Plant and Method for Making Continuous Elastic Yarns Made of Silicon Material and Continuous Elastic Yarn Made of Silicon Material Thus Obtained

• US 20110200821A1
• Filed: 10/20/2009
• Published: 08/18/2011
• Est. Priority Date: 10/21/2008
• Status: Active Grant

• Current Assignee: Lemur S.p.a.
• Original Assignee: Lemur S.p.a.
• Inventors: Klotz, Thomas
• Granted Patent: US 9,481,113 B2
• Time in Patent Office: Days
• US Class Current: 428/401
• CPC Class Codes: B29C 2035/0827 using UV radiation
• CPC Class Codes: B29C 2035/0855 using microwave
• CPC Class Codes: B29C 35/02 Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mouldcold vulcanisation B29C35/18 ; vulcanising tyres, presses therefor B29D30/0601
• CPC Class Codes: B29C 35/0277 Apparatus with continuous transport of the material to be cured B29C35/025, B29C35/06, B29C35/10, B29C35/14 take precedence
• CPC Class Codes: B29C 35/10 for articles of indefinite length
• CPC Class Codes: B29C 48/0018 combined with shaping by orienting, stretching or shrinking, e.g. film blowing B29C48/0017 takes precedence
• CPC Class Codes: B29C 48/022 characterised by the choice of material
• CPC Class Codes: B29C 48/05 Filamentary, e.g. strands
• CPC Class Codes: B29C 48/154 Coating solid articles, i.e. non-hollow articles
• CPC Class Codes: B29C 48/25 Component parts, details or accessories; Auxiliary operations
• CPC Class Codes: B29C 48/286 Raw material dosing
• CPC Class Codes: B29C 48/34 Cross-head annular extrusion nozzles, i.e. for simultaneously receiving moulding material and the preform to be coated
• CPC Class Codes: B29C 48/355 Conveyors for extruded articles
• CPC Class Codes: B29C 48/37 Gear pumps
• CPC Class Codes: B29C 48/387 using a screw extruder and a gear pump
• CPC Class Codes: B29C 48/395 using screws surrounded by a cooperating barrel, e.g. single screw extruders
• CPC Class Codes: B29C 48/69 Filters or screens for the moulding material
• CPC Class Codes: B29C 48/693 Substantially flat filters mounted at the end of an extruder screw perpendicular to the feed axis
• CPC Class Codes: B29C 48/83 Heating or cooling the cylinders
• CPC Class Codes: B29C 48/832 Heating
• CPC Class Codes: B29C 48/834 : Cooling
• CPC Class Codes: B29C 48/91 : Heating, e.g. for cross linking
• CPC Class Codes: B29K 2083/00 : Use of polymers having silicon, with or without sulfur, nitrogen, oxygen, or carbon only, in the main chain, as moulding material
• CPC Class Codes: B29K 2083/005 : LSR, i.e. liquid silicone rubbers, or derivatives thereof
• CPC Class Codes: B29K 2301/10 : Thermosetting resins
• CPC Class Codes: B29K 2995/0046 : Elastic
• CPC Class Codes: B29L 2031/707 : Cables, i.e. two or more filaments combined together, e.g. ropes, cords, strings, yarns filamentary material B29L2031/731, electric cables B29L2031/3462, optical cables B29L2011/0075
• CPC Class Codes: B29L 2031/731 : Filamentary material, i.e. comprised of a single element, e.g. filaments, strands, threads, fibres cables B29L2031/707
• CPC Class Codes: D01D 13/02 : Elements of machines in combination
• CPC Class Codes: D01D 5/084 : Heating filaments, threads or the like, leaving the spinnerettes
• CPC Class Codes: D01D 5/088 : Cooling filaments, threads or the like, leaving the spinnerettes
• CPC Class Codes: D01D 5/092 : in shafts or chimneys
• CPC Class Codes: D01D 5/098 : with simultaneous stretching
• CPC Class Codes: D01D 5/16 : using rollers, or like mechanical devices, e.g. snubbing pins
• CPC Class Codes: D01F 11/08 : of macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: D01F 6/76 : from other polycondensation products
• CPC Class Codes: D01F 6/96 : from other synthetic polymers
• CPC Class Codes: Y10T 428/298 : Physical dimension

Abstract

A plant for making continuous yarns (30) made of silicon material comprises at least an extrusion station (12), into which the material is introduced in an amorphous condition, and extrusion means (15) which cause the material to exit from the extrusion station (12) along an extrusion axis (D). The plant also comprises a vulcanization station (16), located downstream of the extrusion station (12), at a determinate distance (“L”) therefrom, in which the continuous yarn (30) is vulcanized in a direction of treatment (T). The plant also comprises a drawing unit (18), disposed downstream of the vulcanization station (16).

Claims

1. Plant for making continuous yarns (30) made of silicon material, comprising at least an extrusion station (12), provided with an extrusion body (31) into which said material is able to be introduced in an amorphous condition, and extrusion means (15) able to allow said material to exit from said extrusion station (12) along an extrusion axis (D), and a vulcanization station (16), located downstream of said extrusion station (12), at a determinate distance (“

L”

) therefrom, characterized in that;

said extrusion means (15) are disposed so that the extrusion axis (D) is substantially vertical,

the plant also comprises a drawing unit (18), disposed downstream of said vulcanization station (16), and able to impart on the elastic yarn (30) exiting from the extrusion station (12) a drawing value in a ratio comprised between 2 and 6 before it enters the vulcanization station (16), and hence at least along said distance (“

L”

),

wherein said distance (“

L”

) is adjustable to vary the drawing conditions of the elastic yarn (30) and to obtain a final yarn (30) with a thickness at least less than 0.7 mm, advantageously in the range of 0.4-0.3 mm and less, and having the desired orientation of the molecular chains.

2. Plant as in claim 1, characterized in that, in said vulcanization station (16), said extruded product (30) is vulcanized along a processing direction parallel or coincident to the extrusion axis (D).

3. Plant as in claim 1 or 2, characterized in that said vulcanization station (16) is selectively movable with respect to said extrusion station (12) so as to vary said distance (“

L”

) at least according to the desired value of final thickness to be conferred on the elastic yarn (30).

4. Plant as in claim 3, characterized in that said distance (“

L”

) is variable between 400 and 1500 mm.

5. Plant as in any claim hereinbefore, characterized in that said extrusion body (31) has a vertical elbow shape.

6. Plant as in any claim hereinbefore, comprising a collection unit (26), located downstream of the vulcanization station (16) and able to collect the extruded product (30), characterized in that said collection unit (26) comprises said drawing unit (18).

7. Plant as in any claim hereinbefore, characterized in that it comprises a controlled cooling station (17), located downstream of the vulcanization station (16) and upstream of the collection unit (26).

8. Plant as in any claim hereinbefore, characterized in that the extrusion station (12) comprises a heating and cooling device (24) for the heat regulation of the extrusion station (12).

9. Plant as in any claim hereinbefore, characterized in that the vulcanization station (16) comprises a zonal vulcanization oven (27).

10. Elastic yarn made of silicon material, made in a plant as in any claim hereinbefore, with a diameter in the range of 0.3-0.4 mm and less, to 0.1 mm, with a number of filaments comprised between 2 and 30.

11. Method to make elastic yarns (30) of silicon material, comprising at least an extrusion step, wherein by means of an extrusion station (12) comprising extrusion means (15) said material is made to exit along an extrusion axis (D), with a conditioned shaping, and at least a vulcanization station step carried out in a vulcanization oven (27) disposed downstream of said extrusion means (15), characterized in that:

in said extrusion step, said extrusion means (15) confer on the extrusion axis (D) a substantially vertical direction,

in the segment (“

L”

) between the exit from the extrusion means (15) and the entrance into the vulcanization oven the elastic yarn (30) is subjected to a drawing action performed by a drawing unit (18) disposed downstream of said vulcanization oven (27), in which the drawing ratio conferred on the elastic yarn (30) before entering the vulcanization oven (27) is comprised in a value between 2 and 6 and in which the elastic yarn (30) has a final thickness of less than 0.7 mm, advantageously in the range of 0.4-0.3 mm, to 0.1 mm