Method and apparatus for precision pattern knitting on a warp knitting machine

A method of controlling tension of lay-in warp yarns knitted on a warp knitting machine, said method comprising the steps of:

• (A) providing one or more flutter bars working with a warp knitting machine, each of said one or more flutter bars contacting a corresponding portion of lay-in warp yarn to be knitted and which passes across each flutter bar, each flutter bar being capable of increasing and decreasing tension on the lay-in warp yarn passing thereacross;
• (B) providing computer control and movement means for controlled movement of at least one of said one or more flutter bars;
• and
• (C) utilizing said computer control and movement means during knitting to move said one or more flutter bars such that said one or more flutter bars increases and decreases tension of lay-in warp yarn passing thereacross.

In a warp knitting machine for knitting a plurality of yarns into a fabric, the improvement comprising an apparatus for controlling tension of lay-in warp yarns, said apparatus comprising:

• (A) at least a pair of rotatable flutter bars working with a warp knitting machine for each contacting a respective divided-out portion of lay-in warp yarn to be knitted and which passes across each flutter bar, each flutter bar being moveable such that each flutter bar during knitting can increase and decrease tension on the lay-in warp yarn which passes thereacross and said flutter bars being connected such that rotational movement of one causes rotational movement of the other;
• (B) movement means connected to at least one of said flutter bars for moving at least one of said flutter bars during knitting;
• and
• (C) computer means connected to and controlling said movement means;
• (D) whereby said computer means can cause said movement means to move at least one of said flutter bars during knitting which moves the other of said flutter bars such that said flutter bars can during knitting increase and decrease tension on the lay-in warp yarn which passes thereacross.

In a warp knitting machine comprising lay-in warp yarns for knitting into a fabric, the improvement comprising an apparatus for controlling tension of the lay-in warp yarns, said apparatus comprising:

• (A) at least a first flutter bar and a second flutter bar, each of the flutter bars contacting a respective divided-out portion of lay-in warp yarn to be knitted and which passes across each flutter bar, and each flutter bar being rotatably movable such that each flutter bar can alternatingly increase and decrease tension of lay-in warp yarn passing thereacross;
• (B) said flutter bars being connected at one end thereof such that movement of said first flutter bar to increase or decrease tension of the lay-in warp yarn passing thereacross causes simultaneous movement of said second flutter bar to oppositely increase or decrease tension of the lay-in warp yarn passing thereacross;
• (C) a reducer operatively connected to said first flutter bar for moving said first flutter bar;
• (D) a servomotor driveably connected to said reducer;
• and
• (E) computer means connected to said servomotor for controlling said servomotor;
• (F) whereby said computer means can actuate said servomotor to drive said reducer to move said first flutter bar to in turn simultaneously move said second flutter bar such that said flutter bars can alternatingly increase and decrease tension of the lay-in warp yarns passing thereacross.

In a warp knitting machine for knitting lay-in warp yarn into a fabric, the improvement comprising an apparatus for controlling tension of at least a portion of the lay-in warp yarn, said apparatus comprising:

• (A) at least one rotatably moveable flutter bar comprising a shaft having a parallel and spaced-apart contact arm for tensioning lay-in warp yarn prior to knitting, said flutter bar being rotatable on a longitudinal axis of said shaft whereby said contact arm also rotates such that said contact arm can during knitting increase and decrease tension on lay-in warp yarn passing thereacross;
• (B) movement means operatively connected to said flutter bar for rotating said flutter bar during knitting;
• and
• (C) computer means operatively connected to and controlling said movement means;
• (D) whereby said computer means can cause said movement means to rotate said flutter bar during knitting.

In a warp knitting machine for knitting a plurality of yarns into a fabric, the improvement comprising an apparatus for controlling tension of lay-in warp yarns, said apparatus comprising:

• (A) at least a pair of rotatable flutter bars working with a warp knitting machine for each contacting a respective divided-out portion of lay-in warp yarn to be knitted and which passes across each flutter bar, each flutter bar being moveable such that each flutter bar can increase and decrease tension on the lay-in warp yarn which passes thereacross and said flutter bars being connected such that rotational movement of one causes rotational movement of the other;
• (B) movement means connected to at least one of said flutter bars for moving at least one of said flutter bars;
• (C) computer means connected to and controlling said movement means;
• (D) whereby said computer means can cause said movement means to move at least one of said flutter bars which moves the other of said flutter bars such that said flutter bars can increase and decrease tension on the lay-in warp yarn which passes thereacross;
• and
• (E) wherein said movement means is connected to an end of a first of said flutter bars and said flutter bars are connected to each other at an opposite end such that movement of said first flutter bar causes simultaneous movement of the other of said flutter bars.

In a warp knitting machine for knitting a plurality of yarns into a fabric, the improvement comprising an apparatus for controlling tension of lay-in warp yarns, said apparatus comprising:

• (A) at least a pair of rotatable flutter bars working with a warp knitting machine for each contacting a respective divided-out portion of lay-in warp yarn to be knitted and which passes across each flutter bar, each flutter bar being moveable such that each flutter bar can increase and decrease tension on the lay-in warp yarn which passes thereacross and said flutter bars being connected such that rotational movement of one causes rotational movement of the other;
• (B) movement means connected to at least one of said flutter bars for moving at least one of said flutter bars;
• (C) computer means connected to and controlling said movement means;
• (D) whereby said computer means can cause said movement means to move at least one of said flutter bars which moves the other of said flutter bars such that said flutter bars can increase and decrease tension on the lay-in warp yarn which passes thereacross;
• and
• (E) wherein said movement means comprises a reducer for moving at least one of said flutter bars and a servomotor driveably connected to said reducer.

In a warp knitting machine for knitting a plurality of yarns into a fabric, the improvement comprising an apparatus for controlling tension of lay-in warp yarns, said apparatus comprising:

• (A) at least a pair of rotatable flutter bars working with a warp knitting machine for each contacting a respective divided-out portion of lay-in warp yarn to be knitted and which passes across each flutter bar, each flutter bar being moveable such that each flutter bar can increase and decrease tension on the lay-in warp yarn which passes thereacross and said flutter bars being connected such that rotational movement of one causes rotational movement of the other;
• (B) movement means connected to at least one of said flutter bars for moving at least one of said flutter bars;
• (C) computer means connected to and controlling said movement means;
• (D) whereby said computer means can cause said movement means to move at least one of said flutter bars which moves the other of said flutter bars such that said flutter bars can increase and decrease tension on the lay-in warp yarn which passes thereacross;
• and
• (E) wherein said movement means comprises a reducer for moving at least one of said flutter bars and a servomotor driveably connected to said reducer and wherein said computer means is connected to and controls said servomotor.