The present invention relates to a water-jet beam for treating a textile web. More particularly this invention concerns a suction apparatus or chamber for such a beam.
In the manufacture of a textile web workpiece, e.g. woven, knitted, or nonwoven textile including felts and fleeces made of staple fibers, continuous filaments or cellulose fibers and even having multiple layers it is standard to use a water-jet treatment. Such textiles are typically treated by passing them over a support and directing high-pressure liquid jets at them from an overhead jet beam. A perforated suction surface provided below the jet beam aspirates the spray. A so-called suction chamber is provided between the jet beam and the workpiece to aspirate spray created by the process.
It is known from U.S. Pat. No. 6,457,335 to collect the liquid spraying against the water beam. Here the suction apparatus is located to the side of the water beam and extends along its entire length. A funnel-shaped slot formed at the edge of the water beam has a slot width of approximately 2 mm at its inner end. If a sufficiently strong vacuum is connected to the otherwise completely enclosed apparatus, all the droplets including any spray mist from the underside of the water beam can be aspirated safely from the goods being needled.
A water beam for the water needling of textiles is further known from WO 2001/040562 of Vuillaume that has a suction chamber attached to the water beam in an upper region and forming a groove adjacent the water jets, with a porous floor adjacent this groove. Thus spray is aspirated both through the groove and through the porous floor. Spray can only inadequately be removed with this apparatus. Furthermore, spray cannot be aspirated on the opposite side of the water jet.
It is therefore an object of the present invention to provide an improved suction apparatus for a textile-treatment water-jet beam.
Another object is the provision of such an improved suction apparatus for textile-treatment water-jet beam that overcomes the above-given disadvantages, in particular that prevents the formation of droplets on the water beam commonly encountered until now.
A suction apparatus for an elongated water beam that extends transversely to and directs a liquid jet at a longitudinally passing textile web. The apparatus has according to the invention a suction chamber extending transversely of the web adjacent the jet and having a perforated lower wall, means for withdrawing air from inside the chamber and thereby aspirating spray from adjacent the jet through the perforated lower wall, and an air-displacement body inside the suction chamber oriented for generally uniform suction across the perforated lower wall. Thus uniform suction effect is guaranteed across the entire width and/or length of the perforated suction surface formed by the lower wall.
By providing the air-displacement body, air flow inside the suction chamber is adjusted as needed. Particular flexibility is achieved when the air-displacement body is adjustably mounted with respect to height and angle.
In this way, a substantially drip-free water beam is guaranteed across the entire width in a simple and cost-efficient manner, preventing drops from dripping onto the textile web, whether woven, knitted, or felted, which droplets may result in pollution and/or damage. The spray water and the water mist produced by the spraying action are collected with uniform suction power across the entire surface of a suction device, thus preventing the formation of drops on the water beam commonly encountered until now.
It is advantageous if the air-displacement body is located above the perforated suction surface, and in particular s above the portion of the suction surface having a relatively large open portion, and if it -constricts the perforated suction surface such that a maximum air current of, for example, 2 m/s is achieved on the outside of the perforated suction surface.
In a further embodiment of the invention, it is advantageous that the air-displacement body extends substantially across the entire width and/or length of the suction chamber and that the air-displacement body is a substantially rectangular element, particularly a box that extends at an angle in the direction of the suction chamber.
It is also advantageous when the air-displacement body has an lower surface that forms an angle ranging between 1° and 30°, particularly between 1° and 5°, in the longitudinal direction of the suction chamber with the lower wall thereof, the gap between the air-displacement body and the perforated suction surfaces becoming narrower away from the outlet port through which air is sucked from the chamber.
The air-displacement body according to the invention ends short of one end lateral wall of the chamber having the suction outlet. Since the gap between the air-displacement body and the perforated suction surface becomes narrower in the direction of the suction device, a varying suction effect can be prevented by one-ended suction.
Furthermore, it is advantageous that the suction surface be disposed at an angle and extends from an upper region adjacent the water beam and/or a drip edge to a lower region of the suction chamber. The spray water is discharged particularly effectively because it flows down along the inclined suction surface of the suction chamber water due to gravity and goes in the direction of the lower region of the suction surface and thus moves away from the water jet. For this purpose, the region of the suction chamber facing the water beam may also be configured without a drip edge.
To this end the perforated suction surface has orifices with varying cross-sectional surfaces. As a result, uniform suction pressure is guaranteed across the entire suction surface of the suction device. Starting from the drip edge downward, the cross-sectional surfaces of the orifices become increasingly larger. Alternately, starting from the drip edge, the cross-sectional surface, that is the total flow cross section, of the orifices becomes larger either continuously or in steps. It is also advantageous when the distance between the individual orifices is the same or different.
Furthermore, an angle is formed by a tangential line of a screen roller supporting the web and the perforated suction surface ranges between 5° and 25°, particularly between 6° and 15°, the orifices of the suction surfaces on the inner side facing a water beam constituting an open surface or flow cross section of approximately 3% to 8%, preferably 5%, and on the exterior side of approximately 10% to 25%, preferably 20% of the total surface area of the lower wall. Consequently, a stronger air current is achieved on the outer edge region of the suction surface than on the inner edge. The water drops migrating to the lower and hence outer region of the suction surface as a result of gravity are then suctioned into the interior of the suction chamber via the large orifices.
In a further embodiment of the invention, it is advantageous that an air feed device is associated with the water beam and/or the suction chamber, the device being provided with at least one outlet opening in the region of the water beam. In this way, the water jet is supplied with an additional and independent dry air current. In this process, the suction effect of the water jet traveling at up to 200 m/s is utilized. This jet no longer takes in the moist ambient air enriched with spray mist, but instead the dry air provided via the air feed device. As a result, the deflection of the water jet caused by minute water droplets in the air can be suppressed.
Furthermore, the air feed device has an air feed passage having a width measured parallel to the web-travel direction of 1 to 15 mm, preferably 3 to 10 mm and particularly 3 to 6 mm between an exterior side of the water stream and an exterior side of the suction chamber facing the water stream. In this particularly simple configuration of the air feed device, the air feed passage is formed by an air gap between the water beam and the suction chamber. For this, substantially no further component are required. The air feed passage, however, may also be formed by installed hoses.
In an advantageous embodiment of the air feed device, the air supply to the water jet can be such that the air feed device is associated with a fan to generate a slight overpressure. In this way, the dry air is actively supplied to the water jet and the air supply to the water jet does not take place exclusively by means of the suction effect of the water jet described above, but additionally by a small overpressure inside the air feed passage.
According to a further characteristic of the invention, the outlet opening of the air feed device extends substantially across the entire length of the water beam. In this way, it is guaranteed in a simple manner that the water jet is supplied with dry air across the entire length of the water beam and is not influenced by fine water droplets or spray mist.
In a further embodiment of the invention, it is advantageous that the outlet opening of the air feed device is oriented such that the air current strikes the water jet exiting from the water beam in a substantially perpendicular manner. In this way, the exiting water jet is focused in a simple manner and the spray water is directed towards the water beam.
It is furthermore advantageous that the air feed device or the air gap is provided at least in part between the water beam and the outlet opening of the suction chamber or that it is guided along the outside of the water beam and extends parallel to the same in the region of an underside of the water beam. The exiting water jet is focused with the help of the dry air current exiting from the air feed device in the region of the underside of the water beam. The guided air current is protected from spray water until the current exits since the air feed passage is delimited downward by the suction chamber.
According to a further development of the invention, it is also possible to dispose the suction chamber and/or the air feed device symmetrically on both sides of the water beam or the water jet. Spray water bouncing the textile web can thus be drawn off in the advancing direction of the textile after the water jet has made contact or optionally, as needed, also before contact with the water jet. Likewise, the independent supply of dry air may be carried out via the air feed device either upstream or downstream of the water jet. The configurations of the suction chamber as well as of the air feed device may be done independently of each other in arbitrary combinations. In this way, it is ensured that the spray water can be completely removed on both sides of the water jet, if necessary.
It is also advantageous that the orifices of the perforated suction surface on the interior side facing the water jet are preferably configured as parallel slots measuring between 1 mm and 10 mm in length and between 0.1 mm and 3 mm in width, the orifices provided on the exterior side of the perforated suction surface being preferably configured in an angle shape having a length between 1 mm and 10 mm and a width between 0.1 mm and 3 mm.
It is particularly advantageous when the orifices have cross-sectional surfaces with different shapes and are configured as oval, polygonal, angle-shaped or as elongated slots. Such a configuration and shape of the orifices guarantees that the drops are forced in the direction of the lower region of the suction surface as they migrate along the surface, pass the orifices and cannot easily bypass them. The angled orifices of the perforated suction surface in the region having a relatively large open surface are particularly effective for this process.
The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:
As seen in
Adjacent the water beam la is a suction apparatus or suction chamber 5a which has a sloping perforated suction surface 3a, provided with openings 3c on its lower wall 5b so that the spray formed when the water jet 10 impinges on the textile workpiece 2 is pulled to the lower wall of the suction chamber 5b and is then completely sucked from the suction chamber 5a. Water droplets thus do not collect on the lower face of the water beam la and no longer drip onto the workpiece 2.
In this embodiment two such suction chambers 5a are arranged symmetrically on both sides of the water beam 1a, upstream and downstream relative to a workpiece travel direction D. A vacuum is created in the suction chamber 5a by a pump 15 (
The openings 3c in the perforated suction surface have a smaller area or flow cross-section in the region 3a than the openings 3c in the region 3b. In this way, an approximately uniform suction pressure is generated on the inner upper side of the suction surface 3a or 3b so that spray impinging upon the textile workpiece 2 can easily be removed by suction. Water droplets flowing downward along the lower face of the floor 5b as a result of gravity can be sucked completely into the suction chamber 5a through the larger openings 3c in the lower area of the suction surface 6c.
The distance between the individual openings 3c can be the same or different. The cross-sectional areas of the openings 3c increase moving away from the drip edge 6a toward the suction chamber 5a or an outer wall 5c of the suction chamber 5a remote from the water beam la. To achieve this effect the cross-sectional areas of the openings 3c beginning from the drip edge 6a can become increasingly larger continuously or in uniform steps.
As can be seen from the second embodiment in
According to
Dry air passing through the air-supply passage 11b of the air supply apparatus 11a to the water jet 10 has the advantage that it does not influence the movement of the water jet 10. The water jet 10 is thus not influenced by very fine water droplets or mist and can in particular be projected onto the textile workpiece 2 in a focused manner. In this embodiment according to
In
The cross-sectional surface of the air feed device 11a or air feed passage 11b ranges between 3 and 15 mm, preferably between 5 and 10 mm, particularly between 7 and 8 mm.
The width of the air-supply passage 11b is between 3 and 15 mm, preferably between 5 and 10 mm, especially between 7 and 8 mm. In this embodiment, the air-supply passage 11b of the air supply apparatus 11a is of a width of 1 to 15 mm, preferably 3 to 10 mm, and especially 3 and 6 mm between an outer face of the water beam 1c and the confronting outer face of the wall 5d of the suction chamber 5a facing the water beam 1a. In an embodiment not shown in the drawings, the air-supply passage 11b can also be formed by hoses or similar air supply apparatus.
The outlet opening 11c extends approximately over the entire length of the water beam 1a. The outlet opening 11c is further aligned so that the air jet emerging from it impinges approximately horizontally and perpendicularly on the vertical water jet 10 emerging from the water beam 1a.
According to
According to a further embodiment as shown in
The air-displacement body 7a advantageously extends over the entire length of the suction chamber 5a. In order to achieve the greatest possible flexibility in adjusting the air flows inside the suction chamber 5a, in a further advantageous embodiment not shown in the drawings the air-displacement body 7a can be mounted so that its height and inclination can be varied.
As can be seen from
As can be seen from
Number | Date | Country | Kind |
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102006030803 | Jun 2006 | DE | national |