A finishing machine with pneumatic entrainment of fabric in strand form

Abstract: A machine (10) for finishing fabrics in strand form, comprising a container (14) and at least an entrainment pipe (24) associated with means for producing an air flow for entraining a strand of fabric (12). The entrainment pipe (24) has a terminal portion (34) which ends tangential to the bottom wall (20) of the container (14) and is provided with a cross-section progressively increasing in the direction of entrainment of the fabric (12).

Description: The present invention relates to a machine for finishing fabrics in strand form, of the type known, for example, from US-A-3780544 and US-A-3921420 in the name of Gaston County Dyeing Machine Co., which show machines for treatment of fabrics provided with a container having a bottom wall on which the fabric to be treated collects on a series of movable laps. The fabric in strand form is moved within the container by means of an entrainment pipe associated with means for producing an entrainment air flow adapted to continuously move the fabric. EP-A-629732 shows a device having the features of the preamble of claim 1. This known device comprises: a bowl and a J-shaped basket, in which the wet material accumulates and advances; a closed circuit for discharging and recycling the treatment fluid; a jet for impregnating and driving the material in movement by means of the treatment liquid itself; a means for depositing the impregnated material in the branch of the J which forms the entrance of the basket. Between the exit of the basket and the entrance of the jet, it also comprises a pneumatic means intended for previously spreading this material and, after the exit of the jet, it comprises a deflector intended for deflecting the material to the entrance of the basket. EP-A-300359 discloses a process and apparatus for the wet treatment of textile material with an aqueous liquor that contains dyestuff or other textile processing products. Textile material in continuous loop form is recirculated in a jet dyeing machine, and a recirculating gas stream propels the material. A blower recirculates the gas stream while aqueous liquor is metered into the stream by aspirating the liquor at the upstream side of the blower. The action of the blower finely disperses the liquor within the gas stream. Many fabrics, especially the finest and more delicate ones, show a marked tendence to the formation of signes or marks during finishing treatments carried out on the fabric in strand form. These defects seem to be essentially due to the fact that the bends which form when the fabric is collected in a strand remain in certain position for an extended time during the treatment, thereby exposing the fabric on the top of the bends more than other parts of the fabric to abrasions, compressions, rubbings, etc. The object of the present invention is to provide a finishing machine of an improved type which overcomes or at least reduces said drawbacks. In accordance with the present invention, this object is achieved by a machine having the features forming the subject of claim 1. Further characteristics and advantages of the present invention will become clear in the course of the detailed description which follows, given purely by way of non-limiting example, with reference to the annexed drawings, wherein: figure 1 is a schematic lateral view of a machine according to the invention, and figure 2 is a schematic perspective view of the part indicated by arrow II in figure 1. With reference to the drawings, 10 indicates a machine intended to carry out finishing treatments on one or more pieces of fabric 12 in strand form. The machine comprises a closed container 14 having a front section 16 and a rear section 18. The container 14 has a bottom wall 20 which has an arcuate shape in correspondence with the rear section 18. In the front section 16 of the container 14 there is placed a motor-driven cylinder 22 which raises the strand of fabric 12 from the bottom of the container and supplies the strand to a pneumatic entrainment pipe 24. The raising cylinder 22 can be associated to a blower 26 which produces a laminar air flow tangent to the surface of the cylinder 22, having the purpose to move the strand and change the position of the bends. The machine 10 is generally arranged for operating at the same time with two or more strands of fabric arranged parallel to each other in a direction orthogonal to the plane of representation of figure 1. Whereas the raising cylinder 22 can be the same for all the strands of fabric, each strand 12 is associated with an individual entrainment pipe 24. In the following it will be described in detail the structure of only one of said entrainment pipes, being intended that the other pipes are identical and disposed parallel to the first. The entrainment pipe 24 has a central portion 28 formed by a metallic tube with a circular cross-sectional area slightly increasing in the direction of entrainment of the fabric. A first end of the central portion 28 is connected to a strand feeding section 30 wherein an entrainment air flow is conveyed by means of a series of distribution pipes 32, the air flow coming from a blower (not shown) placed outside the machine. A second end of the central portion 28 is joined to an elbow terminal portion 34 which is radiused to the arcuate parts of the bottom wall 20 of the container 14. The terminal portion 34 has a cross-sectional which progressively increases in the direction of movement of the strand of fabric. In this way, the air flow which entrains the strand 12 expands rapidly in the terminal portion 34, causing an opening of the strand with a consequent variation of the position of the bends. In order to promote this opening movement, on the lateral walls of the terminal portion 34 there are provided a plurality of perforations 36 which have the purpose to partially discharge air to the outside, which increases the depression effect within the terminal portion 34. Outside the terminal portion 34, the strand of fabric collects in a series of laps on the bottom wall 20. The radiused portion 34 brings smoothly the strand against the arcuate wall 20 and avoids strikes or severe mechanical actions against the walls of the machine. For simplicity of construction, the terminal portion 34 may have a cross-section with a quadrangular shape, with external and internal arcuate walls constituted by sectors of sheet metal welded to each other.

Claims: A machine for finishing of fabrics in strand form, comprising: a container (14) having a bottom wall (20) on which the fabric to be treated collects in a series of movable laps, and at least one fabric entrainment pipe (24) associated with means for producing an entrainment air flow and adapted to continuously move the fabric towards the bottom wall of the container (14), the entrainment pipe (24) having a terminal portion (34) radiused to the bottom wall (20) of the container (14) and provided with a cross-sectional area progressively increasing in the direction of entrainment of the fabric, characterized in that said terminal portion (34) of the entrainment pipe (24) is provided with a plurality of perforations (36) adapted to produce a partial expulsion of the air flow. A machine according to claim 1, characterized in that the entrainment pipe (24) has a central portion (28) with a rectilinear axis and having a cross-sectional area progressively increasing toward said terminal portion (34).

Inventors: BOZZO GIOVANNI, BOZZO, GIOVANNI
Applicants: FLAINOX SRL, FLAINOX S.R.L.
Application year: 1997
Main classification: D06B3
IPC codes: D06B3