US3370617A

US3370617A - Device for storing a length of weft and introducing it into a shed

Info

Publication number: US3370617A
Application number: US506047A
Authority: US
Inventors: Strake Lambertus Te
Original assignee: Strake Maschf Nv
Current assignee: Machinefabriek L te Strake NV
Priority date: 1964-11-03
Filing date: 1965-11-02
Publication date: 1968-02-27
Anticipated expiration: 1985-02-27
Also published as: DE1277162B; NO120023B; CH437164A; BE671449A; SE302436B; NL6412787A; FR1552780A; GB1130502A; NL6502156A

Description

Feb. 27, 1968 1. TE STRAKE 3,370,617

DEVICE FOR STORING A LENGTH OF WEFT AND INTRODUCING IT INTO A SHED Filed Nov. 2., 1965 2 Sheets-Sheet 1 Feb. 27, 1968 TE STRAKE 3,370,617

DEVICE FOR STORING A LENGTH OF WEFT AND INTRODUCING IT INTO A SHED Filed Nov. 2. 1965 2 Sheets-Sheet 2 United States Patent OfiFrce 3,379,617 Patented Feb. 27, 1968 3,370,617 DEVICE FOR STORING A LENGTH OF WEFI AND INTRODUCHNG IT INTO A SHED Lambertus te Stralre, Deurne, Netherlands, assignor to N.V. Machinefabriek L. te Strake, Deurne, Province of North-Brabant, Netherlands, a Dutch company Filed Nov. 2, 1965, Ser. No. 506,047 Claims priority, application Netherlands, Nov. 3, 1964, 6412,787; Feb. 19, 1965, 652,156 5 Claims. (Cl. 139-127) ABSTRACT OF THE DISCLOSURE A device for storing a length of weft thread and introducing it into a shed, comprising a shaft adapted to take up by suction a measured length of thread in the form of a loop, having a valve-controlled opening at one end and a channel forming an extension of the other end of the shaft; a blowing nozzle associated with the outer end of the channel and arranged to blow air outward adjacent such end of the channel so as to draw secondary air outward through the channel and to draw the free end of a thread through the channel and blow it into the shed, the shaft also having a separate lateral aperture between the channel and the valve-controlled opening through which a thread may be drawn into the shaft in the form of a loop by suction applied at the valvecontrolled opening, and through which a freed end of such loop subsequently may be drawn into the channel by operation of the blowing nozzle.

Background of the invention This invention relates to a device for storing a weft to be inserted into a shed, which device is to be used in connection with a loom, said device being provided with a shaft adapted to take up by suction action a measured length of a thread in the shape of a loop, which thread is drawn from a thread package. One end of said shaft is provided with a suction opening to be closed by a valve. The opposite end of said shaft cooperates with a blowing device for introducing the length of the thread as weft from the shaft into the shed.

Such a device is described in United States Patent 3,024,814. In that device the open mouth of the shaft is positioned at a distance from the blowing device. Further a shaft having a blowing device integral with it is described in United States Patent 3,137,322.

As the interior of the shaft described in the latter patent has the shape of a flat cleft, this cleft is provided with widened parts at each side, which widened parts are adapted as a mixing-tube and to receive the blowing nozzles. In the mouth of the shaft two blowing devices are thus arranged, which blowing devices will be alternately operative.

Summary of the invention The object of the invention is to improve such a device for taking up a loop in a thread by suction action and to blow this thread from the shaft in which it was temporarily stored into the shed of a loom.

According to this invention this is attained in that the shaft is provided with a separate opening for sucking in the thread, which opening is positioned between the blowing device and the suction opening which is to be closed by a valve.

Now the measured length of the thread does not pass the blowing device.

Further the shaft can be rigidly fastened and need not be moved to take up' a further part of the thread as described in United States Patent 3,137,322.

Moreover the shaft can now be provided with only one blowing nozzle.

According to the invention a further improvement of the device is attained in that a thread presenting device is situated in front of the entry part of the shaft, which presenting device cooperates with a thread clamp and a movable part of a cutting device which is provided with a second thread clamp, which movable part during its cutting movement intersects the path of the thread between first said thread clamp and the entrance opening of the shaft in such a way that said movable part takes up a part of the thread for its cutting operation and simultaneously clamps that end of the thread which runs in front of that presenting device.

Now it is possible to situate the entrance for the thread laterally of the shaft which entrance cooperates with the presenting device comprising a stem for pushing the thread into the shaft.

According to the invention the stream of air through said entrance to the shaft is at right angles to the direction of the mainstream of air within the shaft.

A further development according to the invention is attained in that the movable part of the cutting device is shaped in such a way that that movable part during a movement in a direction opposite to the cutting movement, will pass the thread between the entrance of the shaft and the first thread clamp; and the presenting device, when operative intersects the plane in which said part of the cutting device moves.

Brief description of the drawings The invention will be described by an embodiment as illustrated in the accompanying drawings in which:

FIG. 1 is a horizontal section of a blowing device and a part of a shaft and a cutting device cooperating with a presenting device positioned laterally of the shaft;

FIG. 2 is a diagrammatic side view of the cutting device and the presenting device and a partial section of an auxiliary shaft along the line 2-2 of FIG. 1;

FIGS. 38 are diagrams showing the blowing device with the shaft according to FIG. 1 and showing the suction steps for presenting a weft;

FIG. 9 is a perspective view of a loom provide-d with a device for storing a length of weft thread and introducing it into the shed; and

FIG. 10 is a fragmentary side elevation of the device shown in FIG. 1.

Description of the preferred embodiment A device according to the invention, which device for weft insertion by jet action, known per se. The jet nozzle comprises a block In having a recess into which is set a nipple 2a. The inner end of the nipple 2a is smaller than the recess in the block 1a, so as to leave an intervening annular space which constitutes an annular nozzle 1 for air under pressure, which nozzle is situated around a supply channel 2 which extends centrally through the nipple 20. When air under pressure is supplied to the space between the block 1a and the nipple 2a, so as to discharge air under pressure through the annular nozzle 1, the resulting aspiration applies suction to the supply channel 2 for drawing in secondary air and for supplying the thread. A mixing tube 3 is positioned in front of the annular nozzle 1 and the channel 2. The channel 2 merges into a widened part 4 which extends through a block 4a that fits around the outer end of the nipple 2a and is situated in front of the mouth of the shaft 5. The shaft 5 is provided with an internal space 6. Air can be sucked through this space.

The jet nozzle and the shaft described above. are adapted to be mounted on a loom. An entrance opening 7 is situated laterally of the part 4. A thread drawn from a thread package is to be inserted through this opening 7 and suction is then applied to the shaft in order to cause the thread to be drawn in the form of a loop into the shaft. The thread 8 drawn from the thread package runs through a thread guide 9 situated near the mouth of an auxiliary shaft 11 The thread is continuously supplied from the thread package by a mechanism hereinafter described, so that the auxiliary shaft 10 is required to take up slack in the thread and to provide a reserve supply of thread so that a length of thread can be drawn rapidly into the shaft 5 during each successive operation of the shaft 5. A thread clamp 11 is situated at that side of the shaft 11 where the thread 8 passes out from said shaft. The thread clamp 11 is shown in detail in FIG. 2

For the sake of clarity, FIG. 1 shows only the portion of the thread 8 which extends through the thread guide 9 to the thread clamp 11, but a more complete showing of the thread 8 appears for example in FIG. 3. The thread 8 in its path through the auxiliary shaft 10 and the main shaft 5 lines substantially in a single horizontal plane. In FIG. 2, which is a vertical section, the thread is not shown, but it is evident that the thread in emerging from the auxiliary shaft 10 must pass above the upper end of the is shown in its open position. When the thread is to be clamped by the thread clamp 11, that clamp which is in the form of a plunger is moved upward as seen in FIG. 2, and the upward movement of the thread clamp 11 engages the thread where it passes above the upper end of the thread clamp and clamps the thread against the upper portion of the auxiliary shaft 16. PEG. 1, which is a horizontal section, shows only the upper end of the thread clamp 11.

The movable part 12 of the cutting device is shown in FIG. 2. The movable part 12 is rotatably mounted upon an eccentric 21 adjacent to the side of the block4a. The eccentric 21 is fixed upon a shaft 21a which rotates the eccentric 21 in order to drive the movable part 12. As the eccentric 21 rotates counterclockwise in FIG. 2, the movable part 12 assumes successively the full line position, the dashed line position, the dash-dot line position and the dotted line position shown in FIG. 2 and then returns to the full line position. During such movement of the movable part 12, the slotted lower end of the movable part 12 is guided by a fixed pin as shown 'in FIG. 2. The drive shaft 21a is mounted in suitable fixed bearings. This movable part comprises a rocker arm 13 which moves in front of the entrance 7 whenever the movable part 12 travels from its dash-dot line position through its dotted line position to its full line position as seen in FIG. 2. At one side the rocker arm 13 is provided with a knife edge 13, which knife edge cooperates with a stationary knife edge 14 formed on the bracket 46. The side of the rocker arm 13 opposite to the knife edge 13 is provided with rounded edges cooperating with a blade spring 15 adapted as a thread ciamp. The movable part of the cutting device is adapted as one part of the thread clamp whereas the blade spring 15 forms the other part of the thread clamp. Within the widened part 4 and within the entrance 7 rectangular grooves 16 are situated in the lower and upper walls, which grooves are arranged for guiding a stem 18 of a thread presenting device. The stem 18 is rectangular, as shown in FIG. 2. FIG. 1, which is a horizontal section, shows only one of the opposed grooves 16 which receive and guide the stem 18. The groove 16 which is shown in FIG. 1 is a rectangular groove formed in the lower wall of the widened part 4 of the supply channel for secondary air. The rectangular groove 16 which is shown in FIG. 1 is of the proper size and shape to guide the lower portion of the stem 18. As indicated in FIG. 1,

thread clamp 11 which in FIG. 2

the portion 4 of the secondary air channelis wide and fiat horizontally, but is narrow vertically so that the rectangular groove 16 shown in FIG. 1 is cut into the lower wall of this secondary air'channel 4. FIG. 10 is a side elevation showing how the rectangular grooves 16 are shaped to receive the end of the rectangular stem 18 which is shown in FIG. 2. FIG. 10 is a side elevation, looking in the opposite direction from FIG. 2, in which the bracket 4b and the cutting device have been omitted for the sake of simplicity. A circular guiding member 7b which is shown in FIG. 1 is also omitted in FIG. 10. FIGS. 1 and 10 show a rounded notch 7a for guiding the thread, which forms part of the entrance opening 7. As shown in FIG. 1, the notch 7a is narrower vertically than the secondary air channel 4 which in turn is narrower vertically than the rectangular notches 16.

The stem 18 runs in a guide 17 and pushes the thread, the leading end of which is clamped between the blade spring 15 and the rocker arm 13 of the cutting device, into the entrance 7 of the shaft 5. The insertion of the thread will be described with reference to the FIGS. 38.

The stem 18 is provided with a notch for the thread which notch is indicated by a dotted line H in FIG. 1.

FIGS. 6, 7 and 8 show the relationship between the rocker arm 13, the entrance opening 7 and the opening at the clamp 11. At the stage shown in FIG. 6, the thread 8 extends through the opening at the clamp 11 to the entrance opening 7, and the rocker arm 13 is in the position shown in dashed lines in FIG. 2 and is passing underneath the thread 8. In FIG. 7 the rocker arm has reached the position shown in dash-dot lines in FIG. 2. In FIG. 8, the rocker arm 13 has passed through the dotted line position shown in FIG. 2 and has reached the full line position shown in FIG. 2, so that the'loop of thread in the shaft 5 has been cut off from the thread supply by the cutting action of the knife edges 13' and 14, and the cut end of the thread supply is clamped between the rocker arm 13 and the blade spring 15. As described above the rocker arm 13 of the cutting device, in moving from the dash-dot line position through the dotted line position to the full line position shown in FIG. 2, takes up the thread and forces the thread to the knife edge 14 and to the blade spring 15. The

picking up of the thread during the cutting movement takes place in a direction from the thread clamp 11 toward the blade spring 15. The thread is thus picked up during the cutting movement of the rocker arm. During movement of the arm 13 in the opposite direction,

in preparation for the cutting stroke, the thread must not be pushed away, because the arm 13 must get behind the thread in order that it may pick up the thread during the cutting stroke. In order to let the arm 13 pass the thread in preparation for the cutting stroke, the driving eccentric 21 causes the arm 13 to travel from the full line position shown in FIG. 2 through the dashed line position to the dashed-dot line position, i.e., the rounded end 20 of the arm 13 first passes below the thread and then it moves upwardly to make its cutting movement, in order to lead the thread to the blade spring The thread clamp 11, is movable by means of a lever 22, which is slightly S-shaped, for a reason which will be described. As shown in FIG. 2, the lever 22 is rotatably mounted upon a pivot 22a that is supported by they lower side of a frame member 22b shown in FIG. 9. One end. of the pivoted lever 22 barsagainst the bottom .of a rounded head 11a that is formed on the. lower end of the thread clamp 11. The other end of the pivoted lever 22 bears against a cam'22c that is fixed upon a. cam shaft 22a. The cam shaft 22a is a conventional timing cam shaft which performs one rotation with each cycle of the blowing device, which cycle consists in the insertion of a hairpin-shaped weft thread into the fabric. During this cycle the thread clamp 11 is in its. upper or clamping position at the stages illustrated in FIGS.

5 and 8, as indicated by the solid dot, and is in its lower or releasing position at the stages illustrated in FIGS. 3, 4, 6 and 7. The stem 18 can be also driven by a lever 23. As shown in FIG. 9, the operation of the lever 23 is similar to the operation of the lever 22. One end of the lever 23 bears upon a cam 23a fixed on the cam shaft 22d, and the other end of the lever 23 has a vertically extending portion the upper end of which is seen in plan View in FIG. 1. The lever 23 also is pivoted beneath the frame member 22b. The cam 23:: actuates the lever 23 once during each cycle, at the stage illustrated in FIG. 4, to insert the stem 18 so as to present a loop of the thread in front of the shaft 5.

In the diagrams according to FIGS. 3-8 the blowing device represented by the mixing tube 3, the shaft 5 and the shaft 10 is generally indicated. The presenting device is represented by the stem 18, and the thread clamp 11 and the thread clamp represented by the blade spring 15 are also diagrammatically indicated. Further the knife edge 14 and the rocker arm 13 are indicated. The position of the last parts differs in FIGS. 3-8.

For clearness sake a fabric is generally indicated in FIG. 3, which fabric consists of the warp threads 24 and the wefts 25a and 25b. The wefts 25a are inserted in the fabric from the left side in this figure by means of a blowing device, which is not shown in the drawing. The wefts 25b are inserted with a similar blowing device as indicated in this figure.

Each weft which is hairpin like in the fabric consist of a part which is first introduced into the shed, called the A-section, and a second part, which after changing of the shed is introduced in this shed, which second part is called B-section.

Each hairpin shaped weft woven into the fabric thus consists of an A-section and of a B-section. The making up of the A-section is indicated in FIGS. 3, 4 and 5. A thread 8 drawn from a thread package is indicated with a dash dotted line, which thread runs in the shape of a loop through the shaft 10. Further this thread 8 runs over the thread clamp 11 to the thread clamp 15. At the stage represented by FIG. 3, the clamp 11 is open as indicated by a circle in FIG. 3, to permit the thread to run freely through the clamp 11. At this stage a loop of the thread also is being drawn by suction into the shaft 10 as indicated in FIG. 3. Thus a part of the thread is stretched in front of the entrance 7 and by means of the stem 18, having its notch 19 just before the thread 8, :this part of the thread is inserted into the entrance 7. This situation is indicated in FIG. 4. During the insertion of the thread, a loop will be formed as the end of the thread is held by the blade spring 15. During this insertion of the thread by means of the stem 18 a suction action occurs in the shaft, because the shaft is connected to a suction device as will be described. Then the stem 18 is retracted from the entrance and a measured length of the thread in the shape of a loop is taken up by the shaft 5. This loop is indicated in FIG. 5. It is possible that during the retraction of the stem 18a part of the thread could be drawn back. In order to avoid this a notch is provided in the upperwall of the interior of the shaft which notch is indicated in FIG. 1 by means of a dash dotted line 26. A cross section of the shaft 10, as indicated in FIG. 2, has the same shape as that of the shaft 5.

When the loop in that shaft 5 reaches its predetermined length the thread is clamped by means of the thread clamp 11, as indicated by a solid dot in FIG. 5. At this moment the rocker arm 13 moves in a direction opposite to the direction of cutting thus towards the thread clamp 11. As a result the end of the thread is free from the clamp 15. At this moment the blowing device 3 becomes operative and the free end of the thread is sucked into the widened part 4, which part merges into the channel 2. The thread is now blown into the shed and this thread forms the A-section of the weft,

which is to be woven into the fabric in a hairpin like shape.

I Now a B-section of the weft 25a is blown into the shed and further, e.g., an A-section of a next weft 25a. After this, a B-section of a weft 25b is to be blown into the shed. This section is an extension of the A-section which has been already inserted into the shed during the steps which have been described with reference to the FIGS. 35. After insertion of the section of FIG. 5 the remaining part of the thread runs from the edge of the fabric through the blowing device 3 and through the entrance 7. This remaining part of the thread is indi-. cated in FIG. 6. The rocker arm 13 of the cutting device now executes its reversal movement and the arm 13 passes below the thread in order to be ready for a next cutting operation. At this stage thread clamp 11 is open as indicated by the circles in FIGS. 6 and 7. The thread runs past the thread clamp 11 to the entrance 7 as a new loop is taken up by the shaft 5. This loop is indicated in FIG. 7. The arm 13 starts its movement for the cutting action from the position which is indicated in FIG. 7. During this movement the thread clamp 11 is closed as indicated by a solid dot in FIG. 8, and the arm 13 pulls a small loop in the thread 8 and a part of this loop comes between a clamp 15 and the knife edge 14. The thread will be cut and the cut end of the B-section which is stored in the shaft 5 will enter the entrance 7 by the suction action of secondary air for the blowing device 3 which is now in operation. The B-section is now blown into the shed and the loop of the thread leaves the shaft 5. In FIG. 8 the cutting of the thread is indicated.

During the stages illustrated in FIGS. 3, 4 and 5, the shaft 21a on which the eccentric 21 is fixed remains stationary While the arm 13 remains stationary in the position shown in FIG. 2. During the stages illustrated in FIGS. 6, 7 and 8, the shaft 21a and the eccentric 21 make one revolution, while the arm 13 makes one reciprocation and returns to its starting position as hereinbefore described. In this way the cutting device 12 is operated once during each cycle to sever from the thread supply the individual weft thread which is inserted into the fabric in the form of a hairpin. The mechanism for thus operating the cutting device 12 once at the end of each cycle forms no part of the present invention, since every automatic loom is provided with a cutting device which is operated at the end of each cycle to sever an individual length of weft thread from the thread supply, in the manner illustrated in US. Patent No. 3,137,322.

After the thread is blown into the shed the cycle for making up a weft is started again, beginning according to FIG. 3.

The present invention resides in the arrangement of the channel 4 and the entrance opening 7 relative to the shaft 5, and in the way in which the thread is introduced through the entrance opening 7. In the practice of the present invention, the loom, the blowing nozzle 1 and the shaft 5 are operated in the conventional manner and a conventional arrangement of valves and controls is employed for supplyig air to the nozzle 1 and applying suction to the shaft 5 at the proper stages.

Air under pressure is admitted to the annular nozzle 1 of the blowing device through the line 27 (FIG. 9).

The blowing device is provided with a valve, located in a valve housing 27a which controls the admission of air under pressure to the line 27 in order to energize the blowing device at the right moment when the reed of the loom is in a retracted position. The stem of this valve can be controlled by means of a lever 29 cooperating with a cam 29a on the cam shaft 22d driven by the main shaft of the loom. The lever 23 cooperates with a cam 23a on the same cam shaft 22d as hereinbefore described.

The shaft 5 also is constructed and operated in the conventional manner, as described in US. Patent No.

3,024,814. FIG. 9 shows how the shaft is mounted on the frame of a conventional type of loom. The body portion of the shaft 5 is arranged in a vertical position toconserve space, and. is secured to the side plate 26 of the frame which is the side plate in which one end of the cam shaft 22d is rotatably mounted. As shown in FIG. 9, the portion of the shaft 5 adjacent the mouth of the shaft, which portion also is shown in FIG. 1, extends horizontally from the vertical body portion of the shaft 5. To connect the shaft 5 to a suction device the shaft 5 is provided with a suction opening 31), which is connected to a suction line 31 a part of which is shown in FIG. 9. The suction line 31 is connected to a suction device through a valve which is located in the valve housing 27a and which can be closed by means of a valve operating lever 32 which is actuated by a cam 33 fixed on the cam shaft 22a. The cams 29a and 33 control the supplying of air under pressure and the application of suction in the manner which is conventional in the operation of air-jet looms, in order to store each leg of an individual weft thread in the shaft and then blow such leg into the shed. One stage at which air under pressure is supplied to the blowing nozzle 1 occurs at the moment when the rocker arm 13 moves to the right from the position shown in FIG. 5, to release the end of the thread from the clamp 15. At this moment the valve through which suction is applied through the line 31 to the shaft 5 is closed, so that the shaft 5 constitutes a dead air space and the entrance opening 7 is the only source through which secondary air can enter the secondary air channel 2. Under these conditions, when air under pressure is supplied to the annular nozzle 1, the jet action of the nozzle 1 indrawing the secondary air through the

channels

2 and 4 creates a powerful suction at the entrance opening 7. Thus, when the rocker arm 13 moves to the right from the position shown in FIG. 5, to release the end of the thread from the clamp 15, the suction created at the entrance opening 7 draws the free end of the thread into the entrance opening 7 and through the

secondary air channels

2 and 4, so that the. free end of the thread enters the jet of air from the annular nozzle 1 and is blown into the shed. At the same time, because of the fact that the shaft 5 is a dead air space, the loop of thread in the shaft 5 remains undisturbed until it is pulled out of the shaft 5 by the movement of the free end of the thread through the secondary air channel 2. Another stage at which air under pressure is supplied to the annular nozzle 1, while the suction is cut off from' the shaft 5, is the stage immediately following that illustrated in FIG. 8. At the stageillustrated in FIG. 8, the rocker arm 13 has just severed from the thread supply the loop of thread which is stored in the shaft 5. Then the powerful suction created at the entrance opening 7 causes the cut end of the loop of thread in the shaft 5 to be drawn through the entrance opening 7 and through the secondary air channel into the jet of air flowing from the annular nozzle 1, to blow the free end of the thread into the shed.

The thread 8 runs from the thread package 35 via the thread guide 36 to the rollers 37. These rollers rotate with a uniform speed. The thread runs further to the auxiliary shaft 10 and the members already described with reference to FIGS. 1 and 2. The arrangement of the device according to the invention in a loom is shown in FIG. 9. In the usual way the loom comprises left and right frame structures 38a and 38b between which the cloth beam 34 is situated. The warp threads 24 run through the shafts 40 and the reed 41,

The blowing device 3a is directed towards the shed. A similar blowing device 312 is also situated in the right frame structure 38b together with the concerning shafts, rollers and thread package in the same manner as is shown in the left frame structure 38a.

I claim:

1. A device for storing a length of weft thread and introducing it into a shed, comprising a shaft adapted to take up by suction a measured length of thread in the form of a loop, and a valve-controlled opening at one end of the shaft, wherein the improvement comprises a channel forming an extension of the other end of the shaft, and a blowing nozzle associated with the outer end of the channel and arranged to blow air outward adjacent such end of the channel, thereby drawing secondary air outward through the channel, to draw a free end of a thread through the channel and blow it into the shed, the shaft having a separate lateral aperture between the channel and the valve-controlled opening, through which a thread may be drawn into the shaft, in the form of a loop, by suction applied at the valve-controlled opening, and through which a freed end of such loop subsequently may be drawn into the channel by operation of the blowing nozzle.

2. A device according to claim 1 wherein the lateral aperture is so directed that the flow of air into such' aperture is at right angles to the main flow of air in the shaft.

3. A device according to claim 1 wherein the interior of the shaft is in the form of a narrow slot, and the width of the channel at its inner end is substantially as great as the transverse length of such slot, but becomes narrower toward the outer end of the channel.

4. A device according to claim 1 comprising an intermittently operated mechanism including (a) a cutter for cutting ofl? and releasing the trailing end of a loop'of thread stored in the shaft, and (b) a clamp for simultaneously clamping the cut end of the thread supply; and an intermittently operated member for presenting, at the lateral aperture of the shaft, a portion of the thread supply adjacent such clamped cut end, to permit a fresh loop to be drawn into the shaft from the thread supply.

5. A device according to claim 4 wherein the member for presenting the thread operates by reciprocating in a direction perpendicular to the direction of movement of the cutter. V 7

References Cited HENRY S. JAUDON, Primary Examiner.