Abstract: A giver rapier head (1) comprises a presentation space (9) between a successive guide nose (11), for leading off warp threads (23) on one side (7), and a selection nose (8), for leading off warp threads (23) on the other side, so that a weft thread (2) can be directly presented in this presentation space (9) and can engage from there in an insertion space (15) between the selection nose (8) and the first-mentioned side (7). A giver rapier (1) has a limit guide arc (10) which is arranged at the front side of the giver rapier (1) and a selection nose (8) which is arranged on the top side, with its top (26) facing the guide arc (10). A rapier weaving machine (20) comprises such a giver rapier head (1). In a method for inserting a weft thread (2), the giver rapier head (1) is moved towards this weft thread (2) while the reed (19) beats up an inserted weft thread (2).
October 24, 2014
Date of Patent:
August 15, 2017
NV MICHEL VAN DE WIELE
Brecht Halsberghe, Vincent Lampaert, Steven Debaes
Abstract: A sputtering apparatus includes a target electrode capable of mounting a target, a first support member which supports the target electrode, a magnet unit which forms a magnetic field on a surface of the target, a second support member which supports the magnet unit, and a force generation portion which is provided between the first support member and the second support member, and generates a second force in a direction opposite to a first force that acts on the second support member by an action of the magnetic field formed between the target and the magnet unit, wherein the second force has a magnitude which increases as the magnet unit comes closer to the target electrode.
Abstract: Device intended for extracting weft threads (T) arranged transversely in a straight grain reinforcing ply (F) comprising a hook capable of gripping a weft thread (T) by performing an alternating movement between a high position and a low position, characterized in that the hook engages with a disengageable anvil capable of moving along the path (XX?) of the hook so that when the device is in operation, the anvil is engaged in contact with the hook during all or part of the descending movement of said hook, forming a clamp capable of holding a section of weft between the hook and the anvil the anvil is disengaged from contact with said hook during the remainder of the travel of the hook, so as to enable the hook to engage a weft thread (T) and to release a section of weft (T).
Abstract: A gripper head of a weaving machine has a clamping device for clamping a band-shaped weft material to be inserted into a loom shed of the weaving machine. The clamping device includes a stationary clamping jaw and a movable clamping jaw that is loaded by a spring and movable about a rotation axis. Each clamping jaw respectively has a clamping surface. The movable clamping jaw is actuatable by a control device to open the clamping device. The gripper head includes a frame, and the clamping surfaces are arranged essentially outside of the frame, but the spring and the rotation axis are arranged inside the frame.
Abstract: The weft-braking device comprises a first annular plate coaxially supported in front of the delivery end of a stationary drum of a yarn feeder, and a second annular plate which is coaxially biased against the first annular plate by driving elements. The yarn is adapted to run between the annular plates in order to receive a braking action by friction. The driving elements comprise at least one piezoelectric actuator, which is deformable in response to a voltage applied thereto and has a movable operative end which is operatively connected to the second annular plate and a stationary operative end which is anchored to a stationary support.
Abstract: The machine (1) for making fabrics comprising yarns decorated with pearls (15) comprises a yarn holder (2) for feeding a warp yarn (3) to a weaving group (5) by aligning all of them onto the same plane by means of cords (7) controlling the feeding direction of the warp (3). The weaving group (5) comprises a reed (9) therethrough the warp yarns (3) pass and cooperating with a bar (11) for forming the fabric (8). The weaving cloth (5) comprises two pincers (13) suitable for inserting a weft yarn between the warp yarns (3). The bar (11) has an indentation (16) faced towards the reed (9) and placed at the passing area of the warp (14). The pincers (13) have a first jaw (18) faced towards a second jaw (19) with substantially triangular profile. The invention also relates to the fabric made with such machine.
Abstract: A system and a method are disclosed for weaving SC fabrics using multiple weft insertion. The system and method may be used to increase the thread count of the SC fabric while reducing fabric costs.
Abstract: A power loom includes a frame, a plurality of warps, a weft spool, a plurality of wefts, and a speed adjustment device. The speed adjustment device includes a support rack, a rotation shaft, a drive motor, a sensor, a press member, and a press rod. Thus, when the output speed of the wefts is gradually reduced to a preset value, the wefts are tensioned and moved upward, and the press member is moved upward to touch the sensor which sends a signal to actuate the drive motor which increases the rotation speed of the rotation shaft and the weft spool to increase the output speed of the wefts largely so that the wefts can be pulled outward from the weft spool quickly to prevent the wefts from being torn or broken due to an excessive pulling force.
Abstract: A woven sailcloth comprising warp yarns and fill yarns and having one or more of (i) a 1% warp of at least about 125 and/or a warp efficiency of at least about 17, (ii) a plain weave in which the ratio of fill yarn count to warp yarn count is about 1.1:1 to about 1.8:1 and the ratio of warp yarn density to fill yarn density is about 1.2:1 to about 1.9:1, and (iii) a weight of at least about 7 and at least one of a 1% warp to 1% fill ratio of at least about 4:1, a 1% fill to 1% bias ratio of less than about 1:1, a 1% warp:1% fill to 1% fill:1% bias ratio of at least about 1:1, a 10 lb. warp to 10 lb. fill ratio of less than about 0.5:1, a 10 lb. fill to 10 lb. bias ratio of at least about 1:1, and a 10 lb. warp:10 lb. fill to 10 lb. fill:10 lb. bias ratio of less than about 0.
December 10, 2008
June 10, 2010
CHALLENGE SAILCLOTH INC.
Terry Lee Cronburg, Robert H. Bainbridge
Abstract: A weaving machine starts-up in slow speed operation during a first weaving cycle following the machine start. To help avoid weft breaks, a method is provided to hold a weft thread inserted into the loom shed during the first weaving cycle. A sensor monitors the weft insertion. The inserted weft thread is held by binding threads at a location downstream from an inlet side of the loom shed, before the weft thread is bound by the warp threads. The binding of the weft thread by the binding threads is carried out dependent on a signal of the sensor.
May 17, 2006
Date of Patent:
January 26, 2010
Lindauer DORNIER Gesellschaft mbH
Valentin Krumm, Wolfgang Metzler, Dieter Teufel
Abstract: A method and a clamping device for clamping a weft thread in a jet weaving machine are proposed. The weft thread wire or strand runs through the beginning section (2.1) and the end section (2.2) of a mixing tube. The two sections between themselves form an engagement opening (8) and are connected with a first holding magnet (11) by a counter support (9). An actuator (6) in the form of an elastomeric bellows, which comprises a chamber (10), is located on the beginning section (2.1) of the mixing tube. The chamber (10) is connected to a valve (16) via a supply line (20) and is acted on variably with compressed air. By deformation of the actuator (6), a clamping element (7) connected thereto carries out a tilting movement between the counter support (9) and a contact stop part (19), which contains a second holding magnet (12). The holding magnets (11, 12) lead to an exact and reliable clamping of the weft thread (3).
Abstract: The weaving machine comprises a pneumatic weft insertion. It is fitted with a weaving reed (12), wherein a guiding device (42) is associated with a guiding channel (40) for a weft thread (10). The guiding channel (10) comprising the weaving reed (12) can be pivoted between an insertion position and a stop position for the weft thread (10). Also, a fixed weft thread insertion device (8), which comprises at least two blast nozzles (22), is associated with the guiding channel (40) in the insertion position. A fixed blade (46) is used to cut the inserted weft thread (10). The blast nozzles (22) are pivotably mounted in the transversal direction (Q) counter to the blade (46) in order to improve the weaving machine and are connected by means of a motor drive device (28) in order to displace the blast nozzles (22) counter to the blade (46).
Abstract: A method for the insertion of a weft thread into a shed of a rapier weaving machine is presented in which the weft thread (3) is taken up by a bringer rapier (10) and fixedly clamped in the same by means of a thread clamp, is inserted into the shed by means of the bringer rapier and is taken up by a taker rapier. In the said method the clamping force of the thread clamp in the bringer rapier is additionally controlled during the weft insertion in such a way that the clamping force (F0) during the take-up of the weft thread and/or during the transfer of the weft thread is reduced relative to the clamping force (F1) in the insertion phase lying therebetween.
October 29, 2007
Date of Patent:
September 8, 2009
Remo D'Incau, Marius Bachofen, Davide Maccabruni
Abstract: A control unit for yarn-braking devices in weft feeders for looms, in which the yarn unwinding from the feeder is pressed between a drum and a braking member connected to two linear actuators controlled by position and provided with position sensors. A position control loop receives a position signal from the sensor and compares it with a reference variable in a subtracter for obtaining a position error. A position compensator receives the position error and outputs a reference current entering a current control loop connected to generate a voltage that supplies the actuator. The compensator incorporates a control transfer function that is variable as a function of an elastic constant of a mass-spring equivalent system, where the mass is the mass of the parts in motion between the braking member and the actuators, and the elastic constant matches with the elastic constant of the elastic elements.
Abstract: A seamless woven customised garment devoid of any stitching, inter-locking or joining the cut pieces by any means using any type of yarn, for men, women and children's wear, including designs, patterns and decorations/accessories is the subject matter of the present invention. Judiciously engaging, disengaging and crossing of one or more warp threads at varied levels weave the seamless garments. The invention also claims a weaving machine adaptable for engaging, disengaging and crossing of warps as per pre-designed patterns. It may be noted that in the present invention the warp threads start at warp beam and also ends at warp beam as against in the conventional weaving process warp thread ends at cloth beam.
Abstract: It is the object of the invention to avoid weaving defects, which due to a starting process of a projectile weaving machine in fabrics, especially such with ground weaves, as a cause of the starting process. The object is achieved according to the invention in that the projectile weaving machine is operated in the slow speed running after each starting process during the first weaving cycle, in that during the slow speed running the weft thread is inserted with a velocity adequate for the prescribed operating rotational speed, and in that the projectile weaving machine is operated with the prescribed operating rotational speed directly after the end of the first weaving cycle.
Abstract: The invention relates to a yarn processing system S with a textile machine T, a carrying device P, comprising a round cross-section or square cross-section clamping profile 1 and at least one yarn feeding device F, fixed to the clamping profile, which yarn feeding device fixation has a cut-out 5 and at least one detachable clamping element 7 for mounting on the clamping profile, wherein the cut-out of the fixation B of the yarn feeding device F is either selectively changeable between a round configuration and a square configuration or is embodied to be suitable for both cross-sections.
June 24, 2005
October 9, 2008
Kurt Arne Gunnar Jacobsson, Per Ohlson, Jonas Frendin, Richard Kaufmann, Peter Kiebler
Abstract: A catching device (1) for holding an inserted weft thread in a rapier weaving machine having at least one rapier (6), which is movable along a rapier track (6a), includes a holding channel (5) which can be mounted in a stationary manner on the rapier weaving machine in order to take up a thread end of the inserted weft thread (9) and to hold it. In addition, the catching device includes a deflection nozzle (3) which can be mounted in stationary manner on the rapier weaving machine in order to deflect the thread end of the inserted weft thread to the holding channel (5).
Abstract: The present invention provides a method for manufacturing a fabric and an apparatus for manufacturing a fabric that enable weaving of weak fibers including monofilaments of noble metal such as 24-carat gold.
Abstract: The method for weaving low flaw cloths (4) comprises an elimination of weft thread sections which have irregularities (22, 22?). The method is carried out by means of a weaving machine (1) which in the presence of an irregularity on a weft thread (2) to be woven can be controlled in such a manner that at least one weft thread section which comprises the irregularity can be removed from the cloth being formed after an insertion operation. The irregularity is in each case detected by a sensor (23a, 23b, 23c) prior to the feeding in of the weft thread into a thread store (21). After the detection of the irregularity an incorporation of the weft thread into the cloth is prevented in that a shed forming apparatus (100), for example a dobby for the moving of heald frames (10), is controlled in such a manner that that all warp threads (3) of the cloth to be formed are deflected either downwardly or upwardly into positions to the side of a weft thread insertion line (2?).
Abstract: The filaments in a weft thread or yarn in a pneumatic loom are tangled and consolidated to prevent untangling of the weft thread when it is transported, after the tangling, through the weft insertion channel in a loom shed. For this purpose the leading end of the weft thread is temporarily stopped in a weft insertion nozzle pipe by a first air stream the so-called holding air stream (19) with a first pressure (P1) between two weaving cycles following each other for holding the weft thread stretched. At the same time a second air stream (20) having a higher pressure (P2) than the first pressure (P1) and a different flow direction than the first air stream (19) is applied to or along a leading end portion of the weft thread for tangling the filaments and thereby locking or consolidating the filaments in the weft thread. Each weft insertion nozzle pipe has a first port and a second port through which the first and second air streams are introduced into the weft insertion the nozzle pipe.
Abstract: The method of disposing the weft, in a loom for displacing the weft led into a weft insert nozzle by jetting the air current from a guide nozzle disposed in a reed sley and releasing the weft from the upstream side of the weft inset nozzle to the vicinity of an intake of an discharge device, is characterized in that, when displacing the weft to the vicinity of the intake, the reed sley is stopped at a position where the air current from the guide nozzle is directed to the vicinity of the intake.
Abstract: A weaving machine, in particular an airjet loom, which is fitted with a system (16) for cutting a filling thread (12?), which is being held ready for filling insertion, from a filling (12) already beaten into a fabric (10), wherein the system (16) includes a laser.
Abstract: A weaving machine, in particular an airjet loom, which is fitted with a system (16) for cutting a filling thread (12′), which is being held ready for filling insertion, from a filling (12) already beaten into a fabric (10), wherein said system (16) includes a laser.
Abstract: An actuator (A) for a component (2), comprising at least one defined stop position, in particular to a brake component actuator of a yarn brake (B), for a selective braking of a running yarn (Y) which actuator has a drive element (D) for linear or rotational adjustment of the component (2). Said actuator is provided with at least one stop device (C). The stop device (C) consists of an additional body (Z), supported in a displaceable manner on a motion damping device (F, G, H). The actuator (A) in the yarn brake is a reversible motor, suitably a magneto-electric motor (M) for rotational movement. An additional body (Z), supported in a displaceable manner on a motion damping device, is provided in each stop device, at which the yarn brake is to stop. During a linear adjustment of the component (2), the mass (m1) of the additional body (Z) matches the mass (m) of the displaced parts.
Abstract: In an arrangement for the linear measurement and magazine storage of thread (7) ahead of the pick in looms or textile machines (18) use is made of thread feed elements (1) and thread length-measuring elements (2) together with magazines (6) designed to store a predetermined length of thread ahead of the pick in the machine. Elements (5, 5′) reversing parts of the thread are designed to bring about interaction with thread parts between the thread support elements. The reversing elements are designed, during said interaction, to displace thread parts in directions that deviate from the feed direction into the magazine or magazines to a position or positions therein. The reversing elements are designed, after the introduction of read parts into the magazines, to return to their starting positions or home positions. The magazines are designed with devices, which retain parts of the thread in said positions.
Abstract: The apparatus (1) for making available a leno thread (2a, 3a) for a weaving machine comprises a shaft (4) which is rotatably journalled about an axis of rotation (A). This apparatus has an active connection to a drive apparatus (5) in order to set the shaft (4) into rotation, and comprises a holder apparatus (6) for accommodating a leno thread bobbin (2, 3), with the holder apparatus (6) being rotatably connected to the shaft (4). There is included a holder means (7) for the substantially rotation-free holding of the holder apparatus (6), and a thread guiding element (8) which is firmly connected to the shaft (4). The holder apparatus (6) is designed for the accommodation of at least two leno thread bobbins (2, 3). The shaft (4) has a thread guiding passage (4a) which opens towards the holder apparatus (6) and which is designed in such a manner that both leno threads (2a, 3a) passing through the thread guiding passage (4a) can be supplied to the thread guiding element (8).
Abstract: A device for the selective braking of a running yarn including a controlled yarn brake having at least two brake elements between which the yarn runs, which brake elements can be elastically pressed against each other with an adjustable force that determines the braking effect. The device also includes a first actuator for the temporary nullification of the braking effect, a control device to which the first actuator is connected, and a device for adjusting the brake force. The adjustment device includes a second actuator, which is also connected to a control device.
Abstract: A fill yarn holding apparatus for use on an air jet loom of the type used for weaving certain fabric patterns where each pattern has at least two fill yarns introduced between each harness reciprocation, and including a pivotal sley shaft, a reed mounted on the sley shaft, at least one air jet for propelling fill yarns across the length of the reed, after which the reed beats the successive fill yarns against the fell line of the fabric being woven, and the harnesses cross to lock in the weave pattern.
Abstract: An apparatus and method for pairing at least two threads for processing in a textile machine. The apparatus includes individual thread feeding devices for furnishing individual threads to a pairing device in which the individual threads are formed into a single resulting paired thread, and a paired thread feeding device, which includes a cylindrical accumulator coaxial with the individual thread feeder devices, for receiving the single resulting paired thread from the paired feed device and delivering the single resulting paired thread, under controlled tension, to the textile machine.
Abstract: At least one of two flexible leaf springs that form a thread gap is controlled by a linearly moveable element of a linear motor or drive. Multi-thread brakes are formed by assembling a plurality of such brakes on a common support whereby a single stator may cooperate with a plurality of linearly moveable armatures forming a corresponding plurality of thread brakes or each thread brake may have its own stator and its own armature arranged in a row either linearly or along a curved support, whereby a compact structure is achieved.
Abstract: A regulator works with a thread or yarn supply which is intended to provide a draw-out length of the thread or the yarn which is dependent on the one hand on the size of the supply and on the other hand on an assumed or adjusted thread tension in the draw-out thread or the draw-out yarn. A load cell is arranged so as to sense the actual thread tension in the drawn-out thread and to, supply to the regulator information for changing the size of the thread stock when the actual thread tension deviates from the assumed or previously adjusted thread tension (the desired value). The load cell can also function as a pick monitor.
Abstract: A method for controlling electrically actuated weft brakes for automatically adjusting mechanical tension of a weft thread in textile machines with mechanical insertion, comprising the steps of: generating and modulating an excitation current of an actuator of an electrically actuated brake. The above step is performed with a device which comprises a control chip which is sensitive both to variations of mechanical tension measured on the left thread and to an actual value (v) of a travel speed of the weft thread during insertion; the control loop is adapted to recondition a reference parameter of the braking action, determined by the control loop on the basis of a reference tension and a measured tension, with a multiplication factor which is represented by a decreasing function [f(v)] of the actual value (v) of the travel speed of the weft thread.
Abstract: A yarn cutting device for mechanical looms, having two mutually movable blades which are arranged on a mounting surface, at least one of the blades being operable by a drive. The drive is constructed as an electrically energized linear motor, whereby a compact flat construction is achieved which has few movable parts.
Abstract: Device for weft cancellation on a weaving machine offers wefts (1), (2), (3) to at least one weft insertion (5), (6), (7) on a weaving machine, which can be operated in order either to bring a weft within the feed area of a weft insertion or to hold it out of this feed area, to effect a weft cancellation. The device has a yarn carrier (19) which can be moved by a weaving machine drive in order to bring a weft (2) within the aforementioned feed area. The device can be operated in order to bring the yarn carrier (19) and a weft (2) into a first and a second mutual position, in which this weft (2) can or cannot be carried along by the yarn carrier (19) within the aforementioned feed area. A first embodiment comprises a movable pusher element (22) that can be operated in order to bring a weft (2) into a first and into a second position in relation to the yarn carrier (19). In a second embodiment the yarn carrier (19) can itself be brought into two different positions.
Abstract: A fabric grounding tape and method of making same is disclosed. In accordance with the method the tape is woven on a needle loom using polyester and stainless steel warp yarns. The yarns are maintained under tension during and after the weaving process and are subjected to a heat setting procedure while still under tension. The resultant tape has the hand or feel of a conventional all polyester tape and a low ohmic resistance, i.e. 10 ohms or less per inch. The tape can sustain a multiplicity of laundering cycles without significant increase of resistivity.
Abstract: A weft brake for weaving looms, comprising a rigid, fixed and flat plate made of non-magnetic material and a flexible lamina made of magnetic material, between which a weft thread slides; the flexible lamina is actuated magnetically against the rigid and fixed plate by the action of a plurality of permanent magnets which are supported by a movable yoke; the yoke is subjected to an electric actuator which moves the yoke with respect to the lamina, moving the magnets towards or away from the lamina; due to this action, the attraction applied by the magnets to the lamina varies and accordingly varies the pressure that the lamina applies to the thread.
September 25, 2000
Date of Patent:
September 11, 2001
L.G.L. Electronics S.p.A.
Pietro Zenoni, Giovanni Pedrini, Rosario Castelli
Abstract: A tensioner for gripping an inserted thread in a weaving shed and applying or removing tension based on the thread's inserted tension. Through the use of sensors in a thread gripper, the inserted thread tension is compared to a desired value in a controller which controls the direction of rotation of a drive motor connected to the tensioner. A thread positioner which cooperates with the gripper assures that the threads are repeatedly gripped at the same general location. This expedites the detection of the inserted tension and avoids false initial tension readings.
Abstract: An improved assembly for alternating twist in yarn, utilizing a pair of air jets in which compressed air is supplied producing a vortex that causes the yarn passing therethrough to experience a torque about the yarn's longitudinal axis. This apparatus is used to provide an alternating twist to fill yarn as the yarn is being fed into the loom. The twisting unit operates by imparting “s” twist for a certain period of time while the yarn is in linear motion, followed by imparting a “z” twist for another certain period of time, in repeating fashion. The net twist in the yarn so treated is zero. Preferably, the twisting of the fill yarn is coordinated with the loom so that the twist direction is reversed prior to each successive filling insertion.
Abstract: An apparatus for the insertion of weft threads contains a stationary unit having an arrangement with a plurality of passages, a plurality of nozzles for the supplying of weft threads and a unit which rotates with the weaving rotor with a plurality of injector nozzles which are intended to successively draw off the weft threads which are supplied to the passages and to feed them into the shed.
Abstract: An apparatus for severing a weft thread which is to be inserted into a shed comprises a clamping device with a stationary clamping part and a settable clamping part in order to hold back the weft thread and a severing device in order to sever the weft thread after release by the clamping device. The severing of different yarn types is ensured by means of a problem-free clamping of the weft thread in the thread clamp.
Abstract: A thread clamping device, particularly for the figuring weft threads on jacquard machines, in which figuring weft threads, e.g. those on jacquard looms, are only picked from time to time corresponding to the figured form of the woven jacquard fabric, with the figuring weft threads being held under tension and released as required, during their stationary period, by thread clamping devices which are controlled via the harness thread of the associated figuring weft cord heald.
Abstract: During weft yarn insertion in a loom, as the end of weft yarn insertion approaches, a controllable yarn deviation brake (B), positioned between a weft feeder (M) and a warp shed (F) of a loom (D) brakes the weft yarn (Y) with a high braking force, causing a deviation of the yarn deviation brake which subsequently smooths down a tension peak of the yarn, so as to partially reduce the yarn brake deviation back towards the starting position, or position having no deviation. The same function is performed upon cutting of the weft yarn (Y). After braking and reduction of the yarn tension peak, during the weft insertion step, the braking force is reduced to a level correlated to the yarn tension which prevails up to cutting of the weft yarn (Y).
Abstract: A weft yarn feeding device includes a feed roller which rotates at a circumferential speed equal to a running speed of a weft and a pinch roller which moves in and out of contact with the circumference of the feed roller with the weft in between. The rollers are provided between a length measuring device and a main nozzle for injecting a fluid. Upon commencement of feeding of the weft, the feed roller and the pinch roller are brought into mutual pressure contact to positively feed the weft toward the main nozzle. Further, the feed roller surface has a large frictional coefficient and the pinch roller surface has a very small frictional coefficient.
Abstract: A transport roller (10) is provided on a ribbon loom and a press roller (12) is forced against said transport roller to grip a bobbin supply thread (26). In order to simplify adjustment of the transport speed while keeping the speed of the transport roller constant, a friction surface (32) is provided on the outside of the transport rollers casing or jacket (78) and can be expanded radially by an adjustment device (66, 72).
Abstract: Filament threads such as rayon threads which may be smooth or partly texturized for protection, are texturized or entangled in the loom just prior to their insertion into a loom shed as weft threads. For this purpose a texturizer (4) is positioned between a filament thread supply spool (1) and a weft thread accumulator (3). The accumulator in turn is positioned just upstream of an air insertion nozzle (11) for injecting the weft threads into a loom shed. The texturizing is sufficient to lock the filaments into the filament thread body so that these texturized filaments form threads that can be pneumatically transported through the loom shed without causing so-called blow-outs of individual filaments out of the weft thread body.
Abstract: Weft thread distributor apparatus for a series shed weaving machine in which a weft thread is fed into a connection channel via a supply nozzle and is distributed within the connection channel to shoot-in tubes. In order to achieve a trouble-free cutting off of the inserted weft and rerouting of the new weft thread tip a cutting device is placed spatially between the shoot-in tube and the clamping device in order that a retraction force and a loop standing under said retraction force are already formed due to of the supply nozzle and the injector nozzle prior to the stopping of the weft thread in the clamping device. During the stopping in the clamping device the thread is pre-tensioned in the cutting device and can be cut without difficulty. The loop unwraps itself and a new weft thread tip is inserted into the shoot-in tube.
Abstract: A ribbon loom for making a material web at high speed operates through precise control of the weft thread. The ribbon loom comprises a weft insertion needle to insert a loop of weft thread into a shed. The weft thread loop is tied off by a knitting needle on the side of the web away from the insertion needle. The insertion needle is served by a feed device for the weft thread containing a pneumatically operated compensator in the form of a blower and/or a suction device. The insertion needle also has a separate guide eye for the weft thread. This thus provides a particularly effective compensator ensuring precise control of the weft thread when the ribbon loom is running at high speed. The web edges are always tensioned to the set width and maintained at a constant width.
Abstract: The tension of a weft thread in a loom is controlled during particular time phases within the weft supply, weft presentation, weft seizing, and insertion, including the initial phase of entering into the loom shed. Additionally, the weft thread tension may be controlled during the duration of the actual insertion phase when the weft thread travels through the shed. For this purpose a twin nozzle or two separate nozzles are arranged downstream of the weft supply and preferably upstream of a weft brake or weft stop motion. The double nozzle can supply pneumatic impulses in the insertion direction (ID) and/or in the opposite direction (OD). The operation of the double nozzle is controlled by a program that determines the timing and the duration of the pneumatic impulses applied to the weft thread in the insertion direction and/or in the opposite direction.
Abstract: A weft feeding device which alleviates an excessive tension acting on the weft upon feeding of the weft and inhibits breakage of the weft includes a gripper to grip the weft at prescribed times, a length measuring roller located downstream of the gripper, and a pinch roller to hold the weft against the roller at prescribed times. Opening and closing of the gripper is linked with movement of the pinch roller into and out of contact with the length measuring roller. A linear or a rotary solenoid is provided to operate the pinch roller and the gripper by a pulse width modulation method or a linear method.