Thread end searching arrangement

A thread end seeking arrangement for preparing a predetermined length of thread for insertion into a core of a cop carrying the thread. The arrangement includes a streaming channel located at a seeking/detection point for coupling to the cop and receiving the thread from the circumference of the cop. A thread engager is provided at the streaming channel and is spaced from one end of the streaming channel by a distance corresponding to the predetermined length of the thread to be inserted. The thread engager is operable to engage the thread at the end of the predetermined length of the thread.

BACKGROUND OF THE INVENTION 
The invention is directed to a thread end seeking arrangement employing a 
cop holding arrangement which is rotatable about a vertical axis and 
employing a streaming channel for the reception of the thread end wound 
circumferentially around the cop. 
A thread arrangement of this type is a preparation stage for a spooling 
machine or the like. This arrangement receives spin cops either directly 
or indirectly from the spinning machine or alternatively, cops which are 
returned thereto by reason of their rejection from the spooling machine. 
The thread end is sought, a predetermined length is pulled off and 
thereafter attached to the cop in a predetermined manner, either by the 
formation of a plurality of external circumferential loops or, by 
insertion into the cop core. The thread end prepared in such a way can be 
readily grasped in the spooling machine and knotted or spliced with the 
thread end in the winding spool. 
In the known arrangement (DEOS No. 3630836), the cop holding arrangement 
carrying the cop, is transported to such a seeking station on a 
predetermined pathway. At this point, the suction slit of a suction pipe 
is provided proximate to the rotating outer surface of the cop. The thread 
end is grasped by the suction stream and pulled into the suction pipe. 
Then the cop holding arrangement is moved onto a cutting position. There 
is then provided above the cop, a combined thread testing and cutting 
arrangement. The suction pipe bent over the cutting point longitudinal 
slit so that the portion of thread taken up in the suction pipe can follow 
the movement of the cop. 
If the testing arrangement determines that no thread end has been taken up, 
the cop is shifted to a side path and brought back to the seeking point by 
activation of a touching arrangement on the upper surface of the cop. An 
improved result is alleged to be obtained by the seeking arrangement. 
An object of the invention is to provide a thread seeking arrangement of 
the foregoing type in which the number of process steps through which the 
cop has to pass is reduced. 
SUMMARY OF THE INVENTION 
In accordance with the illustrative embodiments demonstrating features and 
advantages of the present invention, there is provided a thread end 
seeking arrangement for preparing a predetermined length of thread for 
insertion into a core of a cop carrying the thread. The arrangement 
includes a streaming channel located at a seeking/detection point for 
coupling to the cop and receiving the thread from the circumference of the 
cop. A thread engaging means is provided at the streaming channel and is 
spaced from one end of the streaming channel by a distance corresponding 
to the predetermined length of the thread to be inserted. The thread 
engaging means is operable to engage the thread at the end of the 
predetermined length of the thread. 
By employing such apparatus, improved testing and/or cutting arrangements 
are provided in the streaming channel at a distance from the seeking point 
corresponding to the desired length of the thread end. In this 
arrangement, there is no requirement for a remote testing be tested and 
its separation achieved while the cop is still in the seeking position. 
This leads to a considerable saving in space. 
There is a further advantage because the streaming channel has 
substantially closed walls. Because of the provision of the testing and/or 
cutting arrangement in the streaming canal, the latter requires no 
longitudinal slit for the movement therethrough of the thread ends. Thus, 
it is possible to drive the suction arrangement connected to the streaming 
channel with a considerably lower consumption of energy or alternatively, 
a much higher streaming velocity may be utilized, which in turn increases 
the success rate of the search step. 
In a further embodiment, the streaming channel is connected with a suction 
arrangement and on one side of the cross-section of the streaming channel, 
there is provided an air cut-off slider which can be moved across the said 
cross-section by means of a servo motor. By means of this air cut-off 
slider, the action of the suction arrangement is terminated and the thread 
end can be manipulated without the further influence of suction.

DETAILED DESCRIPTION OF THE DRAWINGS 
Referring to FIGS. 1 and 2, there is provided into streaming channel 1 
which possesses a substantially closed tubular wall, a combined testing, 
cutting and blocking arrangement 2. This arrangement is activated by an 
axial servo motor 3 whose pressure volumes on both sides of piston 4 can 
be supplied with pressurized air via magnetic valve 5, either over 
connection 6 or connection 7. The appropriate piston rod 8 carries an a 
U-shaped outer bracket 9 and a U-shaped inner bracket 12 telescopically 
connected thereto via spring 10 and contact head 11, which may be moved 
from the position shown in FIG. 1 to the position shown in FIG. 2 and vice 
versa. 
a. Thread Testing Arrangement-- on one side of cross-section 13 of 
streaming channel is provided an inlay 14 having two clamping surfaces 15 
and 16. These work together with the arms of bracket 12 in order to hold 
fast thread segment 17. Between the two clamping surfaces 15 and 16, there 
is provided a probe 18 which is connected to a piston 19. This piston 19 
is biased on one side by spring 20 and, by means of air pressure provided 
through inlet connection 21 during the backwards movement of piston rod 8 
to stepped space 22, to the illustrated end position. The actual position 
of piston 19 is monitored by sensor 23 to provide a proximity sensor. 
Where the probe 18, illustrated in FIG. 1, is held in place by the thread 
segment, sensor 23 does not communicate. On the other hand, if thread 
segment 17 fails, the piston 19 moves further to the right so that sensor 
23 gives an altered signal. Sensor 23 is connected with a control 
arrangement S which (by means of signals communicated to conveyor 40 of 
FIG. 3), ensures that at failure of the thread, the cop remains in the 
seeking position and a new seeking process is begun. 
b. Thread Cutting Arrangement-- In a similar manner, it is advantageous to 
provide a counter surface 25 on one side of the cross-section of the 
streaming channel 1 and on the other side of said cross-section, to 
provide a cutting knife 24 which, by means of servo motor 3, is movable 
across the cross-section, there to work in conjunction with the counter 
surface 25. 
The outer bracket 9 comprises an arm constructed as a cutting knife 24 
which works together with countersurface 25 on insert 14 in order to cut 
thread segment 17 from the desired thread end. The inlay 14 is supported 
with a cylindrical surface so that the countersurface 25 fits itself to 
the cutting position of the cutting knife 24. The springs 10 insure that 
the thread segment 17 is held fast by the inner bracket 12 and only then 
does the cutting step take place. 
It is of course advantageous to provide the bracket 12 and the cutting 
knife 24 to be operable by the same servo motor 3 and to be coupled to 
each other over at least one spring. This gives rise to a particularly 
simple form of construction. 
It is also possible to solve this problem of construction by providing 
cutting knife 24 to form a U-shape similar to a second bracket 12 which 
overlaps the first bracket. 
c. Air Blocking Arrangement-- On the upper arm of the outer bracket 9, the 
air cut-off slider 26 is loosely fixed. It comprises a thin plate having 
right-angle bends at both ends. Under the influence of the suction 
provided by suction arrangement 27 in streaming channel 1, the air 
blocking slider 26 is tightly held against surface 28. 
FIG. 3 shows the placement of the combined arrangement 2 in streaming 
channel 1 of such a seeking position. The individual components of the 
construction are disclosed in our co-filed application, MAY 3.0-108, Ser. 
No. 228,056, whose contents are incorporated herein by reference. 
A cop 29 comprises a core 30 on which the thread layer 31 is wound. A 
housing chamber 32 comprising two cylindrical half-shells 33 and 34, as 
well as the bell-shaped head piece 35 having seeking position end 36 of 
streaming channel 11, is provided. The core 30 rests on a cop carrying 
arrangement 37 which can be rotated by means of motor 38 acting over 
friction disk 39. The cop carrying arrangement 37 is movable on conveyor 
40 and carries a peg 41 to take up core 30. The peg 41 comprises a 
streaming path running into the interior of the core from the underside 
thereof comprising, for example, a groove or a bore. 
The height of the streaming channel 1 may be adjusted by means of headpiece 
35. For this purpose, it is connected with arm 43 connected to carrier 44 
and may be moved vertically along vertical guide 46 by means of servo 
motor 45. For the introduction and removal of cops 29, the headpiece 35 is 
raised by the necessary substantial amount and both half-shells 33 and 34 
are correspondingly moved sidewards. Between cop 29 and the housing 
chamber wall, annular space 47 remains, through which an air stream may 
pass under influence of suction arrangement 27. This causes the thread end 
of rotating cop 29 to be loosened and carried into streaming channel 1. In 
order to amplify this effect, there may be utilized the blasting 
arrangement 48, which introduces air in annular space 47, having a 
rotational direction opposite to that of the cop itself. 
In the thread seeking step, the cross-section of the streaming channel 1 
should be burdened as little as possible by the presence of a test and/or 
cutting arrangement. It is therefore advantageous to provide, on one side 
of the cross-section of the streaming channel 1, two clamping surfaces 15 
and 16 (FIGS. 1 and 2) and therebetween a thread probe 18 working together 
with a sensor S, and on the other side of the cross-section, to provide a 
first bracket 9 which is movable across the cross-section by means of a 
servo motor 3 and there to operate in conjunction with the clamping 
surfaces 15, 16. The thread probe 18 responds only to a tightly clamped 
thread segment. Loose threads, thread conglomerations and the like are not 
taken into account. This is in contrast, for example, to testing means 
dependent upon capacitance or optical effects. 
After lapse of an appropriate search time, the head piece 35 is moved 
downwardly by servo motor 45 (Fig. 3) so that the clamping surface 50 
surrounding the search setting end 36 lies against the face end 51 of core 
30. This in turn clamps thread end 49 and holds it in place. At the same 
time, the annular space 47 is isolated from streaming channel 1. There 
thus only remains the streaming through the streaming path 42 via the 
inside of core 30 and streaming channel 1. This ensures that thread end 49 
is held taut. When the servo motor 3 is activated, the testing for the 
presence of thread segment 17, cutting end of thread end 49 to the desired 
length and the closing of the upper portion of streaming channel 1 by air 
cut-off slider 26 takes place. It is advantageous to provide that the air 
cut-off slider 26 is driven by the same servo motor 3 as the first bracket 
and/or the cutting knife. This gives rise to a very simple form of 
construction 
In particular, it is desirable to form this air cut-off slider 26 by a 
loose plate which is carried on an arm of the bracket 9 distal from the 
seeking position end. The plate is thus held closely against its seating 
28 by the force of suction. 
Between the air cut-off slider 26 and the seeking position end, it is 
advantageous to provide at least one air inlet opening 54 (FIG. 3) for the 
provision of an air stream directed towards the seeking position end. By 
means of a thus generated stream, the thread end 49 may be brought into 
the inside of the cop core 30. The air inlet opening 54 may, if desired, 
be combined with an air blast arrangement. It is also possible to provide 
it as closable air inlet opening which opens into the general atmosphere. 
This acts as a suction opening when the counter-stream in the streaming 
channel 1 is provided by suction forces or when the blasting stream pulls 
in extra air by the injection mechanism. 
If no thread is present, the searching step is repeated one or more times. 
For this reason it is advantageous to provide a control arrangement which, 
upon indication of failure of presence of the thread in the testing step, 
permits the cop to remain in the searching position and starts a further 
search cycle. Since the cop 29 is still in the searching position during 
the testing for the thread, the possibility exists to immediately 
recommence a further searching step. This leads to a substantial saving in 
time, since the cop need not be lead to a slide-path to be recycled to the 
search position. 
The control arrangement can be programmed to operate an additional thread 
loosening arrangement in the repeated search step. This increases the 
possibilities of success. Among the possibilities for such a thread 
loosening arrangement, there may be considered means for mechanical 
impacting upon the cop and the like. However, since these require the 
higher consumption of energy or risk damaging the thread, at least one 
search step should be carried out without these additional measures. 
The blasting arrangement 48 can be utilized as an additional thread 
loosening means in the second search step. A further blasting jet 52 can 
be put into operation during the third searching step. 
Thereafter, air is injected in the contrary direction in streaming channel 
1 through air jet arrangement 53. Additionally, by action of the injector 
mode of the air of the jet stream, air is sucked in through opening 54 
which is operated by motion of headpiece 35. During the searching step, 
opening 54 is closed by ring valve 55, but is opened when this is moved 
downwardly into the clamping position. By means of this air stream, thread 
end 49 is driven into the interior of core 30. Thereafter, the housing 
chamber 32 is opened and cop 29 is moved on. 
The above recited embodiments may be varied in several ways without 
departing from the basic concept. For example, the air stream in channel 1 
can be provided solely through use of the blast arrangement 48. Instead of 
blast arrangement 53, there may be provided a suction arrangement at the 
lower end of the cop carrying arrangement, which gives rise to this 
counterstream. Instead of the combined arrangement 2, three individual 
arrangements may be employed which take over the function of the combined 
arrangements.