US3870088A

US3870088A - Apparatus for withdrawing and storing filling yarn in stationary filling supply weaving machines

Info

Publication number: US3870088A
Application number: US363138A
Authority: US
Inventors: Walter Scheffel
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-05-23
Filing date: 1973-05-23
Publication date: 1975-03-11
Anticipated expiration: 1992-03-11
Also published as: FR2185704B3; FR2185704A1; CH562342A5

Abstract

A system whereby a low and uniform withdrawal velocity is obtained at the filling yarn supply unit and a low and uniform withdrawal resistance exists in the filling yarn storage. A cylinder is provided with partitions extending helically around drum means. The cylinder has a perimeter matching the length of filling yarn to be stored around the drum means. The filling supply is storable and releasable under influence of a fluid relative to chambers formed by the partitions.

Description

United States Patent [1 1 Scheffel Mar. 11, 1975 1 APPARATUS FOR WITHDRAWING AND STORING FILLING YARN IN STATIONARY FILLING SUPPLY WEAVING MACHINES [76] Inventor: Walter Scheffel, lndustriestr. 53,

8832 Weissenburg, Germany [22] Filed: May 23, I973 [21] Appl. No.: 363,138

[30] Foreign Application Priority Data May 23, 1972 Germany 2224933 Oct. 9, 1972 Germany 2249393 [52] US. Cl 139/122 R [51] Int. Cl D03d 47/36 [58] Field of Search 139/122 H, 127 P; 226/97, 226/117, 118; 242/182-185 [56] References Cited UNITED STATES PATENTS 3,303,857 2/1967 Scheffel 139/122 Reader 226/118 Brouwer 139/122 Primary E.\'aminerHenry S. Jaudon Attorney, Agent, or FirmWa1ter Becker [57] ABSTRACT A system whereby a low and uniform withdrawal velocity is obtained at the filling yarn supply unit and a low and uniform withdrawal resistance exists in the filling yarn storage. A cylinder is provided with partitions extending helic ally around drum means. The cylinder has a perimeter matching the length of filling yarn to be stored around the drum means. The filling supply is storable and releasable under influence of a fluid relative to chambers formed by the partitions.

10 Claims, 7 Drawing Figures APPARATUS FOR WITl-IDRAWING AND STORING FILLING YARN IN STATIONARY FILLING SUPPLY WEAVING MACHINES This invention relatesto apparatus for withdrawing and storing the filling yarn in machines for making weblike fabrics, such as weaving machines having the filling yarn supply unit outside the shed of warp threads, etc., said apparatus being arranged in the path of the filling yarn-between the filling yarn supply unit and the weaving machine and incorporating at least one mechanicaldrive drum to withdraw the filling yarn from the filling yarn supply unit around which drum the filling yarn is storable and releasable under the effect of a fluid.

It is known in the manufacture of web-like fabrics, such as woven materials, etc., to use machines adapted to work the individual threads into web-like fabrics, such as woven cloths, etc. lnweaving machines, for instance, it is knownto insert filling yarn in a transverse direction between thelongitudinal warp threads and to batten or push the filling yarn in place against the warp threads by means ofa reed. For the purpose of inserting the filling yarn or picking, mechanical conveying means are predominantly used having grippers or carriers for the filling yarn and, depending on the method of propulsion, convey the filling yarn across the full width of the woven material or web-like fabric to be made or over a certain distance after which the filling yarn is picked up by another gripper or carrier to complete the pick. Although the conveying means pick up and insert the filling yarn in the shed of warp threads carefully, the instantaneous pulling moment is liable to cause considerable tension stresses in the filling yarn which, if the filling yarn supply unit fails to yield sufficiently, in particular if the filling yarn is stuck or otherwise fails to unwind, results in the filling yarn breaking. These drawbacks of the direct withdrawal of the filling yarn from the filling yarn supply unit detract from the performance of the machine. Similar drawbacks tend to exist in warp knitting where similarly a filling yarn has to be inserted in order to be worked into the knitted fabric by the individual needles.

In order to overcome these drawbacks, systems have become known that are arranged between the weaving machine and the filling yarn supply unit and designed to withdraw the filling yarn from the filling yarn supply unit before it is conveyed through the warp threads in a mannner that the conveying means need not pull against the resistance of the filling yarn supply unit. Whilst this enables the tension in the filling yarn during its conveyance through the warp threads to be reduced, it will not prevent the filling yarn from whorling or ballooning periodically each time a pick is withdrawn from the supply and inserted in the shed (cf. German Patent Specification No. 817,875).

With a view to avoiding ballooning it is furthermore known to provide a system between the weaving machine and the filling yarn supply unit serving both to withdraw the filling yarn from the filling yarn supply unit and to store it for conveyance through the shed. One such device provides for thefilling yarn to be periodically withdrawn axially towards the front end of the storage winding, although againit will not suppress ballooning. This ballooning of the filling yarn results in stress peaks, although under more readily controllable conditions than where the filling yarn is directly withdrawn from the supply and, in fact, the device referred to fails to achieve its objective, namely to eliminate ballooning. Moreover, systems of this type are very complex, expensive and vulnerable, because they require a system to regulate the length of the filling yarn on the winding element of the storage device (cf. German Patent Specification No. 1,258,809).

Furthermore, there are known systems designed as conveying storage devices featuring tangential filling yarn withdrawal whereby ballooning is avoided, but these systems afford only inadequate withdrawal of the filling yarn from the supply even where considerable energy is appliedQWhere winding on the supply unit is faulty or other obstructions, such as knots, etc., exist in the filling yarn supply, this would cause withdrawal re- I sistances to be set up that the conveying force of the storage device cannot overcome so that the storage will not be completely filled and, consequently, will fail to exercise its tension-reducing effect (cf US. Pat. No. 3,477,476),

Accordingly, the present invention has for its object to provide a system whereby a low and uniform withdrawal velocity is obtained at the filling yarn supply unit and a low and uniform withdrawal resistance in the filling yarn storage. In addition, this invention is intended to solve the problem of withdrawing and storing the filling yarn without ballooning taking place.

This object according to the invention is achieved in a system of the type referred to initially by having a cylinder with a perimeter matching the length of filling yarn to be stored disposed around a drum or drums, the cylinder being provided with partitions extending helically around the drum or drums and the shell of the cylinder being formed with surfaces for the stored filling yarn and ports allowing fluid to escape from the chambers formed in the cylinder by the partitions.

These features afford the advantage that the amount of filling yarn stored is restored after each pick to the same value that is necessary for low-tension insertion of the filling yarn into the fabric to be formed, the action being entirely self-regulating. This is achieved by imparting an initial tension to the helical coil of thread near the outlet of the storage device under the action of a fluid flowing radially outwards from the inside againstthe thread coils. In the coils of the filling yarn lying nearer the inlet of the storage device and those contacting the rotating drum, this initial tension produces a tension that is greater than the initial tension. This physical effect is generally described as the rope friction effect and defined by the following formula:

In this formula S is the thread tension existing at the outlet side in the storage device at the point where the filling yarn just lifts off the rotating drum. S is the thread tension existing at the inlet of the storage device at the point where the filling yarn winds tangentially onto the drum. The value e is the basis of the natural logarithms and u is the friction coefficient for the friction between the filling yarn and the drum. The are measure for the thread length lying on the drum is given by a.

If, for instance, due to the initial tension 5,, the tension S is greater than the withdrawal resistance at the filling yarn supply unit, then the filling yarn is withdrawn from the filling yarn supply and conveyed into the storage device or system. The increase in the amount of thread contained in the storage device causes an increased length of thread to be lifted off under the effect of the fluid and taken towards the envelope of the chamber. Simultaneously, the are a shortens, causing the tension S to be reduced until the filling yarn at the inlet of the storage device soon becomes stationary again. The storage action resides in the fact that the length of filling yarn entering causes the diameter of the'thread coils already contained in the storage device to increase. If a slight pull is exerted on the outlet-side strand of the thread, filling yarn will come out of the storage device, whereby the diameter of the outlet-side thread coils in the storage device will decrease, resulting in a longer thread length contacting the drum than before. The increase in the are a of contact between the thread and the rotating drum or drums produces a higher thread tension 5,. This, in turn, initiates the cycle of conveying and storing already described so that the initial state is soon restored. In other words, the filling yarn in the system according to the invention is not withdrawn against the moment of the filling yarn supply unit but withdrawn from the storage practically without the resistance of an opposing force. These features also go a long way towards preventing breakages of the filling yarn due to the tensions liable to arise with conventional withdrawal systems, thus minimizing disturbances of production. Control of breakages of the filling yarn also prevents knots occurring in the fabric which detract from its quality.

According to a further feature of the invention, the chambers provided around the drum or drums may be disposed helically adjacent to each other.

This helical arrangement of the individual chambers around the drum or drums enables an orderly storage of the filling yarn to be obtained so that it will not tangle inside the cylinder. According to yet another feature of the invention, the edges of the partitions facing the drum or drums are disposed with a clearance between said edges and the drum or drums. This clearance is a special asset where the system is provided with drums arranged to be driven for the purpose of assisting the movement of the filling yarn. In order that the filling yarn can be conveniently withdrawn from the individual chambers, each partition is formed with at least one radial slot for the threading of the filling yarn.

For the purpose of admitting the fluid which, as a rule, will be a gaseous medium, into the cylinder, provision is made for at least one supply pipe for the fluid in the area of the axes of rotation of the drum or drums, the supply pipe being formed with radial outlet ports for the fluid inside the cylinder.

It is within the scope of this invention to arrange the fluid supply pipe either inside the drum or, where several drums are used inside the cylinder, outside the drums.

According to an advantageous improvement of the invention, where several drums are provided, a plurality of fluid supply pipes may be disposed between the drums with their radial outlet ports directed towards the inner surface of the cylinder.

For further advantageous improvements of the invention, reference is made in particular to the remaining subclaims. Two typical embodiments of the invention are shown schematically in the drawing in which:

FIG. 1 shows a cylinder with two drums arranged inside it for a filling yarn to be stored having chambers arranged helically around the drums inside the cylinder,

FIG. 2 is a cross section through FIG. I including a section through one drum.

FIG. 3 is a plan view of the system illustrated in FIG.

FIG. 4 shows a system having only one drum arranged inside the cylinder and chambers disposed in parallel around this drum for the filling yarn,

FIG. 5 is a cross section through the system illustrated in FIG. 4,

FIG. 6 is a plan view of the system illustrated in FIG. 4, and

' FIG. 7 shows a weaving machine with a storage sys tem and filling yarn supply unit arranged at its side.

The system according to the invention is explained and described as applied to the example of a weaving machine it being arranged between a shed of threads 23, a weaving machine 24 and a filling yarn supply unit 25. The weaving machine is provided with insertion means 28 for inserting a filling yarn 26 through the shed of a plurality of warp threads 27. The insertion means 28, which, for example, may be of the mechanical type are shown in the form of tapes arranged on drivable pulleys 29. Each tape end of the insertion means in the embodiment shown here is provided with a gripper or

carrier

30 and 31 for the end of the filling yarn 26, one of the carriers, say 30, being so designed as to not only pick up the end of the filling yarn, but also to transfer it to the other carrier 31. Cutting means 34, for instance, scissors or similar systems, are provided on the weaving machine 24 to cut the filling yarn 26 to length after insertion through the warp threads 27 or a picking at the entry side of the filling yarn into the shed 23. Furthermore, a thread clamp 32 is provided there serving to keep the cutt off filling yarn ready for the insertion of the next pick.

The embodiment of the invention illustrated in FIGS. 1, 2 and 3 is characterized by two rotating drums l and 2 and, arranged helically around these, stationary partitions 3 of a cylinder 33 containing all these elements. The strand 4 of the filling yarn 26 coming from the filling yarn supply unit 25 enters the system at the inlet edge 5. There the filling yarn 26, the strand of which inside the cylinder 33 is designated by 6, runs helically around the drums l and 2. The strand 7 of the filling 26 running to the weaving machine 24 leaves the storage system at the outlet edge 8. It is implied that the strand 4 as well as the strand 7 can also enter and leave the individual chambers 13 through openings in the envelope surface 14 of the cylinder 33. The two drums 1 and 2 rotate in the same sense and are operated by a drive 9. The surface velocity of the individual drums is equal and at least as high as the velocity of the yarn occurring in the strand 7. Through a stationary bearing 10 of the drums l, 2, a fluid, in this case air at above atmospheric pressure, is admitted through an inlet 11 into the drums'to'flow through passages 12 formed as radial holes in the drums into the chambers 13. From the chambers 13 which are formed by the partitions 3 and their outer envelope 14, the air is discharged to atmosphere through the passages 15. The shell of the cylinder 33, Le. its envelope 14, is detachable in order that the filling yarn 26 can be inserted into the storage system before starting operation. The partitions 3 of the chambers 13 surround the drums 1, 2 with a relatively small clearance, a free gap 16 being left free between the partitions and the drums. In this embodiment of the invention, the filling yarn 26 is pulled into the cylinder by rotating drums l, 2 on the one hand and the admission of the fluid, the filling yarn gradually running onto the inner perimeter of the cylinder. In this process, each coil of the filling yarn 26 lies in a separate chamber 13 so that there is no possibility of the filling yarn tangling inside the cylinder 33.

In the embodiment of the invention illustrated in FIGS. 4, 5 and 6, the storage system has been simplified somewhat inasmuch as there is only a single drum 1 instead of two drums l, 2. This embodiment also has the

partitions

17, 18 and 19 of the

chambers

13a and 13b straight around the drum 1 instead of helically. The strand 4 enters through a radial slot 20 provided in the first partition 17 into the chamber 13a. In this chamber 13a, the filling yarn 6 wraps around the drum 1 once and then passes through another slot 21 into the next chamber 13b. The outlet-side strand 7 leaves the chamber 13b through another slot 22 to run on to the weaving machine 24. Similar to the preceding embodiment of the invention it is also implied that the inlet and outlet of the strands 4 and 7 may be through openings in the shell of the cylinder 33. A pressurized fluid, such as air in this case, is admitted through an inlet 11 in the bearing system of the drum 1 to the passages 12 in the drum to flow through these radial passages into the

chambers

13a and 13b which it again leaves through the ports 15 in the shell or envelope 14 of the cylinder 33. The coils formed by the filling yarn 6 around the drum 1 increase in diameter under the influence of the radial flow of the fluid to lie against the inner surface ofthe shell 14. The surface velocity of the drum is constant and at least as high as the maximum velocity of the strand 7 occurring. In the embodiments illustrated the supply of a fluid is represented as being through the individual drums 1 and 2 formed with radial ports 12. In cases where the supply cannot be taken through the drums, it is also possible, especially where several drums are used inside a cylinder 33, to arrange the supply pipes outside the drums, as exemplified by the dashdot line in FIG. 1. In this configuration, the fluid supply pipes are disposed in parallel to the rotating axes of the drums, but they are outside the drums and have their radial ports directed towards the inner surface of the cylinder. The use of such fluid supply pipes can be an advantage especially where radial ports in the drums 1, 2 are to be avoided, or where sealing is a special problem in taking the fluid supply through the drums.

As described in the foregoing, the helical coils of yarn are separated by partitions. This means that a new partition follows after every 360 arc of the yarn winding. Two typical alternatives are described and represented in the embodiments referred to above, namely a parallel arrangement and a helical arrangement of the individual partitions. The parallel partitions are disposed perpendicularly to the axis of the rotating drum and are formed each with a slot shaped radial penetra: tion serving to transfer the filling yarn into the next chamber. If the partition or separating surface is formed as a helical surface, these penetrations are not needed because the partition will then follow the helical yarn coil at a uniform spacing. Between each partition and the next, there is an outer envelope, i.e., the shell of the cylinder which connects the outer perimeter of the chamber. This envelope is permeable and permits the fluid to-escape outwards, while controlling the size of the yarn coils as the filling yarn is laid onto the inside of this envelope. Together with the partitions, this envelope forms the chambers referred to earlier of which each accommodates one coil of yarn. The number of chambers can be chosen at will. It is thus possible to have a group of adjacent chambers handle one yarn and the subsequent chambers another yarn. This results in a storage system according to the invention for multicolour weaving machines. Compared to the storage system according to the invention for storing and conveying one yarn, the multiple version is bigger, but not more complex. Known systems for the same purpose involve a separate additional system for each additional yarn whereby the costs and the complexity increase proportionately. lf filling yarn is withdrawn periodically or cyclically by the weaving machine from the storage system filled according to the method proposed by the invention and, if the stored length of yarn is greater than the length required for a pick, the tension at the outlet of the storage system will be low and uniform. The velocity of thefilling yarn leaving the storage system is determined in the system according to the invention by the weaving machine itself, whereas the velocity of the yarn entering is regulated by a straighforward physical principle in a manner that the storage system is filled up again once a perdetermined length of yarn has been withdrawn. The use of this principle enables a straightforward storage system to be obtained at low cost and with a high efficiency.

What we claim is:

1. Apparatus for weaving machines having a warp shed including means to define a path'and a system for withdrawing and storing of filling yarn in machines for making web-like fabrics with a filling yarn supply being outside the warp shed, said withdrawing and storing system being located in the path of the filling yarn between the filling yarn supply and the weaving machine and incorporating at least one mechanically-driven drum means for withdrawing the filling yarn from the filling yarn supply, the filling yarn being controlled about said drum to be alternately stored and released under the influence of fluid, means including portions having edges arranged to form chambers collectively around the drum means and a cylinder having a shell defining a perimeter matching the length of the filling yarn to be stored around said drum means, siad shell having surfaces to deposit the stored filling yarn and having openings for the discharge of fluid from the chambers formed by the partitions of the cylinder.

2. Apparatus as in claim 1, characterized in that said further means including partitions to form the chambers provided around the drum meansare arranged helically adjacent to each other.

3. Apparatus as in claim 1 characterized in that said edges ofthe partitions facing the drum means surround the drum means with a clearance therebetween.

4. Apparatus as in claim 1 characterized in that each partition has at least one radial cut-out for the threading of the filling yarn.

5. Apparatus as in claim 1 characterized in that said cylinder has openings in its shell for the entry and exit of the filling yarn.

6. Apparatus as in claim 1 further characterized in that the cylinder has radial cut-outs in its outermost partitions of which one is formed as an inlet edge and the other as an outlet edge for the entry and exit of the filling yarn.

9. Apparatus as in claim 8, further characterized in that said fluid supply pipe passes through said drum means when only one drum means is used.

10. Apparatus as in claim 8, further characterized in that said fluid supply pipe is arranged outside said drum means and is located in the cylinder, said fluid supply pipe being provided with radial discharge ports.

Claims

1. Apparatus for weaving machines having a warp shed including means to define a path and a system for withdrawing and storing of filling yarn in machines for making web-like fabrics with a filling yarn supply being outside the warp shed, said withdrawing and storing system being located in the path of the filling yarn between the filling yarn supply and the weaving machine and incorporating at least one mechanically-driven drum means for withdrawing the filling yarn from the filling yarn supply, the filling yarn being controlled about said drum to be alternately stored and released under the influence of fluid, means including portions having edges arranged to form chambers collectively around the drum means and a cylinder having a shell defining a perimeter matching the length of the filling yarn to be stored around said drum means, siad shell having surfaces to deposit the stored filling yarn and having openings for the discharge of fluid from the chambers formed by the partitions of the cylinder.

2. Apparatus as in claim 1, characterized in that said further means including partitions to form the chambers provided around the drum means are arranged helically adjacent to each other.

3. Apparatus as in claim 1 characterized in that said edges of the partitions facing the drum means surround the drum means with a clearance therebetween.

7. Apparatus as in claim 1 further characterized in that each filling yarn includes a thread that has assigned to it at least one chamber with inlet and outlet edges.

8. Apparatus as in claim 1 further characterized in that at least one fluid supply pipe is provided in the zone of rotation of the drum means and that this fluid supply pipe is provided inside said cylinder having radial discharge ports for the fluid.