Twisting method and installation with tension control for the production of reinforcing cords for tires

Patent metadata

Field	Value
Publication number	US-11332853-B2
Application number	US-201816954101-A
Country	US
Kind code	B2
Filing date	Dec 18, 2018
Priority date	Dec 22, 2017
Publication date	May 17, 2022
Grant date	May 17, 2022

Abstract

The method for producing a wire element by interlacing at least a first strand and a second strand, during which strand tension control is effected by includes defining an assembly tension set point representative of a state of longitudinal tension to be obtained in the first strand when said first strand reaches the assembly point. The method also includes measuring the actual assembly tension applied in the first strand, said measurement being taken at a first tension measurement point located along the first strand and upstream of the assembly point. The method proceeds with operating a tension regulating member such as a capstan, which acts on the first strand upstream of the assembly point such as to cause the actual assembly tension within said first strand to converge automatically towards the assembly tension set point.

First claim

The invention claimed is:

1. A method for manufacturing a wire element by interlacing at least one first strand and one second strand distinct from the first strand, said method comprising the following steps:
an infeed step (a), during which the first strand and the second strand, respectively, are routed to an assembly point, at which the first strand and the second strand meet;
an interlacing step (b), during which the first strand and the second strand are interlaced with each other, at the assembly point, so as to form a wire element from said at least first and second strands,
selecting either a tension mode a tension control mode or a speed control mode;
in response to the selection of the tension control mode, said method comprising a strand tension control step (a1), in a closed loop, during which step:
a tension setpoint, called “assembly tension setpoint”, is defined that represents a longitudinal tension state intended to be obtained in the first strand when said first strand reaches the assembly point;
the tension, called “actual assembly tension” (T_actual), that is exerted inside said first strand is measured at a first tension measurement point that is located along said first strand and upstream of the assembly point relative to the routing direction of said first strand;
a tension feedback loop is used to determine an error, called “tension error” (ER_T), that corresponds to the difference between the assembly tension setpoint and the actual assembly tension of the first strand; and
a tension regulating component is controlled, on the basis of said tension error, which component acts on the first strand upstream of the assembly point, so as to automatically converge, inside said first strand, the actual assembly tension (T_actual) towards the assembly tension setpoint (T_set); and
in response to the selection of the speed control mode, said method comprising a speed control step, in a closed loop, during which step:
a speed setpoint setting component that allows a setpoint, called “forward speed setpoint”, is defined that represents a forward speed value intended to be imparted to the first strand upstream of the assembly point,
a forward speed value, called “actual forward speed” of the first strand is measured at a speed measurement point upstream of the assembly point,
an error, called “speed error”, is calculated to be the difference between the forward speed setpoint and the actual forward speed of the first strand, and
a speed regulating component, which is dependent on the speed feedback component and which can act on the first strand upstream of the assembly point, automatically converges the actual forward speed of the first strand towards the forward speed setpoint.

2. The method according to claim 1 , wherein, during the infeed step (a), the first strand is moved towards the assembly point by means of a motorized drive device that is located upstream of said assembly point and is configured to act as the speed regulating component to impart a speed, called “forward speed”, to the first strand in response to the selection of the speed control mode and is configured to act as the tension regulating component to impart a tension in the first strand in response to the selection of the tension control mode.

3. The method according to claim 2 , wherein, during the strand tension control step (a1), the motorized drive device is used as a tension regulating component by adjusting, as a function of the tension error, the drive setpoint that is applied to said motorized drive device.

4. The method according to claim 1 , wherein, during the infeed step (a), the first strand is moved towards the assembly point by means of a motorized drive device that is located upstream of the assembly point, and wherein said method comprises an unwinding step (a0), during which the first strand is unwound from an input reel, by means of an unwinding device, which is distinct from the motorized drive device and which is located upstream of said motorized drive device and which comprises a motorized reel holder intended to receive and to rotate the input reel, at a selected speed called “input reel speed”, and wherein the tension, called actual “unwinding tension”, that is exerted in the first strand is measured at a second tension measurement point that is located along the first strand, between the motorized reel holder and the motorized drive device, and the input reel speed is adjusted so as to converge said actual unwinding tension towards a predetermined unwinding tension setpoint.

5. The method according to claim 1 , wherein each of the first and second strands is controlled separately, the first strand in accordance with the strand tension control step (a1), and the second strand in accordance with a speed control step (a2), by which a forward speed setpoint is set that corresponds to a forward speed value intended to be imparted to the second strand upstream of the assembly point, and a speed regulating component is used that acts on the second strand upstream of the assembly point, so as to automatically converge the actual forward speed of the second strand towards the setpoint forward speed.

6. The method according to claim 1 , wherein it comprises a selection step, by which a decision is taken to opt either for tension control of the second strand by applying, mutatis mutandis, a tension control step (a1) to the second strand, or for speed control of the second strand in accordance with a speed control step (a2), by which a forward speed setpoint is set, which corresponds to a forward speed value intended to be imparted to the second strand upstream of the assembly point, and a speed regulating component is used that acts on the second strand upstream of the assembly point, so as to automatically converge the actual forward speed of the second strand towards the forward speed setpoint.

7. The method according to claim 1 , wherein the actual assembly tension of the considered strand is measured by means of a tension monitoring component comprising a thread guide which comes into abutment against the first strand and which is supported by a resiliently deformable support, the resilient deformation of which is measured by means of a suitable sensor.

8. The method according to claim 1 , wherein, during the interlacing step (b), the interlacing is carried out by twisting so as to helically wind the second strand around the first strand or to helically wind the second strand and the first strand around each other, so as to form the wire element.

9. An installation for manufacturing a wire element by interlacing at least one first strand and one second strand distinct from the first strand, said installation comprising:
an infeed device responsible for routing the first strand and the second strand, respectively, to an assembly point, at which the first strand and the second strand meet;
an interlacing device responsible for interlacing the first strand and the second strand with each other, at the assembly point, so as to form a wire element from said at least first and second strands,
wherein said installation comprises a selector that allows the installation to operate in a “tension control mode” or a “speed control mode;”
a tension control unit, arranged to control the strand tension in a closed loop according to the tension control mode, said tension control unit to this end comprising:
a tension setpoint setting component that allows a tension setpoint, called “assembly tension setpoint”, to be set that represents a longitudinal tension state intended to be obtained in the first strand when said first strand reaches the assembly point;
a tension monitoring component that allows the tension, called “actual assembly tension

Assignees

• Michelin & Cie

Inventors

• Cornille Richard
• Hombert Christophe
• Aubarede Francis

Classifications

• D07B2301/3591

  Linear speed · CPC title

• D07B2301/3583

  Rotational speed · CPC title

• D07B2301/258

  Tensile stress · CPC title

• D07B7/02

  Machine details; Auxiliary devices · CPC title

• D07B3/08

  in which the take-up reel rotates about the axis of the rope or cable {or in which a guide member rotates about the axis of the rope or cable to guide the rope or cable on the take-up reel in fixed position} and the supply reels are fixed in position · CPC title