Tetraxial fabric and weaving machine for the manufacture thereof

Claim 2

A tetraxial fabric according to Claim 1, wherein the first (E) and second (F) bias yarns crisscross along two mutually orthogonal directions.

Claim 3

A tetraxial fabric according to either Claim 1 or 2, wherein the first (E) and second (F) bias yarns are set at an angle of 45° to the warp yarns (A,B) and the weft yarns (C,D).

Claim 4

A tetraxial fabric according to any of the preceding claims, wherein the crossovers of all said yarns (A,B,C,D,E,F) occur at common crossover points, at each of which they cross one warp yarn (A;B), one weft yarn (C;D), a first bias yarn (E), and a second bias yarn (F).

Claim 5

A weaving machine for manufacturing the fabric claimed in the preceding claims, comprising means (11,12,13;26,27,28) for guiding the warp yarns (A,B) toward a fabric formation area, and means (36,37) for passing the weft yarns (C,D) through the shed of warp yarns (A,B) in said fabric formation area, and further comprising means (52,53,54) for guiding the bias yarns (E,F) in said fabric formation area such that said bias yarns (E,F) cross each other and the warp (A,B) and weft (C,D) yarns along two different diagonal directions, characterized in that said means for guiding the warp yarns (A,B) comprise a first guide member (11,12,13) for the first course of warp yarns (A) and a second member (26,27,28) guiding the second course of warp yarns (B) in an offset fashion from the first course of warp yarns (A), said first (11,12,13) and second (26,27,28) guide members being provided at juxtaposed locations to each other and being movable each between a rearward position (G;H) where their respective course of warp yarns (A;B) locate to one side relative to the bias yarns (E,F) and the other course of warp yarns and a forward position (G';H') where their respective course of warp yarns (A;B) locate to the opposite side from the bias yarns (E,F) and the other course of warp yarns, between the first course of warp yarns (A) under the guiding action of the first guide member (11,12,13) in the forward position (G') and the second course of warp yarns (B) under the guiding action of the second guide member (26,27,28) in the rearward position (H) there being formed a first shed (W1) for one weft yarn (D), and between the first course of warp yarns (A) under the guiding action of the first guide member (11,12,13) in the rearward position (G) and the second course of warp yarns (B) under the guiding action of the second guide member (26,27,28) in the forward position (H') there being formed a second shed (W2) for another weft yarn (C).

Claim 6

A weaving machine according to Claim 5, wherein each guide member comprises a set of needles (12;27) mounted in a common holder (11;26), each needle (12;27) being formed with a hole (13;28) through which a respective warp yarn (A;B) is passed.

Claim 7

A weaving machine according to Claim 6, wherein said holder (11;26) of the needles (12;27) is reciprocated rotatively to move the warp yarns (A;B) between said rearward position (G:H) and said forward position (G';H').

Claim 8

A weaving machine according to either Claim 5 or 7, wherein said means for guiding the bias yarns comprise a set of guide elements (52) entrained of stepwise motion around an endless path, each guide element (52) being provided with an eyelet (54) through which a respective bias yarn (E,F) is passed.

Claim 9

A weaving machine according to Claim 8, wherein said guide elements (52) are attached to a chain (53) driven around said endless path.

Claim 10

A weaving machine according to Claim 8, wherein at the location of said guide elements (52) there is provided a carousel (63) to entrain in motion, in timed relationship with the movement of the guide elements (52), a plurality of yarn storing devices (64) from each of which one or more yarns extend which are passed through the eyelets (54) in the respective guide elements (52).

Claim 11

A weaving machine according to Claim 10, wherein the guide elements (52) are entrained in motion around an elongate endless path with two straight sections and two circular arc sections interconnecting the two straight sections, and wherein the carousel (63) entrains in motion the yarn storing devices (64) around a substantially lozenge-like path, with the acute angles of the lozenge being located at said circular arc sections.

Claim 12

A weaving machine according to Claim 5, comprising two insertion members for the weft yarns (36,37), each at a respective one of said two sheds (W1,W2) that form between the warp yarns (A,B).

Claim 13

A weaving machine according to Claim 8, comprising timing means (21,22,38,39,77) which control sequentially, for each weaving cycle: the first guide member (11,12,13) to move to the forward position (G') and the second guide member (26,27,28) to be held in the rearward position (H) to form the first shed (W1) through the warp yarns (A,B); a weft yarn (D) to be inserted through the first shed (W1); the first guide member (11,12,13) to move to the rearward position (G); the guide elements (52,54) for the bias yarns (E,F) to move forward one step; the second guide member (26,27,28) to move to the forward position (H') and the first guide member (11,12,13) to be held in the rearward position (G) to form the second shed (W2) through the warp yarns (A,B); another weft yarn (C) to be inserted through the second shed (W2); the second guide member (26,27,28) to be moved to the rearward position (H); and the guide elements (52,54) for the bias yarns to be moved forward one step.

Claim 14

A weaving machine according to Claim 5, wherein each guide member comprises a set of guide tubes (101;104) rigidly carried by a set of respective plates (102;105) parallel one to the other and mounted on a common holder (103;106), through each guide tube (101;104) being passed a respective warp yarn (A;B).

Claim 15

A weaving machine according to Claim 14, wherein said holder (103;106) of the plates (102;105) is reciprocated rotatively along an axis (X) corresponding to the starting position (Z) of the formed fabric (T), to move the warp yarns (A;B) between said rearward position and said forward position.

Claim 16

A weaving machine according to Claim 15, wherein the plates (102;105) have each a notch (107;108), all the notches (107,108) being aligned to form a passage for the means (136;137) for passing the weft yarns (C;D) when the plates (102,105) of the two set of plates are in a position corresponding to the formation of the first shed or the second shed.

Claim 17

A weaving machine according to either Claim 5 or 16, wherein said means for guiding the bias yarns comprise a set of guide tubes (194) entrained of stepwise motion around an endless path, through each guide tube (194) being passed a respective bias yarn (E,F).

Claim 18

A weaving machine according to claim 17, wherein said guide tubes (194) are attached to a cogged belt (193) driven around said endless path.

Claim 19

A weaving machine according to claim 17, wherein at the location of said guide tubes (194) there is provided a carousel (163) to entrain in motion, in timed relationship with the movement of the guide tubes (194), a plurality of yarn storing devices (164) from which one or more yarns extend which are passed through the respective guide tubes (194).

Claim 20

A weaving machine according to either Claim 10 or 19, wherein the carousel (63;163) is moved rotatably about its axis.

Claim 21

A weaving machine according to claim 7, wherein two reeds (78,79) are provided which are rotatively reciprocated, each reed (78;79), once a respective weft yarn (C;D) is inserted, holding a respective course of warp yarns (A;B) separated and urging said weft yarn (C;D) close against the previously formed fabric (T).

Claim 22

A weaving machine according to claim 16, wherein two set of plates (185,186) are provided, mounted on two respective common holders (187,188) rotatively reciprocated, each set of plates (185;186), once a respective weft yarn (C;D) is inserted, holding a respective course of warp yarns (A;B) separated and urging said weft yarn (C;D) close against the previously formed fabric (T).