Method and device of dynamically configuring linear density and blending ratio of yarn by three-ingredient asynchronous/synchronous drafted

A method of dynamically configuring a linear density and a blending ratio of a yarn by three-ingredient asynchronous/synchronous drafting, comprising:

• providing an actuating mechanism, wherein the actuating mechanism includes a three-ingredient asynchronous/synchronous two-stage drafting mechanism, a twisting mechanism and a winding mechanism;
• wherein the three-ingredient asynchronous/synchronous two-stage drafting mechanism includes a first stage asynchronous drafting unit and a successive second stage synchronous drafting unit;
• providing a combination of a plurality of back roller and a middle roller included by the first stage asynchronous drafting unit;
• wherein the combination of back rollers has three rotational degrees of freedom and includes a first back roller, a second back roller, a third back roller, which are set abreast on a same back roller shaft;
• the first back roller, the second back roller, the third back roller move at the speeds Vh1, Vh2, and Vh3 respectively;
• the middle roller rotates at the speed Vz;
• the second stage synchronous drafting unit includes a front roller and the middle roller;
• the front roller rotates at the surface linear speed Vq;
• assuming the linear densities of a first roving yarn ingredient, a second roving yarn ingredient, a third roving yarn ingredient drafted by the first back roller, the second back roller, the third back roller are respectively ρ1, ρ2, and ρ3, the linear density of the yarn Y drafted and twisted by the front roller is ρy;
• ρ
• y
• =
• 1
• V
• q
• ⁢
• (
• V
• h
• ⁢
• ⁢
• 1
• *
• ρ
• 1
• +
• V
• h
• ⁢
• ⁢
• 2
• *
• ρ
• 2
• +
• V
• h
• ⁢
• ⁢
• 3
• *
• ρ
• 3
• )
• (
• 1
• )
• the blending ratios of the first roving yarn ingredient, the second roving yarn ingredient, and the third roving yarn ingredient are respectively k1, k2, and k3;
• k
• 1
• =
• ρ
• 1
• ″
• ρ
• 1
• ″
• +
• ρ
• 2
• ″
• +
• ρ
• 3
• ″
• =
• ρ
• 1
• ′
• ρ
• 1
• ′
• +
• ρ
• 2
• ′
• +
• ρ
• 3
• ′
• =
• ρ
• 1
• *
• V
• h
• ⁢
• ⁢
• 1
• ρ
• 1
• *
• V
• h
• ⁢
• ⁢
• 1
• +
• ρ
• 2
• *
• V
• h
• ⁢
• ⁢
• 2
• +
• ρ
• 3
• *
• V
• h
• ⁢
• ⁢
• 3
• k
• 2
• =
• ρ
• 2
• ″
• ρ
• 1
• ″
• +
• ρ
• 2
• ″
• +
• ρ
• 3
• ″
• =
• ρ
• 2
• ′
• ρ
• 1
• ′
• +
• ρ
• 2
• ′
• +
• ρ
• 3
• ′
• =
• ρ
• 2
• *
• V
• h
• ⁢
• ⁢
• 2
• ρ
• 1
• *
• V
• h
• ⁢
• ⁢
• 1
• +
• ρ
• 2
• *
• V
• h
• ⁢
• ⁢
• 2
• +
• ρ
• 3
• *
• V
• h
• ⁢
• ⁢
• 3
• k
• 3
• =
• ρ
• 3
• ″
• ρ
• 1
• ″
• +
• ρ
• 2
• ″
• +
• ρ
• 3
• ″
• =
• ρ
• 3
• ′
• ρ
• 1
• ′
• +
• ρ
• 2
• ′
• +
• ρ
• 3
• ′
• =
• ρ
• 3
• *
• V
• h
• ⁢
• ⁢
• 3
• ρ
• 1
• *
• V
• h
• ⁢
• ⁢
• 1
• +
• ρ
• 2
• *
• V
• h
• ⁢
• ⁢
• 2
• +
• ρ
• 3
• *
• V
• h
• ⁢
• ⁢
• 3
• keeping the ratio of linear speeds of the front roller and the middle roller Vq/Vz constant, the speeds of the front roller and the middle roller depend on reference linear density of the yarn;
• adjusting the rotation rates of the first back roller, the second back roller, the third back roller, so as to dynamically adjust the linear density and a blending ratio K of a yarn Y online.