Strand tension control

Claim 2

Apparatus for controlling the tension in advancing strand material comprising: coil means for generating an electromagnetic field of controllably variable flux density and having a first and second pole means for directing the flux of the field, each of said pole means having a plurality of spaced apart segments and the segments being parallel one to another and to a common axis, mounting means for mounting said pole means in predetermined relation one to the other with said segments in opposition and for mounting at least one of said pole means for flux density adjusting movement relative to the other thereof, said mounting means supporting said pole means for movement of said segments into and out of axial alignment and for movement thereof toward one another and apart, and rotor means for engaging a strand to be controlled and for imposing thereon a restraint determined by the flux density of the electro-magnetic field between said pole means, said rotor means having a strand engaging pulley means for engaging an advancing strand to be controlled and supported for rotation about said common axis and flux cutting means secured to said pulley means for rotation therewith and positioned for rotation between said pole means, said rotor means being restrained against being rotatably driven by advancement of the strand engaging said pulley means due to rotation of said flux cutting means through the electromagnetic field.

Claim 3

Apparatus according to claim 1 wherein each of said pole means is of generally circular configuration about a central axis and said pole means are mounted with said central axes aligned on a common axis, and further comprising bearing means for supporting said rotor means for rotation about said axis.

Claim 4

Apparatus according to claim 2 wherein said pulley means and said flux cutting means are spaced axially along said common axis one from the other and wherein said rotor means further has a shaft extending along said common axis and operatively connecting said pulley means and said flux cutting means.

Claim 5

Apparatus according to claim 2 wherein one of said pole means is fixedly disposed along said common axis between said pulley means and said flux cutting means and said mounting means supports the other of said pole means for said axial alignment movement and said movement of said segments toward one another and apart.

Claim 6

Apparatus according to claim 1 wherein each of said pole means is of generally circular configuration about a central axis, said pole means are mounted with said central axes aligned on a common axis, and said segments of said pole means extend parallel one to another and to said common axis.

Claim 7

Apparatus according to claim 5 wherein said segments of said pole means are uniformly spaced about the circumferences of said pole means and further wherein said mounting means supports one of said pole means for rotation about said central axis thereof and thereby for said axial alignment movement of said segments.

Claim 8

Apparatus according to claim 6 wherein said mounting means fixedly supports the other of said pole means and supports said one pole means for movement along said common axis and thereby for said movement of said segments toward one another and apart.

Claim 9

Apparatus according to claim 1 further comprising electrical control means electrically connected with said coil means for controllably electrically energizing said coil means and thereby for generating an electromagnetIc field having a flux density dependent in part upon the electrical energization of said coil means by said control means.

Claim 10

Apparatus according to claim 8 wherein said control means comprises set point means for establishing a predetermined desired level of electrical energization and for maintaining such level as an open loop control over the restraint imposed on an engaged advancing strand.

Claim 11

Apparatus according to claim 8 wherein said control means comprises sensor means for detecting the tension level of the strand engaging said pulley means and further wherein said control means responds to sensed variations in tension level by varying the level of electrical energization as a closed loop control over the restraint imposed on an engaged advancing strand.

Claim 12

In a textile yarn processing apparatus having means for advancing thermoplastic strand materials along a predetermined path of travel, heater means disposed at a predetermined location along the path of travel for heating an advancing strand and thereby for setting the strand in a desired condition, and twisting means disposed adjacent the heater means for inserting twist into the heated strand, the improvement therewith of means for protecting against undesirable excessive variation in the desired condition of the strand and comprising: rotor means having pulley means supported adjacent the heater means for engaging the strand in advance of the heater means and the twisting means and for rotation about a common axis in response to advancement of the engaged strand and having flux cutting means secured to said pulley means for rotation therewith about said axis, coil means for generating an electromagnetic field of controllably variable flux density and having first and second pole means for directing the flux of the field, each of said pole means having a plurality of spaced apart segments and the segments being parallel one to another and to said axis, and mounting means for mounting said pole means on opposite sides of said flux cutting means and in predetermined relation on to the other with said segments in opposition and for mounting at least one of said pole means for flux density adjusting movement relative to the other thereof, said mounting means supporting said pole means for movement of said segments into and out of axial alignment and for movement thereof toward one another and apart, the controlled flux density of the electromagnetic field imposing a controlled restraint on rotation of the rotor means and thereby maintaining tension conditions in the strand more uniform during twisting and heating of the strand so as to facilitate consistent attainment of the desired condition.

Claim 13

In a textile yarn processing apparatus having means for advancing thermoplastic strand materials along a predetermined path of travel, heater means disposed at a predetermined location along the path of travel for heating an advancing strand and thereby for setting the strand in a desired condition, and twisting means disposed adjacent the heater means for inserting twist into the heated strand, the improvement therewith of means for protecting against undesirable excessive variation in the desired condition of the strand and comprising: rotor means having pulley means supported adjacent the heater means for engaging the strand in advance of the heater means and the twisting means and for rotation about a common axis in response to advancement of the engaged strand and having flux cutting means secured to said pulley means for rotation therewith about said axis, coil means for generating an electromagnetic field of controllably variable flux density and having first and second pole means for directing the flux of the field, each of said pole means having a plurality of spaced apart segments and the segments being parallel one to another and to said axis, and mounting means for mounting said pole means on opposite sides of said flux cutting means and in predetermined relation on to the other with said segments in opposition and for mounting at least one of said pole means for flux density adjusting movement relative to the other thereof, said mounting means supporting said pole means for movement of said segments into and out of axial alignment and for movement thereof toward one another and apart, the controlled flux density of the electromagnetic field imposing a controlled restraint on rotation of the rotor means and thereby maintaining tension conditions in the strand more uniform during twisting and heating of the strand so as to facilitate consistent attainment of the desired condition.

Claim 14

Apparatus according to claim 11 further comprising electrical control means electrically connected with said coil means for controllably electrically energizing said coil means and thereby for generating an electromagnetic field having a flux density dependent in part upon the electrical energization of said coil means by said control means.

Claim 15

Apparatus according to claim 12 wherein said control means comprises set point means for establishing a predetermined desired level of electrical energization and for maintaining such level as an open loop control over the restraint imposed on an engaged advancing strand.

Claim 16

Apparatus according to claim 12 wherein said control means comprises sensor means for detecting the tension level of the strand engaging said pulley means and further wherein said control means responds to sensed variations in tension level by varying the level of electrical energization as a closed loop control over the restraint imposed on an engaged advancing strand.

Claim 17

In an apparatus having creel means for receiving and supporting a plurality of packages of strand material and for delivering a plurality of strands along predetermined paths of travel, and winding means disposed at a predetermined location along the paths of travel for drawing strands from the creel means and for winding the strands about a beam, the improvement therewith of means for protecting against undesirable excessive variation in the tension desired condition of the strands and including a number of tension control apparatus corresponding to the number of the strands, each tension control apparatus comprising: rotor means having pulley means supported adjacent the creel means for engaging a corresponding one strand as the strand is drawn from the creel means and for rotation about a common axis in response to advancement of the engaged strand and having flux cutting means secured to said pulley means for rotation therewith about said axis, coil means for generating an electromagnetic field of controllably variable flux density and having first and second pole means for directing the flux of the field, each of said pole means having a plurality of spaced apart segments and the segments being parallel one to another and to said axis, and mounting means for mounting said pole means on opposite sides of said flux cutting means and in predetermined relation one to the other with said segments in opposition and for mounting at least one of said pole means for flux density adjusting movement relative to the other thereof, said mounting means supporting said pole means for movement of said segments into and out of axial alignment and for movement thereof toward one another and apart, the controlled flux density of the electromagnetic field imposing a controlled restraint on rotation of the rotor means and thereby maintaining tension conditions in the strand more uniform during winding of the strand.

Claim 18

In an apparatus having creel means for receiving and supporting a plurality of packages of strand material and for delivering a plurality of strands along predetermined paths of travel, and winding means disposed at a predetermined location along the paths of travel for drawing strands from the creel means and for winding the strands about a beam, the improvement therewith of means for protecting against undesirable excessive variation in the tension desired condition of the strands and including a number of tension control apparatus corresponding to the number of the strands, each tension control apparatus comprising: rotor means having pulley means supported adjacent the creel means for engaging a corresponding one strand as the strand is drawn from the creel means and for rotation about a common axis in response to advancement of the engaged strand and having flux cutting means secured to said pulley means for rotation therewith about said axis, coil means for generating an electromagnetic field of controllably variable flux density and having first and second pole means for directing the flux of the field, each of said pole means having a plurality of spaced apart segments and the segments being parallel one to another and to said axis, and mounting means for mounting said pole means on opposite sides of said flux cutting means and in predetermined relation one to the other with said segments in opposition and for mounting at least one of said pole means for flux density adjusting movement relative to the other thereof, said mounting means supporting said pole means for movement of said segments into and out of axial alignment and for movement thereof toward one another and apart, the controlled flux density of the electromagnetic field imposing a controlled restraint on rotation of the rotor means and thereby maintaining tension conditions in the strand more uniform during winding of the strand.

Claim 19

Apparatus according to claim 15 further comprising electrical control means electrically connected with each of said coil means for controllably electrically energizing said coil means and thereby for generating an electromagnetic field having a flux density dependent in part upon the electrical energization of said coil means by said control means.

Claim 20

Apparatus according to claim 16 wherein said control means comprises set point means electrically connected with a plurality of said coil means for establishing a common predetermined desired level of electrical energization and for maintaining such level as an open loop control over the restraint imposed on the corresponding engaged advancing strands.

Claim 21

Apparatus according to claim 16 wherein said control means comprises sensor means for detecting the tension in a plurality of strands and further wherein said control means responds to sensed variations in average tension level in the plurality of strands by varying the level of electrical energization of a group of said coil means as an averaging control over the restraint imposed on the advancing strands.

Claim 22

Apparatus according to claim 16 wherein said control means comprises a number of sensor means corresponding to the number of strands, each sensor means detecting the tension level of the corresponding one strand engaging the corresponding one pulley means and further wherein said control means responds to sensed variations in tension level in individual strands by varying the level of electrical energization of the corresponding one coil means as a closed loop control over the restraint imposed on the corresponding engaged advancing strand.