tight.

A device of this type is known from US-A-4 069 563. The nozzle plate must be provided with holes very close to each other so that due to the A large number of nozzle jets per unit distance sufficient solidification of the Fiber web can be achieved. Because of the strength of the nozzle plate the number the nozzle openings per cm is a limit is in the US patent proposed the nozzle openings in two rows in the nozzle plate of the nozzle bar and then drill the holes to each other, possibly in three rows to be staggered one behind the other. This measure creates a high density the jets next to each other. Nevertheless arise with this arrangement and Use of the nozzle bar with the naked eye detectable characteristic line-shaped Streaks in the surface of the consolidated fiber web.

1. Bei stationärem Düsenbalken eine hier gewünschte gerade Linienprägung infolge der Prägewirkung der Düsenstrahlen und

2. bei hin und her bewegten Düsenbalken eine gewünschte Prägung in Kurven- oder Zickzack-Form. Die Form der Kurven auf dem Vlies ist abhängig von der Frequenz der Schwingbewegungen, jedoch ist nur eine Frequenz von maximal 5 Hz vorgesehen. Über die Amplitude der Bewegungen ist gar keine Aussage gemacht. Die auf diese Weise erzielte Prägung ist gemäß Angabe weicher, die erzielte Oberfläche ist glatter.

In this context, US-A-3,493,462 is important. There, several nozzle bars of this type are held across an endless belt in a frame, which can be caused to oscillate by means of a device in one corner of the frame. The frequency should be around 200 - 300 movements per minute, i.e. 2 - 5 Hz, and the base for the fiber web should either consist of a sheet, a sieve with fine holes or a fabric with greater permeability. The document reveals two options for surface embossing under various test conditions:

1. In the case of a stationary nozzle bar, a straight line embossing desired here as a result of the embossing effect of the nozzle jets and

2. When the nozzle bars move back and forth, a desired embossing in curve or zigzag shape. The shape of the curves on the fleece depends on the frequency of the oscillating movements, but only a maximum frequency of 5 Hz is provided. No statement is made about the amplitude of the movements. The embossing achieved in this way is softer, the surface obtained is smoother.

EP 0 132 128 B1 should also be mentioned here. There is also a frame with several juxtaposed nozzle bars disclosed, the total to be brought into an oscillation oscillation. In contrast to the US PS a fleece with an embossed surface lying on the base is produced, which shows the negative image of the pad used. The operating conditions there is also an oscillation frequency of 75 to 200 movements per minute 1 - 3.3 Hz with an amplitude of 5 - 50 mm. In one example, one Forward speed of the fleece of 10 m / minute, the frequency of 2 Hz and one Amplitude of 37 mm selected. With these values the desired embossing of the Fleece achieved with the structure of the pad, on the surface design on the Nothing is said on the impact side of the jet.

The invention has for its object to develop a device with which the water jet directly affected surface is affected so that it is a uniformly dense and of groove-shaped plastic depressions, which by the Nozzle jets originate, free appearance, although the fiber web as before is only moved lengthways past the bar.

a) ein Düsenbalken allein in Richtung senkrecht zur Bewegungsrichtung der Bahn längs hin und her beweglich gelagert ist,

b) der Düsenbalken zur aktiven Bewegung derart senkrecht zur Bewegungsrichtung der Bahn kraftschlüssig mit einer Einheit für schnelle Hin- und Herbewegungen, wie ein Vibrator, verbunden ist, der allein nur den einen Düsenbalken in kurzfristig sich ändernde Schwingbewegungen versetzt,

c) die Schwingbewegungen des Düsenbalkens eine Frequenz von mindestens 10 Hz bei einer Vorwärtsbewegung der Faserbahn von mindestens 1 m/Min aufweist,

d) der Durchmesser der Düsenlöcher ≤ 0,1 mm beträgt,

e) die Amplitude der Schwingbewegungen ≤ 1/2 des Abstandes der Löcher im Düsenblech, aber < 20 mm, wie z. B. bei einem Lochabstand im Düsenblech von 40 hpi mindestens 0,32 mm beträgt und

f) der Wasserdruck der Wasserstrahlen mindestens 30 bar aufweist.

Starting from the device initially mentioned, the solution to the problem is that

a) a nozzle bar is mounted so that it can move back and forth in the direction perpendicular to the direction of movement of the web,

b) the nozzle bar for active movement is connected in a force-locking manner perpendicular to the direction of movement of the web with a unit for rapid back and forth movements, such as a vibrator, which only sets the one nozzle bar into oscillating movements which change briefly,

c) the oscillating movements of the nozzle bar have a frequency of at least 10 Hz with a forward movement of the fiber web of at least 1 m / min,

d) the diameter of the nozzle holes is ≤ 0.1 mm,

e) the amplitude of the oscillatory movements ≤ 1/2 the distance between the holes in the nozzle plate, but <20 mm, such as. B. at a hole spacing in the nozzle plate of 40 hpi is at least 0.32 mm and

f) the water pressure of the water jets is at least 30 bar.

Basically, only one nozzle bar should be brought into the oscillation movements per unit. The masses to be accelerated again and again in the short term to achieve the goal according to the invention are very high even with a nozzle bar. Then the operating conditions of the individual movements are limited according to a mathematical law. In order to be able to achieve a microscopically smooth surface with individual liquid jets, which always leave a depression in the fleece or in the woven or knitted fabric, the radiation depressions produced must be immediately adjacent or even overlap without a gap.

A) shows a fleece in cross section, perpendicular to the fleece movement.

The water jets hitting the surface are at a distance l from each other, the number of nozzle jets in the nozzle plate, for. B. 40 hpi. In this example, l = 0.65 mm. A jet of water from a hole in one Nozzle plate has a certain larger diameter when it hits the fleece, a linear depression due to the forward movement of the web b causes. The actual deepening is still dependent on a material-dependent one Factor µ, which depends on the respective good, on the type of fiber used, on the previous consolidation and the like. In Figure B) is a top view the appearance shown in Fig. A). By oscillating the invention Nozzle bar incline the line-shaped depressions that always arise right or left. This inclination must be such that the recesses with their Touch the outer edges or even cover them slightly. The decisive factor is the frequency f the oscillating movement, its amplitude A ∧ and the fleece speed V.

Wmax = F x A x 2 π und

F = Frequenz der Hin- und Herbewegung (1/s, Hz)

A ∧ = Amplitude (m),

b = Streifenbreite auf der Warenbahn (m) und

l = Streifenabstand (m) ist. Bei noch genauerer Berechnung ist in der Gleichung für die zu errechnende Geschwindigkeit V ≤ Wmax x b/l, der Wert

b = d x µ und

d = Lochdurchmesser im Düsenblech (m) und

µ = ein materialabhängiger Faktor der tatsächlichen Streifenausbildung.

The dependencies of these parameters can also be put into a mathematical relationship. It advantageously consists in the fact that the optimal production speed V, i.e. the forward movement of the textile web, depends on the following equation: V <= W Max xb / l where the maximum speed W _max is calculated

W Max = F x A x 2 π and

F = frequency of the reciprocation (1 / s, Hz)

A ∧ = amplitude (m),

b = strip width on the web (m) and

l = strip spacing (m). With even more accurate calculation is in the equation for the speed to be calculated V ≤ W Max xb / l , the value

b = dx µ and

d = hole diameter in the nozzle plate (m) and

µ = a material-dependent factor of the actual streak formation.

Only if these parameters are observed is there a smooth fleece on the impact surface to receive the individual water jets, which in any case when hitting the estate cause a linear depression in the fiber structure.

The swinging movements should be about 0.32 - 30 mm or more in both directions go and a frequency of about 10 - 200 Hz, depending on the forward speed the fiber web. It is with reference to the subject of the invention of Meaning that certain operating parameters are observed. On the one hand Solidification at least on the surface, a surface change can be achieved which is why the hole diameter and water pressure are important. On the other hand mechanical conditions must be observed. The amplitude must not be too high because otherwise the acceleration forces become too high. In any case, the frequency of the Swinging movements that should be higher than specified in the prior art to the to achieve the production speed required in practice.

It is easy to imagine that by this back and forth movement of the jet streams alongside the deep intermingling of the fibers also takes place in the longitudinal and transverse directions. This The type of surface change can be a nonwoven bonding or just one The aim is to smooth the surface. So a hydrodynamic Consolidation plant consist of several needling stations, which are for the Intensive, bilateral solidification of the fleece care, while the last or two last stations with oscillating nozzle bars are provided to alone or additionally smooth the surface for the hardening action. The iridescent bar can against a drum or against an endless belt or it can be hung or hung up Rails be stored.

Fig. 1

in perspektivischer Darstellung eine Draufsicht auf eine längs vorlaufende Faserbahn, mit einem über dieser angeordneten Düsenbalken zur Hydroschlingenverfestigung,

Fig. 2

im Querschnitt der Düsenbalken nach Fig. 1,

Fig. 3

in der Seitenansicht der Düsenbalken nach Fig. 1 mit weiteren Details,

Fig. 4

in der Aufsicht der Düsenbalken nach Fig. 3,

Fig. 5

eine Mikrofotografie mit 16-facher Vergrößerung eines Vlieses, das mit einem stationären Düsenbalken beaufschlagt wurde, und

Fig. 6

eine Mikrofotografie ebenfalls mit 16-facher Vergrößerung der Oberfläche eines Vlieses, wo die Verfestigung mit einem gemäß der Erfindung changierenden Wasserbalken bewirkt wurde.

A device of the type according to the invention is shown as an example in the drawing. Show it:

Fig. 1

a perspective view a plan view of a longitudinally running fiber web, with a nozzle bar arranged above it for hydro-loop strengthening,

Fig. 2

in cross section of the nozzle bar according to FIG. 1,

Fig. 3

1 with further details in the side view of the nozzle bar according to FIG.

Fig. 4

in the supervision of the nozzle bar according to FIG. 3,

Fig. 5

a microphotograph with a 16-fold magnification of a fleece which has been subjected to a stationary nozzle beam, and

Fig. 6

a microphotograph also with a 16-fold enlargement of the surface of a fleece, where the consolidation was effected with a water bar that changes according to the invention.

In Fig. 1, an endless belt 30 is chemically shown, which together with the consolidating fiber web 31 in the direction of arrow 32. Cross with it is with A nozzle bar with the upper part 1 is arranged at a distance above the fiber web 31, the structure of which is shown by way of example in FIG. 2 and described further below. The Nozzle bar is movably suspended from a fixed wall of the housing 39. The attachment to the housing 39 can be done via spring steel. Another example the suspension shows the Fig. 3. Another example could, for. B. a not shown nozzle bar mounted in rails. The from the nozzle slot 13 of the Water jets 33 emerging from the nozzle bar are directed against the fiber web 31 and sweep the width of the fiber web 31. Via a flexible hose 34 on one end of the nozzle bar the necessary water 35 in the nozzle bar. In the middle of the nozzle bar, as shown in FIG. 3, is an electrically driven one Vibrator 36 attached to the beam. This is said to be without affecting a load-bearing Housing the nozzle bar in the direction of the double arrow 37 in short Vibrations are brought with which the water jets 33 more than the Value of their diameter to be moved back and forth laterally. Together with the Forward speed 32 of the fiber web 31 is by means of the back and forth A zigzag pattern of the individual water jets onto the fiber web 31 abandoned, which is inclined so that the forming depressions of the At least touch water jets in their edge areas according to Fig. B). This one here nozzle bar shown alone can at least with another stationary Nozzle bar, which is not shown here, can be added.

As described in detail in patent application DE-A-195 01 738, this exists Housing of the nozzle bar in this example from the upper part 1, which with the lower part 2 is often screwed along the length by the screws 3 from below. The top 1 has two bores 4 and 5, of which the upper the pressure chamber 4 and the lower is the pressure distribution chamber 5. Both chambers are on one end open and screwed again liquid-tight through a cover, not shown. in the The area of the other end face has the pressure chamber 4 through which the pressurized liquid 35 flows through a flexible hose 34. About the The length of the nozzle bar connects a large number of flow bores 9 in an intermediate wall, the two chambers, so that in the pressure chamber 4th inflowing liquid evenly distributed over the length into the pressure distribution chamber 5 emanates. The entering through the flow bores 9 in the pressure distribution chamber 5 Liquid is distributed evenly over the length of the nozzle bar. It serves the volume of the pressure distribution chamber 5 and an impact body 20, which over the length of the Pressure distribution chamber 5 is held exactly between the bores 9 and the slot 10. The impact body 20 is held at a distance from the intermediate wall 8 and on all sides of the Liquid can flow around. To make this possible, the impact body is in the intermediate wall 8 several times over the length of the nozzle bar by means of screws 21 at a distance held. In this way, the liquid comes out of the flow bores 9 first on the impact body 20, is distributed in the distribution chamber 5 and then flows with it same pressure over the length of the beam through the fine holes in the nozzle plate 14. The pressure distribution chamber is open at the bottom, through the compared to the diameter of the bore of the pressure distribution chamber 5 narrow slot 10, which also extends over the length of the bar.

2, the upper part 1 is screwed to the lower part 2 firmly and in a liquid-tight manner. The tightness is brought about by the O-ring 11, which is in an annular groove in the upper part 1 lies in. In the middle between the O-ring 11, the slot 10 encloses one Spring projection 23, which is fitted in a corresponding groove 24 of the lower part 2. In the bottom of the groove 24 of the lower part 2 is again an annular groove in which the O-ring 12 for sealing the nozzle plate 14 is inserted. In a line below the Liquid flow holes 9 and the slot 10 is also in the lower part 2 Slot 13 introduced, which is only very narrow in its upper region and only a little leaves more than the width of the effective nozzle openings of the nozzle plate 14 open.

It is important for the construction of the device that the nozzle bar 1, 2 is mounted in this way is that the reciprocating vibrations 37 and their excitation unit cannot transfer to the rest of the housing of the overall device. That is why Vibrator 40 'and 40' 'hung on the nozzle bar alone and not on the housing supported, and the nozzle bar is via two rubber buffers 41, 42 on the housing 39th stored. The two support arms 43 and 44 are at the two ends of the nozzle bar on the one hand articulated on the nozzle bar and on the other hand on the housing 39 suspended elastically.

The vibrator 40 ', 40' 'is flanged and distributed on both sides of the nozzle bar in such a way that the reciprocating force of the vibrator in the area of Attacks the center of gravity of the nozzle bar. This minimizes all reaction forces of the Movements on the overall case.

1-4, two of the nozzle bars can also be arranged one behind the other be, but their oscillating movements should be in opposite directions. In this way can still existing irregularities in the surface appearance of the Fleece can be compensated.

5 and 6 show micrographs of a fleece. 5 is normal impinged with water jets, so that the nozzle bar has not moved. It the recesses b and the nozzle spacing l can be clearly seen in incident light. The In contrast, Fig. 6 shows a nonwoven with a according to the invention oscillating nozzle bar has been solidified. Even under the microscope no indentations, plastic surface changes are recognized.

Claims (10)

Device with a nozzle bar for generating liquid jets for interlacing the fibers of a textile web, which is moved forward transversely to the nozzle bar by means of a liquid-permeable base, such as a fiber web, which consists of an upper part extending over the working width of the fiber web and a lower part attached to it in a liquid-tight manner, in which Upper part is arranged over its length a pressure chamber, which the pressurized liquid z. B. supplied on the face and a nozzle plate with the holes for the nozzles is liquid-tight on the lower part, characterized in that a) a nozzle bar (1, 2) is mounted so as to be movable longitudinally back and forth solely in the direction perpendicular to the direction of movement (32) of the web (31), b) the nozzle bar (1, 2) for active movement perpendicular to the direction of movement of the web in a force-locking manner with a unit for rapid back and forth movements, such as a vibrator (40 ', 40''), which is connected only to the one nozzle bar (1, 2) set in oscillating movements (37) which change briefly, c) the oscillating movements (37) of the nozzle bar (1, 2) have a frequency of at least 10 Hz with a forward movement of the fiber web (31) of at least 1 m / min, d) the diameter of the nozzle holes is ≤ 0.1 mm, e) the amplitude of the oscillatory movements ≤ 1/2 of the distance (1) of the holes in the nozzle plate (14), but <20 mm, such as. B. at a hole spacing in the nozzle plate (14) of 40 hpi is at least 0.32 mm and f) the water pressure of the water jets is at least 30 bar. Device with a nozzle bar for generating liquid jets for interlacing the fibers of a textile web, which is moved forward transversely to the nozzle bar by means of a liquid-permeable base, such as a fiber web, which consists of an upper part extending over the working width of the fiber web and a lower part attached to it in a liquid-tight manner, in which Upper part is arranged over its length a pressure chamber, which the pressurized liquid z. B. supplied on the face and a nozzle plate with the holes for the nozzles is liquid-tight on the lower part, characterized in that
the production speed V, i.e. the forward movement of the textile web, depends on the following equation: V <= W Max xb / l where the maximum speed W _max is calculated W Max = F x A x 2 π and F = frequency of the reciprocation (1 / s, Hz) A ∧ = amplitude (m), b = strip width on the web (m) and l = strip spacing (m)
is. Apparatus according to claim 2, characterized in that in the equation for the speed to be calculated V ≤ W Max xb / l , the value b = dx µ and d = hole diameter in the nozzle plate (m) and µ = a material-dependent factor of the actual streak formation. Device according to one of the preceding claims, characterized in that that the amplitude of the oscillating movements of the nozzle bar (1, 2) between 0.32 and 30 mm, preferably 5 - 10 mm. Device according to one of the preceding claims, characterized in that that the nozzle bar (1, 2) with a frequency of between 10 - 200 Hz, preferably 50 Hz oscillates. Device according to one of the preceding claims, characterized in that that the reciprocating force, e.g. B. the vibrator (40 ', 40' ') in the area of Center of gravity of the nozzle bar (1, 2) attacks. Device according to claim 6, characterized in that the vibrator (40 ', 40' ') is arranged independently of the housing (39) carrying the device. Device according to claim 7, characterized in that the vibrator (40 ', 40' ') is suspended from the nozzle bar (1, 2) itself. Device according to one of the preceding claims, characterized in that that in a device with several nozzle bars arranged one behind the other with changing fiber web overlay on the respective liquid-permeable Documents only the last or the last two nozzle bars are movably supported and Z. B. are connected to the vibrator. Device according to one of the preceding claims, characterized in that that two nozzle bars, possibly arranged one behind the other in the direction of production, with such a vibrator vibratable and this Swinging movements are in opposite directions.

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