Compagnie Generale Des Etablissements Michelin

Compagnie Generale Des Etablissments Michelin

Stephane Laurent

Alexandre Gianetti

Marianna Chevalley

Romain Barbat

Emmanuel Clement

Benoît Renaux

A multi-strand cord () comprises an internal layer (CI) of the cord made up of K=1 three-layer (C1, C2, C3) internal strand (TI), with the internal layer (C1) being made up of Q internal metallic threads (F1), the intermediate layer (C2) being made up of M intermediate metallic threads (F2) and the external layer (C3) being made up of N external metallic threads (F3), and an external layer (CE) of the cord made up of L>1 three-layer (C1', C2′, C3′) external strands (TE) wound around the internal layer (CI) of the cord, with the internal layer (C1′) being made up of Q′ internal metallic threads (F1′), the intermediate layer (C2′) being made up of M′ intermediate metallic threads (F2′) and the external layer (C3′) being made up of N′ external metallic threads (F3′). The cord () has an endurance criterion SL≤40 000 MPa·mm with and a size criterion Ec≥0.46 with Ec=Sc/Se.

Double-layer multi-strand cable having improved bending endurance

A multi-strand cord () comprises an internal layer (CI) of the cord made up of K=1 two-layer (C, C) internal strand (TI), with the internal layer (C) being made up of Q internal metallic threads (F), and the external layer (C) being made up of N external metallic threads (F), and an external layer (CE) of the cord made up of L>1 two-layer (C', C′) external strands (TE) wound around the internal layer (CI) of the cord, with the internal layer (C′) being made up of Q′ internal metallic threads (F′), and the external layer (C′) being made up of N′ external metallic threads (F′). The cord () has an endurance criterion SL≤40 000 MPa·mm with and a size criterion Ec≥0.46 with Ec=Sc/Se.

A multi-strand cord () comprises an internal layer (CI) made up of K=1 internal strand (TI) having two layers (C, C), with the internal layer (C) being made up of Q internal metallic threads (F) and the external layer (C) being made up of N external metallic threads (F), and an external layer (CE) made up of L>1 external strands (TE) having two layers (C', C′) wound around the internal layer (CI), with the internal layer (C′) being made up of Q′ internal metallic threads (F′) and the external layer (C′) being made up of N′ external metallic threads (F′). The cord () has an energy-to-break per unit area ES≥145 N·mmwith where is the sum of the forces at break, is the sum of the total elongation, Cfrag is the coefficient of weakening, and D is the diameter.

Two-layer multi-strand cable having an improved surface energy-to-break

A two-layer multi-strand cord () has a modulus EC such that 50 GPa&#x2264;EC&#x2264;160 GPa. The cord comprises: (a) an internal layer (CI) of the cord made up of J&#x3e;1 internal strands (TI) wound in a helix having a modulus EI, each internal strand (TI) comprising: an internal layer (C1) made up of Q&#x2265;1 internal threads (F1), and an external layer (C2) made up of N&#x3e;1 external threads (F2) wound around the internal layer (C1), and (b) an external layer (CE) of the cord made up of L&#x3e;1 external strands (TE) wound around the internal layer (CI) of the cord, each external strand (TE) comprising: an internal layer (C1') made up of Q&#x2032;&#x2265;1 internal threads (F1&#x2032;), and an external layer (C2&#x2032;) made up of N&#x2032;&#x3e;1 external threads (F2&#x2032;) wound around the internal layer (C1&#x2032;).

Two-layer multi-strand cables having very low, low and medium modulus

A two-layer multi-strand cord () comprises an internal layer (CI) of the cord made up of J&#x3e;1 internal strands (TI) and an external layer (CE) of the cord made up of L&#x3e;1 external strands (TE). The cord satisfies the relationship 95&#x2264;MC&#x2264;175, where MC=(J&#xd7;MI+L&#xd7;ME)/(J+L); MI=200&#xd7;cos(&#x3b1;)&#xd7;[Q&#xd7;(D1/2)&#xd7;cos(&#x3b2;)+N&#xd7;(D2/2)&#xd7;cos(&#x3b3;)]/[Q&#xd7;(D1/2)+N&#xd7;(D2/2)]; and ME=200&#xd7;cos(&#x3b1;')&#xd7;[Q&#x2032;&#xd7;(D1&#x2032;/2)&#xd7;cos(&#x3b2;&#x2032;)+P&#x2032;&#xd7;(D2&#x2032;/2)&#xd7;cos(&#x3b4;&#x2032;)+N&#x2032;&#xd7;(D3&#x2032;/2)&#xd7;cos(&#x3b2;&#x2032;)]/[Q&#x2032;&#xd7;(D1&#x2032;/2)+P&#x2032;&#xd7;(D2/2)+N&#x2032;&#xd7;(D3&#x2032;/2)], where D1, D1&#x2032;, D2, D2&#x2032;, and D3&#x2032; are in mm, &#x3b1; and &#x3b1;&#x2032; are the helix angle of each internal and external strand (TI), &#x3b2; and &#x3b2;&#x2032; are the helix angle of each internal thread (F1, F1&#x2032;), &#x3b4;&#x2032; is the helix angle of each intermediate thread (F2&#x2032;) and &#x3b3; and &#x3b3;&#x2032; are the helix angle of each external thread (F2, F3&#x2032;).

Two-layer multi-strand cords having very low, low and medium moduli

A two-layer multi-strand cord () comprises an internal layer (CI) of the cord made up of J&#x3e;1 internal strands (TI) and an external layer (CE) of the cord made up of L&#x3e;1 external strands (TE). The cord satisfies the relationship 100&#x2264;MC&#x2264;175, where MC=(J&#xd7;MI+L&#xd7;ME)/(J+L); MI=200&#xd7;cos(&#x3b1;)&#xd7;[Q&#xd7;(D/2)&#xd7;cos(&#x3b2;)+N&#xd7;(D/2)&#xd7;cos(&#x3b3;)]/[Q&#xd7;(D/2)+N&#xd7;(D/2)]; and ME=200&#xd7;cos(&#x3b1;')&#xd7;[Q&#x2032;&#xd7;(D&#x2032;/2)&#xd7;cos(&#x3b2;&#x2032;)+N&#x2032;&#xd7;(D&#x2032;/2)&#xd7;cos(&#x3b3;&#x2032;)]/[Q&#x2032;&#xd7;(D&#x2032;/2)+N&#x2032;&#xd7;(D&#x2032;/2)], where D, D&#x2032;, D, D&#x2032; are in mm, &#x3b1; and &#x3b1;&#x2032; are the helix angle of each internal and external strand (TI), &#x3b2; and &#x3b2;&#x2032; are the helix angle of each internal thread (F, F&#x2032;), and &#x3b3; and &#x3b3;&#x2032; are the helix angle of each external thread (F, F&#x2032;).

A two-layer multi-strand cord () comprises an internal layer (CI) of the cord made up of J&#x3e;1 internal strands (TI) and an external layer (CE) of the cord made up of L&#x3e;1 external strands (TE). The cord satisfies the relationship 95&#x2264;MC&#x2264;175, where MC=(J&#xd7;MI+L&#xd7;ME)/(J+L); MI=200&#xd7;cos(&#x3b1;)&#xd7;[Q&#xd7;(D/2)&#xd7;cos(&#x3b2;)+P&#xd7;(D/2)&#xd7;cos(&#x3b4;)+N&#xd7;(D/2)&#xd7;cos(&#x3b3;)]/[Q&#xd7;(D/2)+P&#xd7;(D/2)+N&#xd7;(D/2)]; and ME=200&#xd7;cos(&#x3b1;')&#xd7;[Q&#x2032;&#xd7;(D&#x2032;/2)&#xd7;cos(&#x3b2;&#x2032;)+N&#x2032;&#xd7;(D&#x2032;/2)&#xd7;cos(&#x3b3;&#x2032;)]/[Q&#x2032;&#xd7;(D&#x2032;/2)+N&#x2032;&#xd7;(D&#x2032;/2)], where D, D&#x2032;, D, D&#x2032;, and Dare in mm, &#x3b1; and &#x3b1;&#x2032; are the helix angle of each internal and external strand (TI), &#x3b2; and &#x3b2;&#x2032; are the helix angle of each internal thread (F, F&#x2032;), &#x3b4; is the helix angle of each intermediate thread (F) and &#x3b3; and &#x3b3;&#x2032; are the helix angle of each external thread (F, F&#x2032;).

A two-layer multi-strand cord () comprises an internal layer (CI) of the cord made up of J&#x3e;1 internal strands (TI) and an external layer (CE) of the cord made up of L&#x3e;1 external strands (TE). The cord satisfies the relationship 95&#x2264;MC&#x2264;180, where MC=(J&#xd7;MI+L&#xd7;ME)/(J+L); MI=200&#xd7;cos(&#x3b1;)&#xd7;[Q&#xd7;(D1/2)&#xd7;cos(&#x3b2;)+P&#xd7;(D2/2)&#xd7;cos(&#x3b4;)+N&#xd7;(D3/2)&#xd7;cos(&#x3b3;)]/[Q&#xd7;(D1/2)+P&#xd7;(D2/2)+N&#xd7;(D3/2)]; and ME=200&#xd7;cos(&#x3b1;')&#xd7;[Q&#x2032;&#xd7;(D1&#x2032;/2)&#xd7;cos(&#x3b2;&#x2032;)+P&#x2032;&#xd7;(D2&#x2032;/2)&#xd7;cos(&#x3b4;&#x2032;)+N&#x2032;&#xd7;(D3&#x2032;/2)&#xd7;cos(&#x3b3;&#x2032;)]/[Q&#x2032;&#xd7;(D1&#x2032;/2)+P&#x2032;&#xd7;(D2/2)+N&#x2032;&#xd7;(D3&#x2032;/2)], where D1, D1&#x2032;, D2, D2&#x2032;, D3 and D3&#x2032; are in mm, &#x3b1; and &#x3b1;&#x2032; are the helix angle of each internal and external strand (TI), &#x3b2; and &#x3b2;&#x2032; are the helix angle of each internal thread (F1, F1&#x2032;), &#x3b4; and &#x3b4;&#x2032; are the helix angle of each intermediate thread (F2, F2&#x2032;) and &#x3b3; and &#x3b3;&#x2032; are the helix angle of each external thread (F3, F3&#x2032;).

Growing community of inventors

Clermont-Ferrand, France

Stephane Laurent