Lindauer Dornier Gesellschaft Mbh

Lindauer Dornier Gmbh

Herbert Mueller

Adnan Wahhoud

Thomas Laukamp

Peter Czura

Valentin Krumm

Peter D Dornier

Dirk Janicijevic

Ewald Zimmermann

Michael Langer

Johannes Louven

Horst Haeussler

Dieter Teufel

Peter Schiller

Fritz Gehring

Stephan Arndt

Fritz Rupflin

Siegbert Gsell

Nicolas Mega

Christian Hannes

Hubert Ortmann

Kurt Motz

Stefan Arndt

Arno Wagner

Martin Eberle

Leonhard Groeger

Apparatus for the intermediate storage of two band-like weft materials () for a weaving machine (), with two storage containers () in which respectively a U-shaped loop () of a weft material () can be formed. Machine elements () for the application of tensile forces () onto the weft material () in the inner space () of the respective storage container () are present. The inner spaces () of the two storage containers () respectively orient one of their two narrow sides () toward one another. Deflection elements () are respectively arranged on the storage container () in such a manner so that the respective weft material () can be supplied to the inner space () in a region () that lies closer to that one of the two narrow sides () of this inner space (), which is not oriented toward the inner space () of the respective other storage container ().

Device for the intermediate storage of band-like weft material for a weaving machine and weaving machine having such a device

A weaving machine for producing a woven fabric has a shedding device to form a loom shed of warp material, a weft insertion device for inserting a preferably tape-shaped or band-shaped weft material into the loom shed, a drawing-off device for drawing off the finished fabric in a drawing-off direction, fabric movement device for moving the fabric back and forth in the warp direction to bring the last inserted weft material into contact with the binding point or fabric edge. A shed limiter device limits the opening of the loom shed from above and below the warp, and is movable back and forth in the warp direction. The shed limiter device only loosely bounds the fabric and essentially without actively clamping or pinching or contacting the fabric and/or the last inserted weft material, at least while moving in the direction opposite the drawing-off direction.

Weaving machine having movable shed opening limiter device

For weaving pattern formation of a woven fabric with weft threads (), warp threads () and effect threads (), data sets () are produced according to a method in which data values are derived from weft sequence numbers () and from positions of interlacing points (P) of an effect thread () with the weft threads () in the pattern repeat (). These data sets () are supplemented by further data values () derived from the weaving pattern, in such a manner so that they form a pattern draft () for a weaving pattern with additional weft effects. In a weaving machine with devices for slidingly displacing effect threads () in the weft direction (), the weaving pattern formation is derived from the data sets () of this pattern draft ().

Method and apparatus for weaving pattern formation in woven fabrics with additional weft effects

For transferring a preferably band-shaped weft material from a feed unit to an insertion element of a weaving machine, a free end of the weft material is clamped in a clamping device, the free end is transferred to the insertion element, and then the clamping device is opened to release the weft material, which is then inserted by the insertion element. The clamping device is conveyed by a drive essentially in the direction of motion of the insertion element between at least two different operating positions.

Device for transferring a band-shaped weft material

Ground warp and pile warp thread sheets are supplied to a shed forming device. The ground warp and the pile warp are separately deflected over a deflecting rod upstream from the shed forming device. The deflecting rod supports the ground warp and directs the pile warp to cross and interpenetrate through the ground warp before deflecting the pile warp into the back shed. The deflecting rod is positively driven and controlled to pivot about a horizontal axis to provide a positive controlled partial compensation of the pile warp thread length variations. The pile warp also runs over a pile warp thread reserve and compensating device upstream from the thread crossing location to provide an additional passive uncontrolled compensation of the pile warp thread length variations and to provide a pile warp thread reserve during the pile loop formation and/or the shed changes in the weaving process.

Terry loom with pile warp length compensation and deflection into back shed

A ground warp thread sheet and a pile warp thread sheet are supplied to a shed forming device. Two stop motions on separate planes respectively monitor the pile warp and the ground warp. The ground warp and the pile warp are deflected over a deflecting rod upstream from the shed forming device. The deflecting rod supports the ground warp and directs the pile warp to cross and interpenetrate through the ground warp before being deflected into the back shed. The vertices of the ground warp and pile warp back sheds are thus located on opposite sides of the deflecting rod. The pile warp crosses through the ground warp directly upstream from the deflecting rod, at a steep angle, for example from 45 to 135 &deg;.

Terry loom with interpenetrating ground warp and pile warp

A main drive shaft of a power loom reaches the rated operating rpm of the loom by the time of the first beat-up of the reed, thus avoiding start-up faults in the fabric. A flywheel mass is accelerated to a start-up rpm that is higher than the rated operating rpm before it is coupled with the main drive shaft. The start-up rpm is determined automatically and iteratively, with ever-increasing accuracy in successive starts of the loom. When the main drive shaft is coupled to the flywheel mass, the flywheel mass rpm decreases simultaneously as the main drive shaft rpm increases from standstill to the operating rpm. The actual main drive shaft rpm is measured at least at the time of the first beat-up and any deviation from the rated operating rpm is evaluated by the loom control. After each start-up, a new data set is generated based on the measured values and is used to calculate an updated or modified flywheel start-up rpm in the next start-up operation so that the main drive shaft more accurately reaches at least the rated operating rpm by the time of the first beat-up of the reed.

Method for starting a power loom

A fluid jet loom includes a source of pressurized fluid, a magnetic valve, and at least one nozzle, such as a weft insertion air jet nozzle, as well as at least one flexible pressure hose connecting and providing pressurized fluid from the magnetic valve to the nozzle. In order to detect any hole, rupture or separation of the pressure hose, the hose includes at least one electrical conductor embedded in or arranged on the hose wall. An electrical current flows through the electrical conductor, which preferably forms a conductor loop and especially a resonant circuit loop. By monitoring an electrical characteristic, such as the resonant frequency, of the electrical signal received from the conductor loop, any disruption in the pressure hose can be immediately detected as a change in the monitored electrical characteristic, which in turn causes a loom stop signal to be generated.

Arrangement for monitoring functionality of flexible pressure hoses in a loom

The starting time of a weft thread insertion in a jet loom is automatically adapted to a change in the speed of the main loom drive shaft, in order to assure that the leading end of the weft thread always arrives at the same time at a weft stop motion device at an exit end of a weft insertion channel through the loom shed. For this purpose, the starting time of the weft insertion is advanced when the loom drive shaft rpm is increased and delayed when the rpm is decreased. The advance or delay has reference to a weaving cycle that begins with the opening of a shed and ends when the shed is fully closed. The flight time .DELTA.t.sub.F of a weft thread through the shed is constant. The adaptation is performed in response to measuring the rotational drive shaft angle .alpha..sub.AR at which a weft thread arrives at the weft stop motion device and determining the starting time in such a way that the weft arrival time (t.sub.2, t.sub.4, t.sub.6) always takes place at substantially the same rotational drive shaft angle .alpha..sub.AR.

Method and apparatus for determining the starting time of the weft

Method and device for regulating a back rest and/or a drop wire position

A controlled weft thread presenting and clamping arrangement minimizes weft thread waste and ensures proper tensioning of the weft thread during its presentation to the insertion gripper, in a gripper loom for weaving with plural different weft threads. The arrangement includes a control shaft (13) that has a drive key (14) protruding therefrom in a reference plane (7), and that is rotatably supported on a support bracket (10, 11, 12), which may be mounted on the loom. Weft thread presenting levers (15) each carrying a respective clamp (16) are movably arranged on the shaft (13), which passes through a hole in each of the presenting levers (15). A translational drive (22) acts on a presenting lever support (17) to translationally move all of the presenting levers (15) in unison together axially along the shaft (13) until a selected lever (15) is positioned in the reference plane (7), with the lever's drive groove 15B engaged on the drive key (14) of the shaft (13). A rotational drive (23) rotates the shaft (13), and therewith the selected thread presenting lever (15) via the drive key (14). A guide member (19) has a lengthwise groove (20) to allow all of the presenting levers (15) to move linearly therealong in unison, and a crosswise groove (21) in the reference plane (7) to allow only the selected presenting lever (15) to rotate in the reference plane. A thread back tensioning device (9) is arranged in the thread path to apply tension to the thread being presented to the gripper.

Axially slidable weft thread presenting levers and clamping arrangement

In the event of an interruption of the weaving process and in the case of weaving-technical operations, such as tabby weaving and unraveling, a trailing of warp thread bobbins and thus a trailing of warp threads which are withdrawn from the bobbins and form a warp thread family, cannot be avoided without significant expenditures. The trailing results in a so-called trailing length in the thread family which, unless it is correspondingly taken up and correspondingly released during the new start of the weaving process, results in an overstretching of the warp thread family during a starting operation of the bobbins. This disadvantage is avoided by deflecting the thread family within a feeding stand, in the event of a weaving stop, in a controlled manner from a reference plane into at least one defined position. At the new start of the weaving process, the deflection is eliminated in a controlled manner.

Controlled warp tensioning during fabric weaving

Avivage deposits on and between the dents of a reed, especially in an air weaving loom, are removed by heating at least a portion of the reed dents in the vicinity of the weft insertion channel to a temperature sufficient to melt the avivage which can then be discharged from the reed dents and the spaces between the reed dents by dripping downwardly, for example, into a collecting trough.

Method and apparatus for cleaning the dents of a weaving reed

When a faulty weft thread must be removed after it has been bound into the fabric and beat-up, it is necessary to perform a so-called reverse weaving operation following the stopping of the normal weaving operation in response to a stop signal signifying that a faulty weft thread has been detected. For this purpose the loom main shaft and the heald drive shaft are rotated for a number of rotational degrees in the same direction in which these shafts are rotated just prior to the stopping of a weaving operation in response to the above mentioned signal. Next, the drive between the main shaft and the heald shaft is interrupted. Next, the main shaft and thus also the reed shaft and with it the reed, are rotated back within a predetermined angular range between two successive reed beat-up motions. During this time the heald shaft is rotated back, preferably to the so-called detection point with a higher r.p.m., or rather with a higher angular speed than the main shaft. This function is accomplished by an auxiliary step-up transmission gear between the main shaft and the heald shaft. The auxiliary gear is bypassed during normal operation when there is no weft fault and it is connected in series during the operation for removing of a faulty weft thread.

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Kressbronn, Germany

Herbert Mueller