Typical to other weft detection systems, the sensitivity and control zone have to be defined. With the Maestro System, the control zone is defined specifying the degree in the weaving cycle for the start and stop of the 2 zones in which the weft insertion is controlled. The first zone goes from the beginning to the middle of the insertion; the second zone from the middle to the end. In each of the 2 control zones, the software will check if the numerical value of the inserted weft is above the threshold. The thresholds are predetermined and defined for each eyelet. This is an easy procedure by using the up/down arrows on the touch screen display. Therefore, the need to use potentiometers or other setting methods is eliminated.

The individual sensitivity setting or definition of the threshold does not make the Maestro more expensive, all functionalities are handled through software. During weaving Maestro will continuously compare if the numerical values transmitted by the weft detector stays, while in a control zone, above the defined threshold. If not, Maestro will stop the loom for weft breakage.  

Another feature of the new Maestro System allows the weft pattern information to be linked with the signal processing of the numerical values provided by the weft detector. This is completely automatic, requiring no technician intervention. What does this mean?  

• If the weft of one eyelet position has to be inserted and for some reason another weft is inserted, Maestro will detect this and stop the loom.
• If two wefts are to be inserted and for some reason only one or three wefts are inserted, Maestro detects this and the loom will be stopped.
• If two wefts are to be inserted and for some reason one of the two wefts is the wrong one, Maestro will detect this and stop the loom.

Because of this functionality any malfunction of the weft selector or any case where a weft yarn gets entangled with a neighboring weft, Maestro will stop the rapier loom. Clearly Maestro is a further step in the direction of a rapier weaving machine which guarantees perfect fabric quality.

Some further words concerning the definition of the thresholds, which can be set individually for each eyelet. For a fine weft yarn count, the numerical value will be lower than for a course yarn. If the technician wants to weave with minimum weft yarn deflection (weft yarn as much as possible in a straight line) the numerical values produced by the weft detector will be lower. Maestro visualizes these values and illustrates the weft insertion curve on the loom’s display. The technician can easily define the individual threshold for each weft yarn in such a way that every weft break will be detected without creating false or unwanted weft stops. The insertion curves also allow the technician to have a clear view of the signals received at the end of the weft insertion. This allows him to weave with the longest weft control zone. What is meant here is that the yarn will be monitored to the point the weft is released from the gripper. This feature certainly serves to eliminate defects for short picks while also preventing false stops. Further, a more controlled and precise release from the gripper is assured. Consequently, the Maestro System also reduces weft yarn waste.

 With Maestro, ITEMA introduces a new look at weft monitoring and the detection of weft breakages on rapier looms. Thus, the complexity for the technician is removed and handled by the software operating with the micro-processor of the weaving machine.

 Without adding cost to the weaving machine, the Silver 501 rapier loom assures better quality with Maestro in charge of weft detection.