Claims
- 1. A method of forming reinforcing fibers for castable matrix materials, said fibers of material capable of being permanently deformed or shaped, said process comprising the steps of shaping a strip of said material having a width greater than 1/4 inch through a roll forming operation wherein the edges of the strip are enlarged, and thereafter shearing the strip transversely to produce a reinforcing fiber of the desired width having enlarged ends.
- 2. Method according to claim 1, wherein said roll forming operations fold the edges of said strip over onto the surface of the strip.
- 3. Method according to claim 2, wherein the thickness of the folded edges are between about two and four times the thickness of the strip.
- 4. Method according to claim 2, wherein said roll forming operations include the following steps
- a. turning the edge portions of the strip through about 90.degree.;
- b. thereafter turning the edge portions through a further acute angle towards the strip, and
- c. thereafter flattening said edge portions onto the strip.
- 5. Method according to claim 2, wherein a plurality of narrow strips are obtained from a wider strip by means of a strip slitting operation, said roll forming operations being performed on said narrow strips while they run side by side, said roll forming operations including:
- a. guiding the strips into a first roll forming stage in which the edge portions are bent through about 45.degree.;
- b. thereafter bending the edge portions through a further 45.degree. to 90.degree.;
- c. thereafter bending the strip at positions inwardly of the edge portions, through about 45.degree.;
- d. thereafter bending said edge portions through a further 45.degree., and
- e. thereafter flattening the bend introduced by operation (c) to place the edge portions into contact or close parallel proximity with the strip.
- 6. Method according to claim 5, wherein, in order to facilitate guidance of said strips, a small false bend is introduced into the centre of said strip to space their edges sufficiently to allow insertion of or positive guide means therebetween.
- 7. Method according to claim 1, wherein said roll forming operations include the application of a rolling force perpendicularly to the edge of the strip while said strip is generally constrained except at its edge portions, said edge portions being deformed to thereby enlarge same.
- 8. Method according to claim 7, wherein said enlarged edge portions have oppositely directed projections of rounded transverse cross-sectional elevation.
- 9. Method according to claim 7, wherein a plurality of narrow strips are obtained from a wider strip by means of a strip slitting operation, said strips being separated in a direction transverse to the direction of travel thereof prior to said edge rolling operation.
- 10. A method according to claim 7, wherein a plurality of narrow strips are obtained from a wider strip by means of a strip slitting operation, said strips being rerolled and subsequently individually fed through said edge rolling operation.
- 11. An apparatus for forming reinforcing fibers for castable matrix materials wherein said fibers include a shank portion of substantially uniform generally rectangular cross-sectional area, and enlarged end portions having cross-sectional areas at least about 1.5 times larger than the cross-sectional area of the shank, said apparatus comprising means for splitting a relatively wide sheet of reinforcing material along its longitudinal direction to form a plurality of narrow strips of reinforcing material; means for feeding said strips of reinforcing material simultaneously into an edge forming means, said edge forming means including means receiving said strips of reinforcing material for bending the edges of said strips at right angles, means for further bending said edges to form an acute angle with respect to the plane of said strips, and means for flattening said turned edges of said strips back onto said strips; and means for cutting said strips into narrow fibers having an average width of about 0.010 to about 0.06 inch.
- 12. The apparatus of claim 11 wherein said means for feeding said strips simultaneously into said edge forming means comprises means for spacing the edges of said strips along the plane of the strips before the edges are formed by said edge forming means.
- 13. Apparatus for forming reinforcing fibers for castable matrix materials wherein said fibers include a shank portion of substantially uniform generally rectangular cross-sectional area, and enlarged end portions having cross-sectional areas of at least about 1.5 times larger than the cross-sectional area of the shank, said apparatus comprising means for feeding at least one strip of reinforcing material into an edge forming means, said strip having an average width of about 1/4 to about 5 inches, said edge forming means including means for constraining the strip such that only a selected portion of each edge of the strip extends outwardly and away from the constraining means, and means for deforming said extending edge portions of said strip to form an enlarged edge portion having a cross-sectional area of at least 1.5 times larger than the cross-sectional area of said constrained portion of said strip; means for cutting said strip into narrow fibers having an average width of about 0.010 to about 0.06 inch and an average length of about 1/4 to about 5 inches.
- 14. The apparatus of claim 13 wherein said means for deforming said extending portions of said strip includes means for forming enlarged end portions, each end portion having at least two surfaces of generally parabolic shape.
- 15. The apparatus of claim 13 further comprising means for splitting a relatively wide sheet of reinforcing material along its longitudinal direction to form a plurality of narrow strips of reinforcing material, a plurality of said edge forming means, and means for feeding said strips into said plurality of edge forming means, said feeding means including means for spacing the edges of said strips with respect to one another.
- 16. An apparatus for forming reinforcing fibers for castable matrix materials wherein said fibers include a shank portion of substantially uniform generally rectangular cross-sectional area and enlarged end portions having cross-sectional areas of at least about 1.5 times larger than the cross-sectional area of the shank, said apparatus comprising means for feeding at least one strip of reinforcing material into an edge forming means, said strip having an average width of about 1/4 to 5 inches, said edge forming means including means for bending the edges of said strip at right angles, means for bending said edge to form an acute angle with respect to the plane of said strip, and means for flattening said turned edges of said strip back onto said strip; and means for cutting said strip into narrow fibers having an average width of about 0.010 to about 0.06 inch.
Priority Claims (1)
Number |
Date |
Country |
Kind |
1402/72 |
Nov 1972 |
AU |
|
FIELD OF THE INVENTION
This is a division of application Ser. No. 419,446 filed Nov. 27, 1973, now U.S. Pat. No. 3,953,953.
US Referenced Citations (4)
Divisions (1)
|
Number |
Date |
Country |
Parent |
419446 |
Nov 1973 |
|