US2786569A - Strand feeding mechanism - Google Patents

Description

March 26, 1957 K. H. ANDREN ET AL 2,786,569

STRAND FEEDING MECHANISM original Filed April 19, 1951 asf .9a 338W (9 Fri/356V@ /392 seo Vv O O (D Trng/Vf);

STRAND FEEDING MECHANISM Karl H. Andreu, West Allis, Wis., and Charles J. Roach,

Los Angeles, Calif., assignors to Western Electric Coinpany, Incorporated, New York, N. Y., a corporation of New York Original application April 19, 1951, Serial No. 221,911. and this application May 12, 1955, Serial No.

6 Claims. (Cl. 203-156) This invention relates to strand feeding mechanism and more particularly to a capstan for advancing a strand and for retracting the strand to take up the slack therein. This application is a division of the co-pending patent application by K. H. Andren and C. J. Roach, Serial No. 221,911, filed April 19, 1951 on an apparatus for attaching terminals to wires and now Patent No. 2,708,459.

An object of the present invention is to provide a capstan for gripping a strand and advancing it in response to rotation in one direction and releasably gripping a strand to take up the slack therein and to release the strand after the slack has been taken up in response to rotation of a capstan in the reverse direction.

A device illustrating certain features of the invention may include a capstan having a cylindrical periphery for supporting one convolution of a strand thereon and having a plurality of iirst jaws mounted adjacent the periphery thereof for reciprocable movement in an axial direction and stressed for movement in one direction to yieldably press and grip the strand against a plurality of cooperating second jaws on the disc. The strand is guided onto and off of the periphery of the capstan in a predetermined zone and a stationary cam member actuates the first jaws to open position to release the strand in this zone. The second jaws are pivotally mounted on the capstan for oscillatable movement about radially disposed axes and are resiliently urged to a predetermined normal position for cooperation with said first jaws to grip the strand therebetween and to advance the strand in response to rotation of the capstan in one direction. In response to rotation of the capstan in the reverse direction the second jaws serve to releasably grip the strand and move it in a reverse direction to take up any slack therein and the second jaws have eccentrically disposed gripping surfaces which serve to release their grip on the strand after the slack has been taken up and when the stationary strand pulls on the second jaws and causes them to turn on their pivots.

Other objects and advantages of the invention will become apparent by reference to the following detailed description and the accompanying drawings illustrating a preferred embodiment thereof, in which Fig. l is a side elevational view of the capstan with portions of the guide means for directing the strand relative thereto;

Fig. 2 is a plan sectional View of the capstan and associated parts taken on line 2-2 of Fig. 1;

Fig. 3 is an enlarged sectional view of the capstan taken on line 3-3 of Fig. 1;

Fig. 4 is an enlarged fragmentary side elevational view of the capstan; and

Fig. 5 is an enlarged fragmentary plan View of the capstan.

The present capstan 79 is designed to grip and advance a pair of strands of wire 42 in response to rotation of the capstan in one direction and to releasably grip the wires to move them in the opposite direction to take up the slack therein and to release the gripping engagement nited States Patent O therewith when the slack has been taken up in response to rotation of the capstan in a reverse direction.

The wires 42 are withdrawn from supply reels and guided over pulleys 370 and directed tangentially onto and around the capstan 79 and guided tangentially from the capstan onto pulleys 371. After the wires 42 leave the pulleys 371 they are secured to articles and have a tension applied thereto for advancing them as they are unwound from the capstan.

The capstan 79 is in the form of a disc 378 keyed to a drive shaft 375 which is mounted for rotation in supporting brackets 376. The disc has a pair of cylindrical surfaces or shoulders 379 forming drums separated from each other by a central peripheral rib 380 of octagonal shape extending outwardly from the surfaces 379 and having vertical Walls 381. A pair of wires 42 is adapted to engage and be partially wrapped around the drums 379 of the capstan and be moved toward the walls 381 by a plurality of axially reciprocable jaws 383 mounted on opposite sides of the capstan. These jaws 383 comprise rectangular plates 384 mounted in slots 385 in opposite sides of the disc 378 and have Shanks or rods 386 extending axially therefrom, the heads 387 of which are slidably mounted in guide apertures 388 in the disc. Springs 389 interposed between the heads 387 and plates 390 secured to the disc 378, stress the jaws 383 to normal closed posi tions (Fig. 3) in engagement with the plates 390.

ln their closed positions the reciprocable jaws 383 press the wires 42 against the curved surfaces 392 of oscillatable jaws 393 which serve as abutment members and are disposed in slots 394 extending transversely across the rib portion 380 of the capstan. The jaws 393 are mounted for pivotal movement about pins 395 carried by plate 397 which are secured to the capstans by screws 398 and overlie the slots 394 to retain the jaws 393 in position. Springs 396 urge the oscillatable jaws 393 for movement about the pins 395 as viewed in Fig. 5 to normal positions in engagement with one wall of the slots 394.

In response to forward or counter-clockwise rotation of the capstan 79 as viewed in Fig. l the wires 42 are gripped between the reciprocable jaws 383 in their normal closed position and the end of the oscillatable jaws 393 and advanced therewith. In response to the rotation of the capstans in a reverse or clockwise direction the oscillatable jaws 393 are adapted to grip the wires 42 against the reciprocable jaws 383 and cause the wires to be moved therewith until the wires are drawn taut and oier sufficient resistance to overcome the tension of the springs 396 and cause the oscillatable jaws 393 to rock about the pivot pins 395 and release the wires 42. The curved surfaces 392 of the oscillatable jaws 393 are eccentric relative to the pins 395 and are such that as the jaws 393 are moved with the capstans in a reverse direction they will be oscillated about the pins 395 by a drag of the stationary wires and will release their gripping engagement therewith. in other words, as the capstan is rotated in the reverse direction to take up the slack in the wires 42 associated therewith, the Wires are gripped between the jaws 383 and 393 and are moved with the capstan until the slack is taken up and the wires are heid against further movement with the capstan, whereby as the capstan continues its reverse rotation the wires 42 slip relative to the moving jaws 383 but serve to turn the jaws 393 about their pivot pins 39S to positions where they release the wires and no longer grip them against `the jaws 383. The curved surfaces 392 of the jaws 393 are not concentric with the pins 395 but are shaped to provide progressively more clearance between themselves and the associated jaws 383 as the jaws 393 are progressively turned from their normal positions shown in Fig. 5, whereby during the reverse movement of the capstan,

after the slack is removed from the Wires 42, the wires turn the jaws 393 to positions where the clearance between the gripping surfaces of the jaws 393 and 3?3 is suicient to allow the Wires to move freely therebetween.

There are four sets of reciprocable jaws 3S?, and cooperating oscillatable jaws 393 for each side of the capstan disposed equi-annularly about the disc 37S and these eight sets of cooperable jaws are adapted to grip the pair of wires 42 during a major portion of each rotation of the capstan. The reciprocable jaws 3233 are yieldably maintained in their normal closed positions by springs 389 to grip the wires against the ends orthe oscillatable jaws 393 for movement with the capstan, and the reciprocable jaws 383 are moved to open position, to release the wires in the zone where the wires are directed onto and from the drums 379 of the capstan, by the engagement of rollers 400 on the ends of the rods 3% of the jaws 383 with stationary arcuately shaped cam plates 401 disposed at opposite sides of the capstan 79. The cam plates 401 are mounted on a bracket 402 which is attached to a horizontal bar 404 which is supported by the brackets 376.

It will be understood that the shaft 375 has a plurality of capstans 79 secured thereto for feeding a plurality of wires 42 to the apparatus of which the capstan feed is a part and that selectively operable `drive means are provided for rotating the capstans in one direction to advance the wires successively through predetermined distances and for rotating the capstans in the reverse direction to remove the slack in the wires as more fully disclosed in the above-referred-to application.

It is to be understood that the above-described arrangements are simply illustrative of the application of the principles of this invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. In a strand feeding device, the combination of a rotatable capstan for supporting a looped portion of a strand thereon, a plurality of strand gripping means mounted on said capstan in spaced relation to eachv other for yieldably gripping the ystrand to feed it in response to rotation of the capstan in one direction and to take up slack in the strand in response to the rotation of the capstan in the reverse direction and for releasing the strand when the Slack has been taken up and the strand is held against movement, and means for actuating said fstrand gripping means successively to release portions of said strand as the strand gripping means traverse a predetermined zone to permit a portion of the strand to be moved off of the capstan and a portion to be moved thereonto.

2. In a strand feeding device, the combination of a rotatable capstan having a peripheral surface for supporting a looped portion of strand thereon and having means forming abutments disposed transversely of saidl peripheral surface against which said strand may be gripped, a plurality of jaws engageable with the strand and mounted on said capstan for rotation therewith and for movement toward and away from said abutments, resilient means for moving said jaws to a closed position to grip the strand against said abutments for movement with the capstan, and means for moving said jaws from said closed position during a predetermined portion of their rotation with said capstan to release portions of `said strand and permit portions thereof to be moved onto and off of said capstan.

3. In a strand feeding device, the combination of a capstan mounted for rotation and having a peripheral surface for supporting a strand thereon, means on said capstan forming gripping surfaces `disposed transversely of said peripheral surface against which said strand may be pressed, a plurality of jaws mounted on said capstan for rotation therewith and for sliding movement in an Cit axial direction thereon into engagement with the strand, resilient means for moving said jaws axially in one direction to a closed position to grip the strand against said gripping surfaces, and a stationary cam for moving said jaws in the opposite `direction to an open position during a predetermined arcuate movement of the jaws with said capstan to release said strand and permit portions thereof to be moved onto and off of said capstan.

4. ln a device for feeding a strand and intermittently retracting it to remove the slack therein, the combination of a capstan mounted for rotation alternately in opposite directions about an axis and having a peripheral surface tor supporting a strand thereon in spaced relation to said axis, a plurality of jaws mounted on said capstan for rotation therewith and for movement thereon, means for stopping the movement of said jaws in predetermined closed positions in engagement with said strand, resilient means for moving said jaws from open positions to said closed positions, a plurality of abutment members, means mounting said abutment members for movement on said capstan to and from normal operative positions in the path of movement of `said jaws, resilient means for moving said abutment members to said operative positions for cooperation with said jaws in their closed positions for 0ripping lthe strand therebetween to feed the strand in response to rotation of the capstan in one direction and to retract the strand in response to rotation of the capstan in the reverse direction and for releasing said strand when said abutment member is moved from said operative position, said abutment members being moved from said operative positions by the strand during the rotation of the capstan in a reverse direction when the strand is held against movement, and means for moving said jaws to open positions during movement of the jaws with said capstan through a predetermined zone to release portions of said strand and permit portions thereof to be moved onto and off of said capstan.

5. In a device for feeding a strand and intermittently retracting it to remove the slack therein, the combination of a capstan mounted for rotation alternately in opposite directions about an axis and having a peripheral surface for supporting a :strand thereon in spaced relation to said axis, a plurality of jaws mounted on said capstan for rotation therewith and for movement in an axial direction thereon, means for stopping the movement of said jaws in a predetermined closed position in engagement with said strand, resilient means for moving said jaws axially in one direction to said closed position, a plurality of abutment members, means mounting said abutment mem- 'ners on said capstan for pivotal movement about radially disposed axes to and from operative positions in the path of movement of said jaws, means for yieldably retaining said abutment members in said operative position, said abutment members having curved gripping surfaces operable in said operative position to cooperate with said jaws in their closed position for gripping the strand therebetween to feed the strand in response to rotation of the capstan in one direction and to retract the strand in response to rotation of the capstan in the reverse direction and for releasing said strand when said abutment member is moved from said operative position, said abutment members being moved from said operative positions by the strand during rotation of the capstan in a reverse direction when the strand is held against movement, and a stationary cam for moving said jaws to open positions during a portion of their rotation with said capstan to release portions of said strand and permit portions thereof to be moved onto and off of said capstan.

6. in a device for feeding a strand and intermittently retracting it to remove the slack therein, the combination of a capstan mounted for rotation about an axis and having a peripheral surface for supporting a loop of strand thereon in spaced relation to said axis, a plurality of first jaws mounted on said capstan around the periphery in spaced relation to each other on one side of said strand on the capstan for rotation with the capstan and for movement relative thereto to a normal operative position in engagement with said strand, a plurality of second jaws mounted on said capstan around the periphery thereof in spaced relation to each other and in alignment with said first jaws and on the opposite side of said strand for rotation with the capstan and for movement relative thereto to a predetermined closed position in engagement with said :strand for pressing the strand against said rst jaws, means for moving said second jaws on said capstan to open position during movement of said jaws with said capstan through a predetermined zone to release portions of said strand and to permit portions thereof to be moved onto and oi of said capstan, said first jaws in said operative position cooperating with said second jaws in their closed position to grip the strand therebetween to feed the strand in response to rotation of the capstan in one direction and to retract the strand in response to rotation of the capstan in the reverse direction, said first jaws being moved from said operative positions by said strand during the rotation of the capstan in a reverse direction when the strand is held against movement and said rst jaws being operable to release said strand when they are moved from said operative position.

No references cited.

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