US 2936509 A
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May 17, 1960 Filed Oct. '7, 1958 5. M. MARTIN APPARATUS FOR COLLECTING STRANDS 2 Sheets-Sheet l FROM PREVI 0US OPERATION INVENTOR. S. M MART/N BYy/Z ATTORNEY y 1960 s. M. MARTIN 2,936,509
APPARATUS FOR COLLECTING STRANDS Filed Oct. 7. 195a 2 Sheets-Sheet 2 FIG. 5
INVENTOR. S. M. MART/N ATTORNEY .traversing distributor. fly is a relatively simple operation. In the simplest case,
United tates PatentO" APPARATUS FOR COLLECTING STRANDS Samuel Martin, Lntherville, Md., assignor to Western Electric Company, Incorporated, New York, N.Y., a corporation of New York Application October 7, 1958, Serial No. 765,903
3 Claims. (Cl. 28-21) The present invention relates generally to apparatus for collectlng strands, and more particularly to apparatus for collectmg an advancing flexible strand in an overlapping succession of loops of a substantially constant size within a rotating container.
In the manufacture of various types of conductors for the communications industry, it is usually necessary to perform a succession of manufacturing operations involving running lengths of strand or filamentary material of one type or another. During most of the several manufacturing operations, a relatively long length of the strand produced in one operation is taken up, for example, by winding the strand on a takeup reel or by distributing the strand loosely into a take-up receiver, such as a barrel. The take-up member, such as the reel or barrel, is then transported to another location and the strand is withdrawn therefrom as feed or supply to a subsequent strandworking operation.
In many applications, the strand or filament is of a flexible or elastic nature, such as polyvinyl-chloride jacketed cordage used in the manufacture of the spring cords of a modern telephone handset. It is hereby proposed to take up strand material, particularly flexible strands such as polyvinyl-chloride jacketed cordage, in the form of loosely packed loops in a rotating take-up barrel. Preferably, the barrel has a relatively large volume so as to hold a long length of the strand emerging from one operation for ultimate conveyance to a subsequent strand-working operation, where the strand accumulated in the barrel may be withdrawn. This form of barrel take-up is simpler and more convenient to use than a conventional take-up reel, and is preferred in many cases where a flexible strand is involved.
Reel take-ups generally require a variable-speed, closely controlled, relatively high speed drive for the reel, a synchronized, traversing distributor for the strand, and carefully controlled and expensive changeover equipment if 'a high-speed strand is to be shifted from a full reel to an empty reel on the fly.
The barrel take-up herein proposed obviates or simplifies most of the problems just mentioned and results in an economical and easy-tooperate take-up system. The barrel is designed to rotate at a relatively slow speed compared to the speed of the strand or the speed which would be required for a take-up reel. For example, the barrel may rotate at a speed of about 3 rpm. in taking up a strand advancing at about 300500 feet per minute. Further, the barrel rotates at a constant speed throughout the collection operation. In contrast with this, the peripheral speed of the winding surface of a take-up reel must be substantially equal to the strand speed and the rotational speed must be slowed throughout the takeup operation as the winding surface of the reel builds up with the strand.
Also, the barrel take-up described herein requires no In addition, changeover on the an empty barrel is merely being placed on the barrelrotating means displacing a full barrel so that a length of the strand extends between the top of the full barrel and the bottom of the empty barrel.
An object, therefore, of the invention is to provide new and improved apparatus for collecting strands.
Another object of the invention is to provide apparatus for collecting an advancing flexible strand in an overlapping succession of loops of a substantially constant size within a rotating container.
A more specific object of the invention is to provide apparatus for taking up a flexible cordage, such as polyvinyl-chloride jacketed cordage, advancing at speeds of the order of 300-500 feet per minute, in a rotating takeup barrel in the form of an overlapping succession of loops which build up in a series of layers within the barrel and have a substantially constant diameter throughout the collection operation, which diameter is substantially equal to the radius of the barrel.
An apparatus, illustrating certain features of the invention, may include means for delivering a flexible strand downward into a rotating container so that the strand forms an overlapping succession of loops which build up in depth within the container, and means for moving the container end, at least, portions of the delivering means relatively apart at a rate designed to maintain a substantially constant distance between the last point of contact of the strand with the delivering means and the level of the strand within the container.
Preferably, a collapsible guide tube is provided for directing the advancing strand vertically downward into the container, with means provided for collapsing the tube during the collection operation at a rate designed to maintain a substantially constant distance between the lower end of the tube and the level of the strand within the container. The collapsible guide tube may consist of two guide blocks aligned vertically and having a helical spring secured therebetween, coupled with means for moving the lower guide block toward the upper guide block during the collection operation.
Other objects and advantages of the invention will appear from the following detailed description of a specific embodiment thereof, when read in conjunction with the appended drawings, in which:
Fig. 1 is a front elevation of a strand-collection apparatus embodying the invention, with portions broken away to reveal structural details, and showing the posi' tion of a strand guide near the beginning of a collection operation;
Fig. 2 is a top plan view of the apparatus illustrated in Fig. 1;
Fig. 3 is a view of a portion of the apparatus illus trated in Fig. 1, but showing the position of the strand guide near the end of the collection operation;
Fig. 4 is an enlarged vertical section, taken generally along the line 44 of Fig. 3 in the direction of the arrows and illustrating details of a mechanism for moving the strand guide, and
Fig. 5 is a plan view of the strand collected within a container according to the invention, being taken generally along the line 5-5 of Fig. 3 in the direction of the arrows.
Referring now in detail to the drawings, and in particular to Figs. 1 and 2., an apparatus is shown for collecting a flexible strand 10 in an overlapping succession of loops 11-11 (Fig. 5), which build up in depth within a rotating container, such as a circular take-up barrel 12 which rotates about its central axis A. Fig. 1 illustrates ,the barrel 12 near the start of the collection operation,
the letter h.
plied continuously from a previous strand-working operation indicated to be off the page to the right of Fig. 1, such as a plastics extruder.
Means are provided, such as a conventional belt-type capstan designated generally by the numeral 13, for advancing the strand 1% from the previous operation and for discharging the strand downward along a vertical axis B toward the barrel 12. Means are provided, such as a collapsible guide tube designated generally by the numeral 14, for guiding the advancing strand from the capstan 13 into the rotating barrel 12 mounted therebelow. The capstan 13 and the guide tube 14, together, constitute means for delivering the strand downward into the rotating container.
It has been found that when a flexible strand is delivered downward, preferably vertically downward, into engagement with a rotating flat surface, such as the bottom of the barrel 12, the strand 10 will naturally form itself into a succession of generally circular loops 11-11 as the strand contacts the bottom of the barrel 12. If the line of delivery B is displaced from the axis of rotation A of the barrel 12, then the succession of strand loops 11-11 will overlap each other and extend around the bottom of the barrel 12. A preferred pattern of distribution is illustrated in Fig. 5, wherein the strand loops 11-11 have a diameter approximately equal to the radius of the barrel 12.
As the barrel 12 rotates through a second revolution, the strand loops 11-11 then formed are deposited on top of the loops 11-11 formed around the bottom of the barrel 12 during the first revolution. Thereafter, the
overlapping loops 11-11 build up in depth within the barrel 12 in a series of layers until the barrel 12 is filled, substantially as indicated in Fig. 3. After the barrel 12 has been filled to a desired depth, an empty barrel may be substituted therefor and the operation repeated. With this arrangement, the strand 10 may be collected in a continuous succession of barrels Without interrupting the capstan 13 or the previous operation.
The size or diameter of the strand loops 11-11 is primarily a function of three factors: (1) the nature of the strand '10, having particular regard to its flexibility; (2) the speed of advancement or delivery thereof into the barrel 12; and (3) what is termed the unsupportedfall-distance of the strand 10, by which is meant the distance between the last point of contact of the strand with the delivering means (the lower end of the guide tube 14 in the embodiment shown) and the level of the strand within the container. The unsupported-fall-distance is represented in the drawings, Figs. 1 and 3, by The first two factors, the nature and speed of the strand 10, are generally dictated by the previous process and may be regarded as substantially constant for any one system; whereas, the fall-distance h may be regulated to accommodate the particular strand, having regard to the nature and speed thereof, to enable collection of the strand 10 in the form of loops 11-11 of preselected size to enable the most convenient distribution in the barrel 12.
When the unsupported-falldistance "h is relatively large, for instance if there were no guide tube 14 disposed between the capstan 13 and the barrel 12, the diameter of the loops 11-11 is quite large; whereas, the loop diameter becomes progressively smaller as the distance it decreases. It will be seen that if the strand 10 were delivered from a fixed point such as the capstan 13 into the barrel 12, the first layer of the strand loops 11-11 would have a relatively large diameter, while the diameter would become progressively smaller as the strand loops build up in depth within the barrel 12 and the unsupported-fall-distance becomes gradually smaller and smaller.
It has been observed that collection in the form of loops of a variable size is very ineflicient with regard to the amount of strand that can be collected in a given size of barrel. Further, distribution in uneven layers will result causing tangling and uneven pay-01f from the barrel when it is subsequently used as a strand supply. A very efiicient distribution of the strand loops 11-11 into the barrel 12 may be accomplished by initially regulating the unsupported-fall-distance It so that the strand loops 11-11 have a diameter about equal to or slightly less than the radius of the barrel 12, as illustrated in Fig. 5, and then maintaining the unsupported-fall-distance h constant during the entire collection process so that the size of the strand loops 11-11 is maintained substantially constant.
In a similar manner, any other desired constant loop diameter may be provided by initially setting the distance "11 at the value required and then maintaining this value constant as the level of the strand builds up within the container. The step of maintaining the unsupported-falldistance constant may be accomplished, simply, by mov-. ing the barrel 12 and the point at which the strand begins to fall unsupported (the lower end of the guide tube 14) relatively apart at a rate designed to maintain the distance 71 substantially constant. This movement may be accomplished either by moving the barrel 12 downward or by moving at least the lower end of the guide tube 14 upward, and may be accomplished either by hand, regulating the distance it by inspection, or by various mechanisms.
Referring now to the preferred apparatus illustrated in Figs. 1 to 4, inclusive, for practicing the methods of the invention, the capstan 13 includes a positively driven drum 16 and a taut belt 17 passing around a portion of the periphery of the drum 16 and also around portions of the periphery of each of three idler sheaves 18, 19 and 21. The strand 10 is passed in conventional fashion between the belt 17 and the drum 16, being gripped therebetween for advancement as the drum 16 is rotated.
The capstan drum 16 is mounted for rotation at the front of a supporting frame 22, which in turn is mounted cantilever-fashionon a main supporting standard 23. As best seen in Fig. 2, the drum 16 is driven by a motor 24, which is supported on a platform 26 secured in turn to the frame 22. The motor 24 drives a shaft 27 of the drum 16 through the intermission of a belt-and-pulley transmission, designated generally by the numeral 28.
The capstan 13 may be the means for advancing the strand 10 through the previous operation or, conveniently, the previous operation may be equipped with a separate advancing means. In this latter instance, the capstan 13 operates to collect the already advancing strand at the same rate it is being delivered and deliver the same downward into the barrel 12. The' capstan motor 24 is preferably a torque motor synchronizing the speed of the drum 16 with the previous advancing means.
The idler sheaves 18, 19 and 21 are mounted for free rotation at the front of the supporting frame 22 and rotate freely as the belt 17, being advanced by the frictional contact with the drum 16, advances therearound. 'lhe idler sheaves 18 and 21 are so positioned, as viewed in Figs. 1 and 3, that the strand 10 passes in a generally horizontal direction from the previous operation to the drum 16 and is discharged therefrom vertically downward along the line B toward the barrel 12 mounted therebelow.
During the collection operation, the barrel '12 is placed on a turntable 29 for rotation therewith, as illustrated in Fig. 1. The turntable 29 is preferably located, with respect to the position of the capstan drum 16, so that the line of descent B of the stand 10 is oflset from the axis of rotation A of the barrel 12 by a distance substantially equal to one-half of the radius of the barrel 12. With this alignment and with the unsupported-falldistance 11 set so that the loop diameter is approximately equal to the radius of the barrel 12, each loop 11 will lie in an area of the bottom of the barrel 12 between the center thereof and" the inner vertical wall thereof and the overlappingvloops Il -1'1 will occupy an. annular area on the bottom of the barrel 12 having zizwidth approximately equal' to the radius of the barrel The turntable 29 is rotatably mounted on a suitable support 3l and is driven through. abelt-and-pulley transmission, designated generally by the numeral 32, from asuitable motor 33. The turntable 29 and thesupport 31 ,are preferably mounted within a pit in the factory floor, so that the upper surface of the turnable 29 is at floor levelinrorder to facilitate the substitution of a full barrel-for an empty barrel. A particularly advantageous turntable structure is disclosed in my copending application Serial No; 748,745, filed" on July 15, 1958 and entitled Apparatus for Unloading an Article from a Turntable.
That application discloses a turntable having trimmedoif edges disposed so that portions of the barrel overhang the turntable on opposite sides thereof. A plurality of short rollers are mounted in two parallel lines, normally positioned below the level of the turntable. When it is desired'to unload a full barrel from the turntable, the turntable is stopped in an oriented position wherein the overhanging portions of the barrel overlie the rollers, which a're then elevated to lift the barrel off of the turntable and tilted to facilitate discharging of the full barrel.
The spacing between successive loops 11-11 and the amount of: the strand collected in each layer are functions of the speed of rotation of the barrel as compared to the speed of advancement of the strand. This speed-ratio is not critical but, in general, it may be said thatthe barrel rotates rather slowly as compared to the speed of advancement of the strand 10. For example, in taking up polyvinylchloride jacketed cordage, if the strand is advancing at'a speed of the orderof 300-500 feet per minute, then the barrel may conveniently be rotated at about 3 r.p.m.; however, the optimum speed ratios for any given situation are best worked out empirically. The speed ratio may be regulated manually by adjusting the speed of the turntable motor 33 or by any suitable synchronizing mechanism.
The collapsible guide tube 14 includes a helical spring 34, which is secured at its upper end to a stationary guide block 35 and at its lower end to a movable guide block 36, each of the guide blocks 35 and 36 having a central strand-receiving bore 37 formed therethrough. The upper, stationary guide block 35 is secured by means of an arm 38 to the front of the supporting frame 22 in a fixed position near, but below, the capstan drum 16 so that the central bore 37 is directly in line along the delivery axis B with the strand 10 leaving the capstan drum 16. With this alignment, the upper guide block 35 directs the strand 10 down through the center of the helical spring 34, which in effect constitutes an adjustable tubular guide for the strand 10.
The lower, movable guide block 36 is secured by means of a rod 39 to the lower end of a vertically movable carriage 41 for vertical reciprocation with respect to the upper guide block 35. The length and position of the supporting rod 39 are designed so that the central bore 37 of the lower guide block 36 is in vertical alignment along the delivery axis B with the bore 37 of the upper guide block 35, as illustrated in Figs. 1, 3 and 4. With this aligned construction, the strand 10 passes vertically downward through the entire collapsible guide tube 14, including the upper block 35, the spring 34 and the lower block 36, even though the lower block 36 is moved with the carriage 41 toward or away from the upper block 35.
As best illustrated in Fig. 2, the carriage 41 is received in guides 42-42 for vertical sliding movement along the back of the supporting frame 22. A rack 43 is secured in a vertical position to the right-hand side of the carriage 41, as viewed in Fig. 4, and projects out- 6 wardly therefrom in order to mesh with a pinion gear 44. The pinion gear 44is rotated in either a clockwise or a-counterclockwise direction, as viewed in Fig. 4, in order to raise or lower, respectively, the carriage 41 and thus the movable guide block 36 according to the invention.
The lower guide block 36 is elevated during the entire collection operation at a rate designed to maintain the unsupported-fall-distance between the under surface of'th'e lower guide block 36 and the level of the strand 10 in the barrel 12 substantially constant at the value h; This maybe accomplished, simply and effectively, by driving the pinion gear 44 from the capstan motor 24 through intermediate speed-reduction gearing.
In the specific embodiment shown in the drawings, suchinter'mediate gearing includes: a small bevel gear 46" keyed to the opposite end of the drum shaft 27; a large bevel gear 47 which meshes with the gear 46 and is keyed' to one end of a shaft 48; a circular gear 49 keyedt to the' other end of the shaft 48; a movable circular gear 51, which is keyed to a slidable shaft 52 and is positioned during the collection operation so that the movable gear 51v meshes with the gear 49, as shown in Figs. 2 and 4; a circular gear 53 keyed to a shaft 54 and disposed so that the gear 53 meshes with the movable gear 51 when that gear is also in mesh with the gear 49; and the pinion gear 44, which is also keyed to the shaft 54 and drives the rack 43 upward as the capstan drum 16 rotates in a counterclockwise direction, as viewed in Figs. 1 and 3, to advance the strand 10. The shafts 27, 48, 52 and 54' are all journalled in suitable bearing brackets 56-56, which are mounted on and extend upwardly from a horizontal supporting plate 57, which in turn issecured to the frame 22.
When the barrel 12 has been filled and it is desired to substitute an empty barrel therefor, the driving connection between the capstan motor 24 and the rack 43 is removed by disengaging the movable gear 51 from betweenfthe gears 49 and 53. This may be accomplished, simply, by pushing to the right, as viewed in Fig. 2, on ahandl'e 58" of the slidable shaft 52, which then slides in the associated bearing blocks 56-56 until gear 51 is disengaged. When the driving connection is removed, a crank 59 on the shaft 54 is rotated manually in order to turn the pinion gear 44 in a counterclockwise direction, as viewed in Fig. 4, to lower the movable block 36 back to the starting position and establish the initial distance h for the next collection operation. If desired, any suitable stops may be employed to assist in resetting the initial distance h at the desired value.
As indicated by comparing Fig. 1 with 3, the helical spring 34 is quite extended near the start of the strandcollection operation and is quite compressed near the end of the operation. This construction is convenient and efficient, in that the spring 34 in effect forms a tubular guide for the strand 10 over the entire distance between the upper and lower blocks 35 and 36 regardless of the position of the lower guide block 36.
It will be obvious that this invention is not limited to the specific details described in connection with the above embodiment of the invention, but that various modifications may be made without departing from the spirit and scope thereof.
Although the illustrated construction utilizing the collapsible guide tube 14 is highly preferred, since the strand is always guided over substantially the entire distance between the capstan drum 16 and the point of release, it will be realized that various other guiding or delivering mechanisms might be employed, at least the lower end of which would be movable upward during the collection operation in order to maintain the distance h substantially constant. For example, it might be necessary in the case of very fine strands to mount the advancing means, such as nip rollers, within the barrel at the start of the operation and then slowly withdraw the nip rollers from the barrel as the collection operation proceeds. In this instance, no guide member would be utilized, and the nip rollers would be mounted on a movable carriage for vertical movement with respect to the barrel 12.
What is claimed is:
1. Apparatus for collecting an advancing flexible strand in a rotating container, which comprises a collapsible guide tube through which the strand advances, said tube being mounted above the container and substantially vertically in order to guide the advancing strand vertically downward into the container so that the strand forms an overlapping succession of loops within the container which build up in layers of increasing depth as the container rotates, and means for collapsing said tube during the collection operation at a rate designed for maintaining a substantially constant distance between the lower end of said tube and the level of the strand within the container.
2. Apparatus for collecting a flexible strand in a container, which comprises means for advancing the strand vertically downward, a first guide block mounted in a fixed position near said advancing means and having a bore formed therethrough tor receiving the strand as it leaves said advancing means, a second guide block having a strand-receiving bore formed therethrough and mounted in vertical alignment below said first guide block for vertical reciprocation with respect thereto, a helical spring secured between said guide blocks so that the strand advances therethrough, said advancing means and said guide blocks being mounted above the container so that the strand passes through said spring and said guide blocks into contact with the bottom of the container, means for rotating the container whereupon the strand contacting the bottom of the container forms an overlapping s-uccession of loops around the bottom of the container which builds up in layers of increasing depth as the container rotates, said second guide block being initially positioned a predetermined distance h above the bottom of the container, and means for moving said second guide block upward toward sad first block during the collection operation at a rate designed for maintaining the distance between said second guide block and the level of the strand in the constant at the value h.
a 3. Apparatus for collecting a flexible strand in a cireular barrel, which comprises a capstan designed for. advancing the strand and mounted for discharging the strand vertically downward, a first guide block mounted in a fixed position near said capstan and having a bore formedtherethrough for receiving the strand as it'leaves said capstan, a second guide block having a strand-re ceiving bore 'formed'therethrough and mounted in vertical alignment below said first guide block for vertical reciprocation with respect thereto, a helical spring secured between said guide blocks so that the strand advances therethrough, said capstan and said guide blocks being mounted above the barrel so that the strand passes through said spring and said guide blocks into contact with the bottom of the container along a line offset from the axis of rotation of the barrel by a distance substantially equal to one-half of the radius of the barrel, means for rotating the barrel whereupon the strand contacting the bottom of the container forms an overlapping succession of loops around the bottom of the barrel which build up in layers of increasing depth as the barrel rotates, said second guide block being initially positioned a predetermined distance h above the bottom of the barrel selected so that the strand loops have a diameter approximately equal to the radius of the barrel, and means for moving said second guide block upward toward said first block during the collection operation at a synchronized rate designed for maintaining the distance between said second guide block and the level of the strand in the container substantially constant at the value h so that all of the strand loops collected in the several layers have a diameter substantially equal to the radius of the barrel.
container substantially References Cited in the file of this patent UNITED STATES PATENTS 795,980 Hubbard Aug. 1, 1905 FOREIGN PATENTS 14,473 Great Britain or 1894