US3834634A

US3834634A - Method of controlling the knotting procedure in textile machines, particularly automatic winding machines and pneumatic circuit for performing said method

Info

Publication number: US3834634A
Application number: US00095542A
Authority: US
Inventors: J Havlas; P Kostelecky; J Sedlarik
Original assignee: Elitex Zavody Textilniho
Current assignee: Elitex Zavody Textilniho
Priority date: 1970-04-30
Filing date: 1970-12-07
Publication date: 1974-09-10
Anticipated expiration: 1991-09-10

Abstract

Improved method and apparatus for controlling the yarn knotting procedure in textile machines. The invention is particularly adapted for application of winding machines having a source of supply of yarn from which the yarn travels to the winding mechanism, and a knotting mechanism disposed downstream of the winding mechanism. The apparatus includes means for detecting the absence of yarn under tension in a zone downstream of the knotting mechanism, fluid pressure means for initiating the operation of the knotting mechanism, a source of fluid under pressure, conduit means including a valve means selectively connecting the fluid pressure source and the means for operating the knotting mechanism, and means operated by the yarn tension detecting means for operating the valve means to actuate the knotting mechanism.

Description

United States Patent [191 Havlas et a1.

METHOD OF CONTROLLING THE KNOTTING PROCEDURE IN TEXTILE MACHINES, PARTICULARLY AUTOMATIC WINDING MACHINES AND PNEUMATIC CIRCUIT FOR PERFORMING SAID METHOD Inventors: Jiri Havlas; Premysl Kostelecky; Jaroslav Sedlarik, all of Liberec, Czechoslovakia Elitex, Zavody Textilniho Strojirenstvi generalni reditelstvi, Liberec, Czechoslovakia Filed: Dec. 7, 1970 Appl. No.: 95,542

Related US. Application Data Assignee:

Primary Examiner-Stanley N. Gilreath 5 7] ABSTRACT Improved method and apparatus for controlling the yarn knotting procedure in textile machines. The invention is particularly adapted for application of winding machines having a source of supply of yarn from which the yarn travels to the winding mechanism, and a knotting mechanism disposed downstream of the winding mechanism. The apparatus includes means for detecting the absence of yarn under tension in a zone [63] C9timmion'm'part of 33,477 downstream of the knotting mechanism, fluid pressure abandoned' means for initiating the operation of the knotting mechanism, a source of fluid under pressure, conduit [52] i 242/35'6 242/35 means including a valve means selectively connecting [51] i C 35 6 R 36 the fluid pressure source and the means for operating [581 of the knotting mechanism, and means operated by the yarn tension detecting means for operating the valve [56] g gfifg gz means to actuate the knotting mechanism. 2,407,366 9/1946 Cotchett et al. 242/356 R 13 Claims 13 Drawing Figures /4/ I J /4/ Z4'\$///,E-'I [5 i 13 i 74 I402 i I I2 2-. 140/; II I2 J i 1" a: /0 O 0 23 5 9 c o ,////I 5 25 3.aa4.' s34 PATENTED SEP 1 o 1924 sum 2 hr 6 FIG 1A PATENTEU SEP 1 01974 3. 834.834

SHEET 5 BF 6 PATENIED SE? 1 01914 SHEET 8 OF 6 FIG. ll

METHOD OF CONTROLLING THE KNOTTING PROCEDURE IN TEXTILE MACHINES, PARTICULARLY AUTOMATIC WINDING MACHINES AND PNEUMATIC CIRCUIT FOR PERFORMING SAID METHOD This application is a continuation-in-part of application Ser. No. 33,477, filed Apr. 30, 1970 now abandoned.

The present invention relates to a method of controlling the yarn knotting procedure in textile machines, particularly in automatic winding machines, and to a pneumatic circuit for performing said method.

In automatic winding machines hitherto known, knotting of broken yarn ends or in supply cop exchange is performed by means of mechanisms which are controlled by a stop motion. These mechanisms, however, are relatively complicated, require high accuracy of workmanship, and require constant, precise adjustment and maintenance. The intricacy of these mechanisms causes their frequent failure and inaccurate operation.

The present invention has among its objects the mitigation of the said disadvantages and the provision of an apparatus and method in which the knotting of the broken yarn and cop exchange are performed substantially more simply than heretofore.

According to the method of the present invention, a pressure pulse produced by the breakage or absence of the yarn breaks a stop motion; a pneumatic circuit connected to a source of pressure fluid is then energized to actuate a knotting means. The said pneumatic circuit is connected to the pressure fluid source during the whole period of operation of the knotting means. The subject matter of the pneumatic circuit according to the present invention resides particularly inthat it is provided with at least one pneumatic sensor connected to a distributing slide valve which, in turn, is connected to a pressure fluid source. In this manner, the construction of the winding machine becomes very simplified; its productivity is increased, and its attendance and maintenance are very much facilitated.

Further advantages and features of the present invention are described in the following description and shown in the accompanying drawings of an illustrative embodiment in accordance with the invention.

In the drawings:

FIG. 1 is a view partially in elevation and partially in vertical section of the winding head of an automatic winding machine;

FIG. IA is a diagrammatic view in perspective of the knotter of the automatic winding machine and the driving mechanism for the knotter;

FIG. 2 is a diagram of a first embodiment of pneumatic circuit of the winding unit of FIG. 1;

FIG. 3 is a diagram of a second embodiment of pneumatic circuit of the winding unit,

FIG. 4 is a diagram of the drive for the shaft mounting a guide for holding extended the yarn from a replacement cop; 7

FIG. 5 is a vertical section of the stop motion, the parts being shown in full lines in the positions they assume in the absence of a yarn under tension, the parts being shown in dash lines in their yarn-introducing position;

FIG. 6 is a view in vertical section through the yarn brake, the solid lines showing the operating position of the brake, the yarn-introducing position being shown in dash lines;

FIG. 7 is a diagram of a supply yarn guide, the working position being shown in full lines, the yarnintroducing position being shown in dash lines;

FIG. 8 is a view of an extensible guiding eye in its working and introducing positions, the working position being shown in full lines and the yarn-introducing position being shown in dash lines; and

FIG. 9 is a view of an embodiment of the cop plate stop.

FIG. 10 is a view in side elevation of cams. 1403 and I404 and a portion of lever 1406;

FIG. I1 is front view of

cam

1403 and 1404 and a portion of lever 1406; and

FIG. 12 is a view in perspective of the relative arrangement of

levers

1406, 1408, and 1402.

The same elements in the accompanying drawings are marked with the same reference characters.

FIG. I is a diagrammatic view of the winding unit of an automatic winding machine; two supply bobbins are shown on the indexable cop plate 1, the supply bobbin 2 being at the working position and the supply bobbin 2 at the preparatory position. From the supply bobbin 2, the yarn 3 is wound off by means of driven feeding rollers 12 over a balloon limiter 4, a guide 5, a supply stop motion 6, a brake 7, around a guide 8, through an electronic clearer 9, a yarn breakage stop motion 10, and a laterally displaceable guiding eyelet 11. Further, the yarn is drawn through a sensor 13 for checking the pull of a pneumatic injector device 15 and about a gripper 24 above a knotter 14. The gripper 24 and its function have been fully described in U.S. Patent Application Ser. No. 5,334 of HORATSCHKE et al., coassigned to the present assignee, such application having now matured into U.S. Pat. No. 3,643,990, Feb. 22, 1972. Briefly, gripper 24 serves to catch the end of yarn 3 if the latter is interrupted. In the course of the subsequent knotting operation, the length of the yarn 3 extending between the gripper 24 and the storage chamber 16 is moved by elements l4ll to the knotter 14 which connects said length of yarn 3 either with yarn 3 or yarn 3 (depending on the point of breakage of the yarn), the latter being brought to the knotter 14 by means of the lever 23. The pneumatic device 15 charges yarn into a supply or storage chamber 16. Yarn is withdrawn from chamber 16 through a guide 17, a brake 18, a lubricating device 19, :a stop motion 20, a guide 21, and is wound by means of winding drum onto bobbin 22. The supply bobbin 2 has its yarn end 3 held extended by a guide 25, in which said yarn end 3 is firmly held.

The knotter is generally similar to that disclosed in the application of Horatschke et al, Ser. No. 5,334,

filed Jan. 23, 1970, and assigned to the present application.

The movable yarn guide 25, supply stop motion 6, yarn breakage stop motion 10, brake 7, guide 8, electronic clearer 9, guiding eyelet 11 and cop plate 1 are connected to a pneumatic circuit which includes distributing slide valves 31 and 42 (FIGS. 2 and 3) and a pressure fluid source (not shown) connected to the various conduits at each of the locations marked 30.

The supply stop motion 6 and the yarn breakage stop motion 10 are of the same construction. As shown in FIG. 5, each had a swingable yarn sensor 61 in the form of a first class lever mounted swingably on a holder 62,

assignee of the a power unit 63 and a pneumatic sensor 64 being attached to said swingable sensor 61. The two mentioned units are arranged on the side of the swingable sensor 61 opposite to the arm thereof, which contacts yarn 3. To the swingable sensor 61, a piston 641 in body 64 of the pneumatic sensor 64 is operatively connected, the piston 641 forming part of a valve which opens upon reaction of the stop motion to absence of yarn. The

stop motions

6 and 10 are shown and claimed in application Ser. No. 2,927, filed Jan. 14, 1970 now abandoned, of Kostelecky et al. and assigned to the assignee of this application.

Upon the opening of the

valve

64, 641 fluid under pressure is fed to distributing slide valve 31 through conduit 30A (FIGS. 2 and 3) a

piston mechanism

631, 632 of the power unit 63 (FIG. 5) being traversed in cooperation with the change of the working position of said piston 641; said power unit 63 is provided with a sensing element 633, which cooperates with the said swingable sensor 61. The

piston mechanism

631, 632 of the power unit 63 is provided with a reversing element, e.g., a coil compression spring 630 for opposing downward travel of piston 631.

Brake 7 is shown in FIG. 6. Its outer plate 71 is connected by means of a tie rod 72 with a power unit 70. The end of said tie rod 72 is chamfered and mounted adjacently to key 73, with which the power unit 70 is provided. Reciprocation of the piston rod of power unit 70 causes tie rod 72 to rise and fall.

The power unit 70 of brake 7, power unit 110 of the extensible guiding eyelet 11, the power unit 250 of the extensible yarn guide 25 for yarn 3, the power unit 43 of cop plate 1, and the power unit 440 for pin 44, which serves to stop the cop plate 1 in position, are all made in the same manner as the power unit 63 of yarn breakage stop motion 6 and supply stop motion 10.

The movable guiding eyelet 11 (FIG. 8) is mounted directly on the piston rod of the power unit 1 10. Pin 44 for stopping the cop plate 1 is directly fastened to the piston rod of the power unit 440 (FIG. 9).

The power unit 250 of the extensible yarn guide 25 (FIG. 7) is provided with a yarn introducing fork 251. Fork 251 introduces yarn 3 into the path of the yarn introducing lever 23, which is provided with a known means 252 for gripping the yarn. Yarn 3 is held at the introducing fork 251 by means of a suction nozzle (not shown). Alternatively, it is also possible to transfer yarn 3 from the supply bobbin 2 manually to the introducing fork 251 and to secure it on the introducing fork, for example, by winding the yarn therearound. When the stop-motion 6 responds to the breakage of yarn 3, yarn 3 is advanced by means of the introducing fork 251 of the guide 25 into the path of the lever 23. Lever 23 is disclosed in US. Application Ser. No. 889,850, filed Dec. 15, 1969, now US. Pat. No. 3,587,990 coassigned to the present assignee.

The above-mentioned guiding eyelet 11 in the solidline position thereof shown in FIG. 8 guides the yarn 3 into the nip ofa pair of feeding

rollers

12, 12; the relationship between the guiding eyelet 11 and the feeding rollers 12, 12' is more clearly shown in FIG. 1. Upon breakage of the yarn 3, the responding stop-motion or sensing device causes the guiding eyelet 11 to be advanced into the position shown by the broken lines in FIG. 8, so that the eyelet 11 can catch the yarn 3 or yarn 3 being introduced by the lever 23. After the knotting of the yarn, the guiding eyelet 11 after the bleeding of the power unit 110 thereof returns by the action of a spring into its position shown in solid lines. The guiding eyelet 11 is also advanced into the broken-line position independently of a breakage of yarn 3, in the case wherein the storage chamber 16 is completely filled with yarn 3. This is necessary because the feeding

rollers

12, 12 feed the yarn 3 at a speed higher than that of the withdrawal of the yarn 3 from the storage chamber 16. The connection between the storage chamber 16 and the guiding eyelet 11 has been indicated by a broken line in FIG. 1; the structure of such connection is disclosed in US. Pat. Application Ser. No. 2,571 filed Jan. 13, 1970, now US. Pat. No. 3,673,649.

A power unit 43 (FIGS. 2 and 3) is connected with the cop plate 1 by means of a suitable chosen transmission mechanism, which is not shown in the accompanying drawings. Such transmission mechanism indexes the cop plate 1 to advance the reserve 2 into the working position; the mechanism may be similar to that shown in the application of Kostelecky et al., Ser. No. 5,247, now US. Pat. No. 3,617,011, filed Jan. 23, 1970, assigned to the same assignee as the present application.

The power units 63 of the supply stop motion 6 and of the yarn breakage stop motion 10, and the power unit of brake 7 are connected to the pneumatic circuit through a distributor 37 (FIGS. 2 and 3). Working cylinder 36 is connected to distributor 37 and also to slide valve 31 which connects them either with the atmosphere by means of opening 40 or with the pressure fluid source 30. The left side of the distributing slide valve 31 which is provided with throttle valve 39, is connected to the pneumatic sensor 64 of the yarn breakage stop motion 10. The right side of distributing valve 31 is provided with a reversing element, a coil compression spring 38, mounted onto the piston rod 32 of the slide valve 31. The piston rod 32 engages with one of its ends the recess of the rotatable stop plate 33, the switch 34 of a solenoid valve 35 being attached to the other end of the piston rod, said solenoid valve 35 controlling the bypassing of the pressure fluid from the source 30 into the power unit of the extensible guiding eyelet 11 (FIG. 8).

The stop plate 33 is mounted on the shaft 60, which is connected by means of a

gear train

610, 620, 630, 640 with a driving means (not shown), the transmission of the torque from gear 640 onto the shaft 60 taking place only after gear 630 on piston rod 41 is moved by means of the working cylinder 36 into engagement with the constantly rotating gear 640 and gear 620, as shown in FIG. 4.

The yam-introducing lever 23 is affixed to the shaft 60 beside stop plate 33; cams (not shown) controlling the gripper 24, for gripping the yarn end 3; feeding forks 141 for feeding said yarn 3 into the knotter 14 are affixed to shaft 60. Also affixed to shaft 60 are cams 1403 and 1404 (FIG.1A) for driving and controlling the knotting mechanism.

Cams 1403, 1404 (FIG. 1A) are fixed on the shaft 60 (FIG. 1). Their circumferences are engaged by two arms of a three-armed lever 1406 which is rotatably mounted, by means of a hole 1405, on a pin (not shown) fixed on a suitable supporting part of the machine. The third arm of the three-armed lever 1406 is movably connected to a lever 1408 by means of a pin 1407 slidable in a slot (not shown) provided in the lever 1408. The lever 1408 is fixed on a pin 1409 one end of which is rotatably mounted in a supporting part of the machine; to the other end of pin 1409 a lever 1402 is fixed in the forked end of which a pull rod 1401 of the knotter 14 is disposed. The knotter 14 is attached to a supporting part 1412 on the machine, for example, by means of a clamp 1410 and screws 1411.

In the system of FIG. 2, the pneumatic sensor 64 of yarn breakage stop motion 6 is connected to the left side of slide valve 42; such valve is provided with a throttle valve 46 discharging to the atmosphere. The power unit 440 for the stop pin 44 for the cop plate 1 is also connected to the left hand end of valve 42, which is connected to the pressure fluid source 30. The slide valve 42 is so constructed as to connect, after its movable valve element has moved to its extreme right position, the power unit 250 of the guide 25 for yarn 3 and the power unit 43 for indexing the cop plate 1 with the pressure fluid source 30. For the purpose of returning the distributing slide valve 42 into the initial position, the right side of valve 42 is advantageously connected by a branch conduit 45 with the power unit 43 for indexing cop plate 1 by means of the pressure space 48, which was formed upon the working stroke of power unit 43.

The connection of the power unit 440, the stop pin 44 and the left side of slide valve 42 with the surrounding atmosphere is performed by means of a reduction valve or throttle port 46. The connection of the power unit 43 of cop plate 1 and power unit 250 of the guide 25 for yarn 3 is performed by branch conduit 47 through the distributing slide valve 31 at its basic positlon.

It is possible to perform the connection only with one stop motion, e.g., the yarn breakage stop motion 10, if the supply cop 2 is changed upon any yarn breakage. Then the power unit 440 for the stop pin 44 and the distributing slide valve 42 are connected directly to the yarn breakage stop motion 10, at the same connection of the other parts of the circuit, the function of slide valve 42 being taken over by slide valve 31, modified to provide it with a corresponding bypassing channel for connecting the power unit 250 and the power unit 43 of copy plate 1 with the pressure fluid source 30.

The system of FIGS. 1, 1A, and 2 described above works as follows:

When no breakage of the wound yarn 3 occurs, the pneumatic circuit is disconnected from the pressure fluid source 30 and is connected with the ambient atmosphere. The power units hold in working position the working points connected to the pneumatic circuit, i.e., stop

motions

6, 10, the brake 7, the laterally movable guiding eyelet 11. The cop plate 1 is stopped with cop 2 in working position, and the guide 25 holds yarn 3' out of the path of the introducing lever 23, which is in its initial position (FIG. 1) and is secured by means of the insertion of an end of piston rod 32 of slide valve 31 into a radial slot in stop disc 33, as shown. Yarn 3 is rewound from the supply cop 2 to bobbin 22, there being maintained a constant supply of yarn 3 in supply chamber 16. If in this situation yarn breakage takes place for any reason between the brake 7 and the feeding rollers 12, the pneumatic sensor 64 of stop motion 10 records its reaction to the absence of yarn 3, and the pressure fluid is thereupon bypassed from source 30 to the left side of the bypassing slide valve 31. By pressure valve 31 is displaced to the right against the force of spring 38; this retracts rod 32 from the radial seat in the stopped disc 33. Simultaneously, by means of microswitch 24, the solenoid valve 35 is operated so as to connect the power unit of the guiding eyelet 11 with the pressure fluid source 30.

The guiding eyelet 11 is thus slid out into position in which it introduces yarn between feeding rollers 12. Upon displacing the slide valve 31, the pressure fluid source 30 is connected with the working cylinder 36, which is thereby displaced against the force of spring 41and thrusts the gear 630 into engagement with the

gears

640 and 620, thus starting the knotting

mechanisms

14, 24, 141, the yarn-introducing lever 23, and the stop disc 33. The working cylinder 36 works simultaneously as a bypassing slide valve which after performing its operating stroke makes the pressure fluid bypass through distributor 37 into the power units 64, the

stop motions

6, 10, and brake 7, thus securing their opening into their yarn-introducing position. The introducing lever 23, which moves in the direction S (FIG. 1), grips the yarn 3 between the guide 5 and the stop motion 6. The other end of yarn 3 is fastened in the gripper 24, the winding process being carried on from the supply accumulated in the supply chamber 16. The lever 23 carries on its motion in the direction S and introduces the yarn 3 from the supply cop 2 into the stop motion 6, brake 7, guide 8, electronic clearer 9, stop motion 10, movable guiding eyelet ll, beside rollers 12 through the sensor 13 for checking the yarn pull, the pneumatic device 15 into the knotter 14, where the yarn ends are knotted together by the mechanism shown in FIG. 1A.

The mechanism shown in FIG. 1A operates as follows: Upon starting the knotting operation, the shaft 60 together with

cams

1403, 1404 start to rotate in the direction S The

cams

1403, 1404, due to their shape, deflect the three-armed lever 1406 first in the direction 5,. This motion of the three-armed lever 1406 is transmitted, by means of the pin 1407, the lever 1408, and the pin 1409, onto the lever 1402 which swings out in the direction S and displaces the pull rod 1401. Such displacement of the pull rod 1401 actuates the mechanisms (not shown) of the knotter 14, and the thread is knotted (a knot is tied). By a reverse motion of the three-armed lever 1406, determined by the shape of the

cams

1403 and 1404, the described mechanism shown in FIG. 1A and the knotter 14 return into their initial position.

After knotting, the lever 23 relleases the new yarn now designated 3, and swings the lever back into the initial position. During the time before attaining said position, the bypassing slide valve 31 is stopped by disc 33, and the

stop motions

6, 10, the brake 7, and the extensible guiding eyelet 11 are held in the yarnintroducing position. Thus, the supply of pressure fluid from the pressure fluid source 30 into slide valve 31 is interrupted. As soon as the introducing lever 23 and the stop disc 33 attain their initial position, the piston rod 32 of the distributing slide valve 31 is thrust to the left by means of spring 38 to engage the recess or seat in the stop disc 33, whereupon the distributing slide valve 31 returns to its initial position and the stop disc 33 is secured against rotary motion. The pressure fluid supplied by the pneumatic sensor 64 of stop motion 6 into the slide valve 31 escapes through the throttling opening 39 into the ambient atmosphere. After stopping the disc 33, the microswitch 34 disconnects the guiding eyelet 11 through the solenoid valve 35 from the pressure fluid source 30, and deaerates its power unit 110, which returns the guiding eyelet 11 with the yarn 3 into the operative position. The space of the working cylinder-slide valve 36 is connected by the channel 40 of the distributing slide valve 31 with the ambient atmosphere, and the piston of the working cylinder 36 is returned by means of spring 41 into its original position, thus disconnecting the drive of the knotting mechanisms. Simultaneously, stop

motions

6 and 10, and brake 7 are returned into their working positions, the

power units

64, 70 of which have been connected through the space of working cylinder 36 by the channel 40 of the distributing slide valve 31 with the ambient atmosphere and are deaerated.

In the case of exhausting the supply winding 2 or of yarn breakage in advance of stop motion 6, the pneumatic sensor 64 of stop motion 6 interconnects the pressure fluid source 30 with the distributing slide valve 42, which is thereupon displaced and connects the pressure fluid source 30 with the power unit 43 of cop plate 1 and the power unit 250 of guide 25. Thereby the replacement of supply cop 2 by cop 2' is effected, the yarn 3' is guided into the path of the introducing lever 23. Simultaneously with the displacement of the piston of slide valve 42, the cop plate 1 is released by retracting stop pin 44 of the power unit 440. Immediately after the reaction of the supply stop motion 6 to the absence of yarn 3, stop motion 10 also reacts to absence of yarn, said stop motion bringing into operation the knotting

mechanisms

14, 24, 141, the stop disc 33, and the introducing lever 23, and interconnecting through the distributing slide valve 31 the

power units

64, 70, 110 with the pressure fluid source 30.

After finishing the exchange of the supply cop, the power unit 43 of cop plate 1 is in such a position that the other side of the distributing slide valve 42 is connected with the pressure fluid source 30. In view of the fact that the supply stop motion 6 has, due to its introducing position, already interrupted the supply of pressure fluid from source 30 through power unit 64 into slide valve 42, displacement of the said slide valve 42 into its original position takes place. The escape of the pressure fluid from the distributing slide valve 42 is provided by means of a suitably dimensioned throttle opening 46. Upon displacement of slide valve 42, the supply of pressure fluid from source 30 into power unit 43 of cop plate 1 is again shut off. After knotting the yarn ends, as soon as introducing lever 23 and the stop disc 33 attain the initial position, the power unit 43 is deaerated by channel 47 through the distributing slide valve 31, whereupon the power unit 43 returns into its initial position. After returning the piston of the pneumatic cylinder 43 into the initial position, the channel 45 is deaerated through the space 48 of the power unit 43 and the opening 49.

It will be understood from the above that the absence of the yarn 3 between the feeding rollers 12, 12' and the bobbin 2 is always detected by the stop-motion or sensing device 10, whereas the stop-motion 6 responds only to the absence of the yarn 3 between the yarn brake 7 and the bobbin 2. Consequently, when breakage of yarn 3 occurs between the yarn brake 7 and the feeding

rollers

12, 12, yarn 3 will be knotted because the length of yarn 3 remains extended between the yarn brake 7 and the bobbin 2 until the stop-motion 10 responds correspondingly, whereby the stop-motion 6 is held in its working position and thus cannot respond to the breakage which occurred downstream of the brake 7. Upon response of the stop-motion 10, lever 23 is actuated to grasp the yarn 3 and the stop-motion 6, the brake 7, and other parts are reset into the yarnintroducing position.

A change of the bobbin 2 for bobbin 2 and the introduction of yarn 3 every time the yarn 3 breaks are necessary only with the embodiment of the invention having a single stop-motion device, as has been explained. However, when two stop-motions are provided, then the introduction of yarn 3 upon every yarn breakage would not be advantageous.

FIG. 3 illustrates a modification of the abovedescribed embodiment of FIG. 2. In FIG. 3

amplifiers

50, 51 of the pressure pulse are inserted between the pneumatic sensors 64 of the yarn breakage stop motion 10 and the supply stop motion 6 and the

slide valves

31, 42 attached thereto. Also, by using an amplifier of pressure pulses, or a converter 52, it is possible to connect the solenoid valve 35 controlling the power unit 110 of the extensible guiding eyelet 11 to the distributor 37.

The pneumatic circuit of FIG. 3 operates as follows:

In the case of yarn breakage between the brake 7 and the feeding rollers 12, the pneumatic sensor 10 records its reaction as to the absence of yarn 3 and emits a pressure pulse into the amplifier 50, which makes the pressure fluid bypass from the source 30 to the left side of slide valve 31. The distributing slide valve 31 is displaced, and thus its piston rod 32 releases the stop disc 33. The displaced distributing slide valve 31 interconnects the pressure fluid source 30 with the working cylinder-slide valve 36, which brings into motion the knotting

mechanisms

14, 24, 141, the stop disc 33, and the introducing lever 23, and bypasses the pressure fluid through distributor 37 into the power units 64 of

stop motions

6 and 10 and the power unit of brake 7, thus opening brake 7 into its yarn-introducing position. Simultaneously, upon lifting the stop motions 6 and 10', the pressure fluid from the distributing chamber 37 flows into converter 52, which secures through solenoid valve 35 the extension of guiding eyelet 11 into a yarnintroducing position, the supply of pressure fluid into amplifier 50 is interrupted, said amplifier interrupting the supply from the pressure fluid source 30 into the slide valve 31 and deaerating it simultaneously. The position of slide valve 31 is determined by turning the stop disc 33 into its displaced position, when said disc is not returned into its initial position. After turning the stop disc 33 when yarn knotting has taken place, tie rod 32 is pressed by spring 38 into the recess of the stop disc 33, whereupon the distributing slide valve 31 is returned into its original position, and the space of the operating cylinder 36 is connected through the channel 40 of the distributing slide valve 31 with the ambient atmosphere. The piston 36 then returns by means of spring 41, thus stopping the drive of the knotting

mechanisms

14, 24, 141. Simultaneously, stop

motions

6, 10, brake 7, and guiding eyelet 11 return into their operating positions.

When the supply cop 2 is wound off or the yarn 3 is interrupted in advance of stop motion 6, said stop motion emits, after reacting to the absence of yarn by the pneumatic sensor 64, a pressure pulse into the amplifier 51, which bypasses the pressure fluid from the source 30 into the slide valve 42, whereupon the distributing slide valve 42 is displaced in such manner, that the pressure fluid source 30 is interconnected with the power unit 43 of cop plate 1, thereby substituting supply cop 2 for supply cop 2. Simultaneously, power unit 250 of guide brings yarn 3 into the path of the introducing lever 23. Simultaneously, with the displacement of distributing slide valve 42, the cop plate 1 is released by means of power unit 440 for stop pin 44. After the reaction of stop motion 6 to the absence of yarn, stop motion 10 reacts in the same manner, and brings into motion, in the manner already specified before, by means of amplifier 50 the knotting

mechanisms

14, 24, 141, the stop disc 33, and the introducing lever 23, including the connection of the pressure fluid source 30. After finishing the exchange of the supply cops 2, 2, the power unit 43 of cop plate 1 is in such a position that the distributing slide valve 42 is connected with pressure fluid through channel 45. In view of the fact that the stop motion 6 hasalready interrupted, in consequence of its yarn-introducing position, the pressure pulse into amplifier 51, whereupon said amplifier has interrupted the supply of the pressure fluid from source into slide valve 42, the distributing slide valve 42 is displaced into its original position. The amplifier 51, after interrupting the supply of pressure fluid into the distributing slide valve 42, interconnects them with the ambient atmosphere. Thereupon the supply of pressure fluid from the source 30 into the power unit 43 of cop plate 1 is reestablished. After knotting the broken yarn 3, the power unit 43 is deaerated through channel 47 by way of slide valve 31 which thus returns into its original position. After returning the power unit 43 into the original position, the channel 45 is deaerated through the power unit 43 by way of opening 49.

Although the invention is illustrated and described with reference to a plurality of preferred embodiments thereof, it is to be expressly understood that it is in no way limited to the disclosure of such a plurality of pre ferred embodiments, but is capable of numerous modifications within the scope of the appended claims.

What is claimed is:

1. In a textile machine having yarn winding mecha nism, a source of supply of yarn from which the yarn travels to the winding mechanism, and a knotting mechanism disposed downstream of the winding mechanism, the improvement which comprises means detecting the absence of yarn under tension in a zone downstream of the knotting mechanism, fluid pressure means for initiating the operation of the knotting mechanism, a source of fluid under pressure, conduit means including a valve means selectively connecting the fluid pressure source to the means for initiating the operation of the knotting mechanism, and means operated by the yarn tension detecting means for operating the valve means to initiate the operation of the knotting mechanism.

2. A textile machine according to claim 1, comprising indexable means for supporting the source of yarn supply and a replacement source of yarn supply, means for indexing the supply supporting means, and means responsive to actuation of the means for detecting the absence of yarn under tension for indexing the supply supporting means to advance the replacement source of yarn supply into working position.

3. A textile machine according to claim 2, comprising fluid pressure power means for indexing the supply supporting means and valve means for selectively connecting said fluid pressure power means to the fluid pressure source.

4. A textile machine according to claim 3, comprising means actuated upon the advancing of the replacement source of into working supply intoworking position to feed the yarn from the replacement source to the knotting mechanism, and means selectively connected to said fluid pressure source for operating the last-named means.

5. A textile machine according to claim 1, comprising a yarn feeding means disposed downstream of the knotter, and a selectively actuated yarn brake disposed downstream of the yarn feeding means, and wherein the means detecting the absence of yarn under tension is disposed between the yarn brake and the yarn feeding means.

6. A textile machine according to claim 5, comprising a second fluid pressure power means for actuating the yarn brake and means including the valve means selectively connecting the fluid pressure source to the means for initiating the operation of the knotting mechanism for energizing the second fluid pressure power means.

7. A textile machine according to claim 6, comprising a yarn feeding means, and a laterally movable guide disposed downstream of the yarn feeding means for selectively guiding the yarn into and out of the yarn feeding means, a third fluid pressure power means for actuating the guide, and means including the valve means selectively connecting the fluid pressure source to the means for initiating the operation of the knotting mechanism for energizing the third fluid pressure power means.

8. A textile machine according to claim 2, comprising a yarn brake, and wherein the means for detecting the absence of yarn under tension is disposed between the yarn brake and the yarn supply source.

9. A textile machine according to claim 8, wherein the yarn supply is indexable, and comprising fluid pressure operated means for operating the indexable yarn supply support, fluid valve means operated by the yarn tension detecting means, and conduit means connecting the last-named fluid valve means to the means operating the indexable support.

10. A textile machine according to claim 5, comprising an indexable yarn support, a second means detecting the absence of yarn under tension disposed between the yarn supply and the yarn brake, fluid pressure means operative to index the yarn support, conduit means connecting the second detecting means to the means indexing the yarn support, and pressure pulse amplifiers connected between the first and second ten sion detecting means and the respective devices which they operate.

11. A method of controlling the knotting procedure in a textile machine having a yarn breakage stopmotion and a knotting mechanism, particularly automatic winding machines, comprising emitting a fluid pressure pulse upon reaction of the yarn breakage stopmotion as to absence of yarn, energizing by said pulse means for interconnecting a pneumatic circuit with a pressure fluid source, and operating by fluid pressure from said pressure fluid source the knotting mechanism upon energization of the interconnecting means, and disconnecting said pneumatic circuit from the said pressure fluid source after the period of time necessary to perform said knotting operation.

12. A method as claimed in claim 11, comprising by the action of the pressure fluid of the pneumatic circuit interrupting the pressure pulses of the supply stoprnotion, wherein the textile machine has a cop plate supporting at least one cop and one unwinding cop and a power unit for operating the cop plate, and upon emission of said pressure pulse interconnecting the power unit of the cop plate with the source of pressure parts into the yarn-introducing position.

Claims

1. In a textile machine having yarn winding mechanism, a source of supply of yarn from which the yarn travels to the winding mechanism, and a knotting mechanism disposed downstream of the winding mechanism, the improvemEnt which comprises means detecting the absence of yarn under tension in a zone downstream of the knotting mechanism, fluid pressure means for initiating the operation of the knotting mechanism, a source of fluid under pressure, conduit means including a valve means selectively connecting the fluid pressure source to the means for initiating the operation of the knotting mechanism, and means operated by the yarn tension detecting means for operating the valve means to initiate the operation of the knotting mechanism.

10. A textile machine according to claim 5, comprising an indexable yarn support, a second means detecting the absence of yarn under tension disposed between the yarn supply and the yarn brake, fluid pressure means operative to index the yarn support, conduit means connecting the second detecting means to the means indexing the yarn support, and pressure pulse amplifiers connected between the first and second tension detecting means and the respective devices which they operate.

11. A method of controlling the knotting procedure in a textile machine having a yarn breakage stop-motion and a knotting mechanism, particularly automatic winding machines, comprising emitting a fluid pressure pulse upon reaction of the yarn breakage stop-motion as to absence of yarn, energizing by said pulse means for interconnecting a pneumatic ciRcuit with a pressure fluid source, and operating by fluid pressure from said pressure fluid source the knotting mechanism upon energization of the interconnecting means, and disconnecting said pneumatic circuit from the said pressure fluid source after the period of time necessary to perform said knotting operation.

12. A method as claimed in claim 11, comprising by the action of the pressure fluid of the pneumatic circuit interrupting the pressure pulses of the supply stop-motion, wherein the textile machine has a cop plate supporting at least one cop and one unwinding cop and a power unit for operating the cop plate, and upon emission of said pressure pulse interconnecting the power unit of the cop plate with the source of pressure fluid, by means of which a supply cop change is performed.

13. A method as claimed in claim 11, wherein the textile machine includes a pneumatically operated unit having working parts movable from a yarn break position to a yarn-introducing position and vice-versa the yarn being adapted to be introduced by said unit into a knotting mechanism wherein in said yarn-introducing position, and by action of the pressure fluid connecting the unit to the pneumatic circuit to bring the working parts into the yarn-introducing position.