US2990675A - Breakage detector for yarn - Google Patents

Description

July 4, 1961 v. c. REES BREAKAGE DETECTOR FOR YARN 2 Sheets-Sheet 1 Filed Oct. 10, 1957 INVENTOR. 021 C? 121% ggefi dw e ATTORNEYS July 4, 1961 v.,,c. REES BREAKAGE DETECTOR FOR YARN Filed Oct. 10, 1957 2 Sheets-Sheet 2 INVEN TOR. Zmm a Q BY I l l l United States Patent 2,990,675 BREAKAGE DETECTOR FOR YARN Vernon C. Rees, Monroe County, Mich., assiguor, by mesne assignments, to Johns-Manville Fiber Glass Inc., Cleveland, Ohio, a corporation of Delaware Filed Oct. 10, 1957, Ser. No. 689,315 SClaims. (01.57-81) This invention relates broadly to improvements in means and methods of controlling the feeding of yarns to twisting apparatus. More specifically, it relates to the detection of breaks in the yarn between the feeder and the twister.

The breakage detector forming the subject matter of this invention is particularly adapted for use with yarn com-prised of collected glass filaments, but this is in no wise to be construed as to being a limiting factor.

Many devices, including switches interposed in the circuit to the feeder motor, have been devised to detect breakage of the strand, however, all such known devices have been proven to be inadequate under normal plant operating and maintenance conditions. Factors contributing chiefly to that inadequacy include fouling of the mechanism by lint and dust and breakage of the detector by personnel when cleaning the twisting apparatus.

Since the twisting apparatus is normally comprised of multiple units arranged in one or more banks with a common drive means for all the bobbins or spools upon which the twisted yarn is wound in any one bank, the chance of any one breakage detector becoming inoperative is in direct relation to the number of twisters involved. It is obvious that such repairs are not only costly from a maintenance standpoint but also adversely affect production.

Another factor influencing the design of a breakage detector for yarn is that it is advantageous that any feeler member associated with the detector lightly contact the longitudinally moving yarn to reduce stretch and breakage thereof. However, the feeler means, upon breakage of the yarn, should without fail move to another position. The means for applying the force to move the feeler to the second position without failure is generally antipodal to the light contact, as may best be exemplified by a spring. A spring which will maintain the feeler in light contact with the continuous strand of yarn, does not exert sufiicient force upon the feeler to assure full and prompt movement of the feeler to the second position upon breakage of the strand.

It is therefore an object of this invention to provide a broken strand detector which maintains a feeler in light contact with the continuous strand.

It is another object of this invention to provide a broken strand detector including a feeler which positively moves to a second position upon breakage of the strand.

. It is another object of this invention to provide a broken strand detector including a movable feeler which is protected from lint and dust.

It is still another object of this invention to provide a broken strand detector of rugged construtcion.

Other objects and advantages of the invention will become more apparent during the course of the following description when taken in connection with the accompanyin g drawings.

In the drawings wherein like numerals are employed to designate like parts throughout the same:

FIG. 1 is an isometric elevation view of the strand breakage detector showing its relation to twisting apparatus;

FIG. 2. is an isometric drawing of the strand breakage detector;

Patented July 4, 1961 FIG. 3 is a drawing in elevation of the strand breakage detector with parts broken away, to show the interior construction thereof;

FIG. 4 is a sectional drawing of the strand breakage detector taken on the line 4-4 of FIG. 3; and

FIG. 5 is a schematic diagram illustrating the cooperating electro-mechanical elements of the twisting apparatus including the strand breakage detector.

Referring to FIGS. 1 and 5 of the drawings, the numral 10 designates a yarn twisting frame in general.

The yarn feeding apparatus 11 is generally mounted on the uppermost shelf 12 of the frame and is adapted to control the rate at which the yarn is fed to the twisting apparatus. An electric motor 13 drives the yarn feeder or combination of the yarn supply reel 14 and the bobbin 15 at a constant speed.

The strand breakage detector, generally indicated by the numeral 16, is mounted on a shelf 17 below the feeding apparatus 1 1 and is in substantially vertical alignment therewith. The strand breakage detector 16 will be described in detail hereinafter.

An electrical control box 18 is mounted on the shelf 17 adjacent the break detector '16 and houses a switch 19 (FIG. 5) which is manually closed by depressing a handle 20 outside the box and which handle is provided with an operating rod 21 terminating in a projection 22 which is adapted to latch the switch 19 in closed position by engaging the normally extended plunger 23 of a solenoid 24, as is shown in FIG. 5. The rod 21 is normally urged to the normally open position of switch 19 by a spring 25. One end of a cable 26 is joined to the terminal end of the rod 21, is threaded over one or more direction changing pulleys 27 and the other end is attached to a slide 28 which is mounted for limited movement upon a lower shelf 29 of the frame in a direction extending transversely of the shelf.

The slide 28 carries a rotatably mounted spindle 30 provided with a pulley 31 positioned a short distance above the top surface of the slide. A spool or bobbin 32 is engaged by the portion of the spindle 30 above the pulley 31 in any convenient manner so that the spool will rotate with the spindle. A spring 33 is enclosed in each of a pair of housings 34 in such a manner as to urge the slide 28 to its forward position upon release of the projection 22 from the solenoid plunger 23-.

The structure described in detail above functions to move the slide 28 so that the surface of the pulley 31 is moved into engaging position with a flat belt 35, which is advanced by an electric motor 36, to rotate the spindle 30 and the spool 32 in unison upon closing of the switch 19. When the solenoid 24 is energized, in a manner to be hereinafter described, its plunger 23 will be retracted from latching engagement with the projection 22, spring 25 will open the contacts of switch 19 and springs 33 will move the slide forward to disengage the pulley 31 of spindle 30 from the belt 35.-

A twister ring 37 is mounted in a conventional manner on a framework 38, forming a part of the twisting frame, to encircle the spool 32 and to traverse the yarn over the spool in a vertical direction.

Referring particularly to FIGS. 2, 3 and 4, the strand breakage detector 16 includes a rectangular five-sided shell 39 formed of sheet metal with the open bottom closed by the shelf 17 upon which it is mounted with the front face 40 of the shell flush with the front edge of the shelf 17. The rear face 41 of the shell is parallel to the front face 40 and spaced therefrom by the top 42 and two parallelly disposed sides 43 so that, in conjunction with the shelf 17, they combine to form a chamber 44.

A guide rod 45 is welded to the top 42 of the shell 3 39 slightly to the left of the vertical centerline passing through the front face 40, as viewed in FIGS. 2 and 4, and extends into'space in front of the face 40. A circular hole 46 is cut in the front face 40 of the shell 39 on the vertical centerline at a point slightly above the horizontal centerline thereof.

A circular tube 47 projects forwardly from the front face 40 of the shell 39 with its wall 48 disposed concentrically with respect to the hole 46. A pair of spaced apart holes 49 and 50, which are substantially square in configuration, are cut into the wall of the tube 47, in the lower left-hand quadrant as viewed from the front, at a point extending from approximately 30 below the horizontal centerline to 60 therebelow, as particularly shown in FIG. 4. A plug 51 closes the end of the tube 47' and is held in place in any suitable manner, such as by welding or brazing. A conical bearing 52 enters the enclosed end of the plug 51 on the longitudinal axis of the tube 47 and is adapted to receive a pivot 53 formed on one end of a rod, generally indicated by the numeral 54. The rod 54. extends longitudinally on the axis of the tube through the hole 46 in the front face 40 of the shell '39, through the chamber 44 and terminates in a pivot 55 received by a bearing 56 entering through the rear face 41 ofthe shell. The bearing 56 is a hex head screw modified at the threaded end by a conical depression similar to 52 which is machined into the end on the longitudinal axis thereof. A circular hole 57 is cut in the rear face 41 of the shell 39 in alignment with the longitudinal axis of the tube 47 and the rod 54, and an internally threaded boss 58 is welded to the outside of the rear face 41 with the threads in alignment with hole 57. The bearing 56 is threadedly engaged by the boss 58 and a locknut 59 permits adjustment of the bearing to limit end play of the rod 54.

A U shaped feeler 60 of light gauge wire has an elongated base 61 and shortened parallel legs 62 and 63. The legs 62 and 63 respectively extend through the holes 49 and 50 in the tube 47 and are butt welded to the rod 54.

A thin bar of magnetic metal, which is hereby designated as a switch actuator 64 is welded at its longitudinal mid-point to the underside of the rod 54 adjacent the front face 40 but within the chamber 44 in a position radially rotated 30 clockwise from the position of the feeler 60, as viewed from the front, and as is best shown in 'FIG. 4. Also, as viewed from this position, the right hand leg 65 of the switch actuator 64 operates in the upper right hand quadrant and the left hand leg 66 operates in the lower left hand quadrant.

A weight 67 is frietionally retained in any position within an elongated slot 68 formed through the leg 65 of the switch actuator 64 extending in a direction away from the pivot rod 54. The rod 54, the feeler 60 and the switch actuator 64 combine to form a feeler assembly 69. The proper position of the weight 67 within the slot 68 is that position where the weight of the feeler assembly 69 to the right of the pivot rod 54 is slightly greater than the weight to the left of the pivot rod 54, when facing the front as in FIG. 4. This distribution of weight provides a force that is suflicient to rotate the feeler assembly 69 in a clockwise direction upon breakage of the strand, but the force is not sufficient to break or materially stretch the strand.

A switch 70 requiring a small amount of energy and travel to operate it, such as a micro switch, is secured to the front face 40 within the chamber 44 by screws 71 with its operating plunger 72 slightly below the horizontal centerline-of the rod 54 and in position to be depressed by the right leg 65 of the actuator 64 when it rotates to the horizontal or dashed line position of FIG. 4.

A permanent magnet 73 is mounted in a depending manner from an inverted L-shaped bracket 74 by one or more screws 75 with its face 76 in approximate horizontal alignment with the top of the plunger 72 when in extended position. The bracket 74 is fastened by screws 77 to the side wall 43 opposite the switch 70 to position the magnet 73 in the path of the left hand leg 66 of the switch actuator 64 and the magnet attracts the switch actuator 64 as it moves toward the dashed line horizontal position of FIG. 4. At this point it is appropriate to designate that it is preferred that all other metal parts of the break detector 16 in close proximity to the magnet 73, other than the switch actuator 64, are preferably made of non-magnetic materials.

Preliminary to initiating the twisting operation, the strand of yarn 78 is threaded from the reel 14 into the space between the guide rod 45 and the tube 47, over the feeler 60 to depress the feeler into the solid line position shown in FIG. 4, through the twister ring 37 and started on the spool 32. The threading is illustrated in FIGS. 1, 2 and 4. It will be noted that when the feeler 60 is depressed by the strand of yarn 78 that the switch actuator 64 is moved out of contact with the plunger 72 of switch 70 and with the magnet 73.

Referring to FIG. 5 the circuit for energizing the yarn feed motor 13 extends from a main 79 through a master switch 80, to one contact 81 of the switch 19, which when closed manually in the manner previously disclosed, bridges the gap to the other contact 82, and the circuit continues to the motor 13 and to the other main 83 passing through the other side of the master switch 80.

A control circuit is held ineffective so long as the strand of yarn 78 remains continuous, but becomes effective upon breakage of the strand of yarn, whereupon the circuit extends from the main 79 through line 84,. contacts 85 and 86 of switch 70, line 87, solenoid 24 and line 88 to the other side of the main 83.

A third circuit extends parallel to the yarn feed motor circuit and supplies current to the spindle drive motor 36. This circuit extends from main 79 through line 89, motor 36 and line 90 to the other main 83.

After threading the strand of yarn 78, as previously described, the master switch is closed which will energize the spindle drive motor 36, but since the pulley 31 on the spindle 30 is not in contact with the belt 35 the spindle remains stationary. Also, as previously described in detail, the strand of yarn 78 holds the feeler 60 in its depressed position and the contacts and 86 of switch 70 assume their normally open position. Upon closure of the manually operated switch 19 the circuit to the yarn feed motor 13 is completed to rotate the reel 14 and thereby feed the yarn 78 at a constant rate consistent with the revolutions of the spindle drive motor 36. Simultaneously, with the completion of the circuit to the yarn feed motor 13, the projection 22 at the terminal end of the operating rod 21 of the switch 19 latches behind the plunger 2-3 of the solenoid 24 and is held thereby so long as the strand of yarn 78 remains taut and continuous. The movement of the switch rod 21 is transmitted through cable 26 to move the pulley 31 into engagement with the face of the belt 35 to revolve the spindle 30 and the spool 32 and thus wind the strand of yarn 78 thereon.

The circuits to the yarn feed motor 13 and the spindle drive motor 36 remain effective and the pulley 31 on the spindle 30 remains in rotative contact with the belt 35 so long as the strand of yarn is continuous and holds the feeler 60 in depressed position. However, upon breakage of the strand of yarn 78, the feeler 60 is released and the feeler assembly 69 rotates in a clockwise direction, as viewed in FIG. 4. The vibration inherent in twisting frames also assists in walking the feeler assembly 69 in the clockwise direction as noted and is particularly im portant in that it obviates the use of expensive bearings for the pivot rod 54, which bearings are susceptible to fouling by lint and dirt.

As the left-hand leg 66 of the switch actuator 64 enters the field of the magnet 73 the rotative movement of the feeler assembly 69 is accelerated and the leg 66 is snapped firmly against the face 76 of the magnet 73. The right-hand leg 65 of the switch actuator 64 moves to depress the plunger 72 of the switch 70 in a positive ner to close the contacts 85 and 86 thereof and thereby energizes the control circuit. Completion of the control circuit energizes the solenoid 24 to retract the plunger 23 from its latching position with the projection 22 on the operating rod 21 of the switch 19. Spring 25 then opens the contacts 81 and 82 of the switch '19 to deenergize the circuit to the yarn feed motor 13' and thus stop the yarn feed. Simultaneously with the stoppage of the yarn feed, the springs 33 return the slide 28 carrying the spindle 30 and the spool 32 to their original position with the pulley 31 out of contact with the belt 35, whereupon the spindle 30 will gradually cease revolving. The latter arrangement is employed on twist frames to stop any one spindle without stopping any other spindle. Upon rethreading the strand 78, the idled spindle is set in operation by closing its associated switch 19 as previously described.

It is also obvious that if the yarn feed apparatus 11 overruns the spool 32 and slack develops in the threaded strand 78 the yarn breakage detector 16 will function the same as in the event of a breakage.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred embodiment of the same, but that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claim:

1. Apparatus for winding strand material comprising: a source of strand; powered strand feeding mechanism; a strand receiving spool mounted on rotatable spindle means; driving means for rotating said spindle means; carriage means mounting said spindle means for advance movement toward said driving means to engage and rotate said spindle means and for retraction from the advanced position; resilient means for normally positioning said spindle means out of engagement with said driving means; a feeler member rotatably mounted about an axis and positioned to engage said strand in its path of travel, said feeler member being rotatable about said axis in a first direction by the tension of said strand; a counterpoise positioned about said axis to rotate said :feeler member in a direction counter to said first direction when free from tension of said strand; actuating means engaging co operating means on said carriage means to automatically eifect said retraction, said actuating means being responsive to the counter rotation of said feeler member; and means responsive to said actuating means to stop said feeding mechanism.

2. The apparatus as defined in claim 1, and additional means positioned to accelerate the rotation of the feeler member as it approaches the second position.

3. The apparatus as defined in claim 2, wherein the additional means includes a magnet exerting an attractiv force upon said feeler member.

4. In apparatus for twisting yarn including yarn feeding apparatus powered by an electric motor, a yarn receiving spool mounted on a movable spindle, means including a belt and a second electric motor for rotating said spindle, resilient means for normally positioning said spindle out of engagement with said belt, the improvement comprising a yarn breakage detector including a feeler assembly rotatable about an axis to a depressed position by a force applied by said yarn, means on said feeler assembly providing a rotative force in opposition to and subordinate to said depressive force, a first circuit including a normally open switch, manually operative means for moving said switch to closed position to supply current to said yarn feed motor, mechanical means connected to said switch operating means adapted to move said spindle into contact with said belt upon closure of said switch, a second circuit including a solenoid adapted to retain said first-recited switch in closed position and said spindle in engagement with said belt, normally open switch means in the path of said feeler assembly rendered effective by breakage of said yarn to energize said second circuit and said solenoid thereby deenergizing said first circuit and releasing said mechanical means to permit movement of said spindle away from said belt by said resilient means.

5. Apparatus for winding strand material comprising: a source of strand; powered strand feeding mechanism; a strand receiving spool mounted on rotatable spindle means for rotation therewith; positionable driving means to engage and rotate said spindle means, said driving means being normally positioned out of engagement with said spindle means; a feeler member rotatably mounted about an axis and positioned to engage said strand in its path of travel, said feeler member being rotatable about said axis in a first direction by the tension of said strand and in a direction counter to said first direction when free from tension of said strand; actuating means responsive to the counter rotation of said feeler member to automatically disengage said spindle means from said driving means; and means responsive to said actuating means to stop said feeding mechanism.

References Cited in the file of this patent UNITED STATES PATENTS 1,840,642 Stone Jan. 12, 1932 2,129,639 Adams et a1. Sept. 13, 1938 2,557,783 Cochran June 19, 1951 2,599,595 Wachsman June 10, 1952 2,733,308 Vassen Jan. 31, 1956

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