Image analysis – Applications – Textiles or clothing
Reexamination Certificate
1999-08-09
2003-06-17
Mehta, Bhavesh M. (Department: 2625)
Image analysis
Applications
Textiles or clothing
C250S559400, C242S118000, C356S238200
Reexamination Certificate
active
06580813
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a method and a corresponding apparatus for detecting residual yarn remaining on spinning cop tubes, for use in automatic bobbin winding machines.
Modern spinning machines have a high output of spinning cops, and so more stringent demands are made of the processing capacity of the spinning machines downstream as well.
It is also necessary for the unwound tubes to be returned in adequate quantity to the spinning machine. To assure a high degree of automation, closed transport loops in the region of the spinning machine and optionally direct coupling of automatic bobbin winding machines to the spinning machines are therefore widely used.
In modern automated textile production facilities, the spinning cop tubes are thus subject to a circulatory process. The flow of material in such a closed spinning cop and tube transport system in the prior art, as known for instance from European Patent Disclosure EP 0 402 731 B1, is shown schematically in FIG.
6
. Once the yarn has been made in a ring spinning machine, the resultant spinning cop is automatically delivered to the bobbin winding machine, where the cop is mounted on a cop carrier. Via conveyor belts, the spinning cop is transported from the mounting station to a cop preparation station
4
, so that the end of the yarn can be separated thereby and made ready for being securely grasped later. The spinning cop then moves into a winding station
1
, where the winding process is performed.
However, it can happen that the bobbin winder loses the beginning end of the yarn on the spinning cop in place, especially if the yarn breaks. After a few failed attempts at splicing, the spinning cop tube is treated as being presumably empty and is finally ejected from the spinning station
1
. Thus, it is not assured that the ejected spinning cop tubes are in fact always empty. On the contrary, the ejected spinning cop tubes differ in terms of how much yarn remains on them and accordingly their reprocessing must be different.
To automate the winding process, it is therefore necessary to determine the status of the spinning cops shunted out of the winding station
1
, so that individual residual yarn windings remaining on the cop tube or a possibly full or otherwise usable amount of residual yarn remaining on the spinning cop tube can be detected reliably. To that end, in the transport system shown in
FIG. 6
, an electromechanical tube monitor
2
is provided, which detects the amount of residual yarn remaining on the spinning cop tube.
The tube monitor
2
can be designed in the form of an electromechanical sensor (see for instance German Patent Application DE 41 10 626 A1), in which a metal comb sweeps laterally over the spinning cop tube. Depending on how far this comb can sweep over the tube, conclusions can be drawn as to the remaining quantity of yarn on the spinning cop tube. Spinning cops that have been completely unwound, i.e., empty tubes, are automatically transported back to the spinning machine to be refilled. Conversely, if a residual yarn remaining on the spinning cop tube has been detected by the tube monitor
2
, then for instance with the aid of shunts the transport direction of the applicable spinning cop tube is diverted such that the spinning cop tube is delivered over a secondary route to a tube cleaning device
3
. This tube cleaning device
3
has the task of removing the remaining yarn from the spinning cop tube. To that end, the yarn package is optionally cut open and then stripped off the spinning cop.
However, since it can also happen that the residual yarn remaining on the tube can still be reused and thus can be delivered to the spinning station
1
again, the tube monitor
2
also provides a statement as to whether the remaining yarn quantity detected on the spinning cop tube is sufficient to be reused. If so, then the spinning cop tube is not delivered to the tube cleaner
3
but rather is transported to the cop preparation unit
4
, which in turn grasps the beginning of the yarn on the spinning cop and after placing this beginning end of the yarn at a predetermined point delivers the spinning cop to a winding station
1
.
Instead of the design shown in
FIG. 6
, in which the tube monitor
2
serves as a multifunction sensor that can distinguish between empty tubes, tubes with a slight residual yarn, and tubes with a still usable residual yarn, it is also possible at the position of the tube monitor
2
to provide a first sensor, which detects merely whether a residual yarn is or is not present on the spinning cop tube. In that case, before a branching point toward the tube. cleaner
3
, a further sensor is provided, which finally distinguishes whether or not the remaining residual yarn is sufficient for reuse and, by suitably controlling the transport route as a function of this decision, delivers the spinning cop tube either to the cop preparation station
4
or the tube cleaner
3
.
As already explained above, in the bobbin winder shown in
FIG. 6
an electromechanical spinning cop feeler in the form of a metal comb may be used as the tube monitor
2
, but this has multiple disadvantages. For instance, in this design, the tube monitor
2
must be readjusted by hand for different types and sizes of spinning cop tubes. The metal comb can also wear down over time, and individual remaining yarns are not removed from the spinning cop tube but are instead merely pushed downward by the metal comb, so that these remaining yarns become tangled with the new yarn in an ensuing spinning process and thus can cause the ring spinning spindle to stop. It is also disadvantageous that the mechanical feeler elements of the sensor can damage the yarn, particularly fine yarns.
Japanese Patent Disclosure JP 63-107370 describes a similar mechanical sensor for detecting remaining yarns on spinning cop tubes. According to this reference, a rotatably supported mechanical arm is moved from top to bottom along the spinning cop tube and, depending on the degree to which the spinning cop tube is filled with yarn, the rotatably supported arm can be deflected to a variable extent. The deflection of the arm is detected with the aid of a suitable sensor, in order to draw conclusions as to any possible remaining yarn windings on the spinning cop tube.
In addition to the above-described detection of residual yarns on spinning cop tubes with the aid of mechanical sensors or feelers, devices are also known that detect remaining yarn or residual yarns on spinning cop tubes in contactless fashion.
To this end, German published examined Patent Application DE-AS 1 278 308 proposes irradiating the spinning cop tube with the aid of a light source such that the light reflected by the spinning cop tube may be detected with the aid of a photocell. The beam of light reflected from the spinning cop tube affects the photocell more or less, depending on whether a winding residue is or is not present on the spinning cop tube. During the scanning operation, a relative motion always occurs between the spinning cop tube and the photocell acting as a sensor, i.e., the spinning cop tube is moved horizontally past the photocell.
It is furthermore known from German Patent DE 40 08 795 C2, which defines the generic starting point for the present invention, to detect residual yarn remaining on a spinning cop tube by scanning the spinning cop tube with the aid of a relative motion between the spinning cop tube and a sensor, while the spinning cop tube is being transported in an upright disposition; the sensor is mounted on a stationary lifting divide, with the aid of which it is moved along the spinning cop tube with an approximately constant spacing from the surface of the tube. In particular, the sensor may be a photosensor, which evaluates light shone at a certain angle from the vertical onto the surface of the spinning cop tube and reflected back by the spinning cop tube, so as to detect residual yarns on the spinning cop tube.
Finally, Japanese Patent Disclosure JP 54-30943 also teaches contactless bobbin sc
Hermanns Ferdinand-Josef
Krüger Andreas
Müllers Harald
Kennedy Covington Lobdell & Hickman LLP
Mehta Bhavesh M.
Tabatabai Abolfazl
W. Schlafhorst AG & Co.
LandOfFree
Method and apparatus for detecting residual yarn on spinning... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for detecting residual yarn on spinning..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for detecting residual yarn on spinning... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3119424