Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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CONTR01 ARRANGEMENT FOR
YARN PIECING APPARATUS
One proposal made heretofore for improving the
efficiency of operation of a textile yarn forming mill has
been the use of apparatus for replacing the human spinner in
reinstituting yarn formation. Such apparatus are known as
automatic tenders or automatic piecing units and may function
in a variety of different ways, as shown by issued patents
known to persons skilled in the textile arts. One difficulty
encountered with such proposals is the inability of the tender
apparatus to distinguish among those locations along a yarn
forming machine at which reinstitution of yarn formation is
effective and those locations at which it is not effective.
In connection with this problem, practical experience with
apparatus of the type shown and described in previously granted
patents has demonstrated that attempts at reinstitution of yarn
formation are not uniformly successful.
The control arrangements heretofore used with certain
tender apparatus have functioned by detecting any location
along a traversed textile yarn forming machine at which normal
yarn formation has been interrupted. With such detection, a
cycle of operation intended to reinstitute yarn production is
initiated. ~n attempt at reinstitution is made and, on
completion of that at~empt, the tender apparatus is moved from
that location irrespective of success or failure in the
institution of yarn production. Further, the tender apparatus
is in no way responsive to a repeated interruption of yarn
formation which may occur virtually immediately after
reinstitution is successfully accomplished. Understandably,
the number of ineffective attempts at reinstitution of strand
formation can be ~uite high in view of these difficulties.
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An alternate proposal for improving the efficiency of textile ;~
yarn forming operations has involved the use of stop members mounted on
a textile yarn forming machine for interrupting feeding of supply strands
to drafting systems in the event that formation of attenuated strands is
found to have been interrupted. While it will be understood that operations
in accordance with this proposal do not result in reinstitution of yarn
formation, the interruption of supply strand feeding protects the textile
yarn forming machine against risk of damage otherwise possibly occurring
and permits reduction in or elimination of the need for attendance by a
; 10 spinner. Such avoidance of human effort is ob~ained, however, at the cost
of some reduction in production.
In those prior arrangements proposed in efforts to reduce in-
effective attempts at reinstitution of strand formation, reliance has been
placed on relatively sophisticated photoelectric or optical detectors.
Such detectors have presented difficulties, primarily due to certain
unavoidable limitations of the optical systems used and their adaptation
to textile mill environments. Reliable photoelectric detection has been
found to necessitate very accurate alignment and mounting of cooperating
elements, due to depth of field and focus requirements.
According to one aspect of the present invention there is provided
in combination with a textile yarn forming machine having a plurality of
drafting systems arranged at a series of locations for normally receiving
a corresponding series of supply strands and normally delivering a corres-
ponding series of at~enuated strands and a plurality of stop members, each
mounted adjacent a corresponding one of said drafting systems and selectively
actuable for movement between a retracted position spaced from a corresponding
supply strand and a strand interrupting position engaging and restraining the
corresponding supply strand and thereby for interrupting passage of the
restrained supply strand into the corresponding drafting system, and a
traveling unit traversing the machine and having instrumentalities for
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reinstituting attenuated strand formation at a drafting system where an
attenuated strand is absent, an arrangement for facilitating reduction in
the number of ineffective attempts at reinstitution of strand formation and
comprising: active sonic detector means mounted on said traveling unit for
movement therewith along said machine and for electrically signalling
traversal of a drafting sys*em location at which the corresponding one of
said stop members is in the retracted position, attenuated strand detector
means mounted on said traveling unit for movement therewith along said
machine and responsive to electrostatic charges normally present at drating
system locations during attenuated strand formation for electrically signal-
ing traversal of a drafting system location at which normal attenuated strand
formation is occurring, logic circuit means electrically connected with sai.d
sonic detector means and said strand detector means for distinguishing among
signaled traversal of a location at which said corresponding member is in the
retracted position and strand formation is occurring, signaled traversal of
a location at which said corresponding member is in the retracted position
and strand formation has been interrupted, and traversal of a location at
which said corresponding member is in the strand interrupting position, and
control means for responding to said logic circuit means distinguishing
signaled traversal of a location at which said corresponding member is re-
tracted and strand formation has been interrupted by stopping traversal of
said machine by said traveling unit and initiating operation of said instru-
mentalities for reinstituting attenuated strand formation and for responding
to said logic circuit d~stinguishing either of the other traversals by con-
tinuing traversal of said machine by said traveling unit.
According to another aspect of the present invention there is pro-
vided a method of operating a traveling unit which has instrumentalities for
reinstituting attenuated strand formation at drafting systems of a textile
yarn forming machine, the machine having a plurality of drafting systems
3~ arranged at a series of locations for normally receiving a corresponding
series of supply strands and normally delivering a corresponding series
of attenuated strands and having a plurality of stop members each mounted
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adjacent a corresponding one of said draf~ing systems and selectively actuable
for movement between a retracted position spaced from the corresponding supply
strand and a strand interrupting position engaging and restraining the corres-
ponding supply strand and thereby for interrupting passage of the restrained
supply strand into the corresponding drafting system, the method facilitating
reduction in the number of ineffective attempts at reinstitution of strand
formation and comprising the steps of: traversing the drafting system loca-
tions with the traveling unit while actively sonically det0cting the disposi-
tion of stop members in the retracted position and electrostatically
detecting electrical charges normally present at drafting system locations
during attenuated strand formation, electrically signaling traversal of a
drafting system location at which the corresponding stop member is in the
retracted position, electrically signaling traversal of a drafting system
location where normal attenuated strand production is occurring, distin-
guishing among signaled traversal of a location at which said :corresponding
stop member is in the retracted position and strand formation is occurring,
signaled traversal of a location at which said corresponding stop member i5 in
the retracted position and strand formation has been interrupted, and traversal
of a location at which said corresponding stop member is in the interrupting
position, continuing traversal of the textile machine by the traveling unit
in response to distinguishing signaled traversal of a location at which strand
formation is occurring and traversal of a location at which the corresponding
stop member is in the interrupting position, and interrupting traversal of the
traveling unit and initiating operation of the instrumentalities for re-
instituting formation of attenuated strands in response to distinguishing the
signaled traversal of a location at which said corresponding stop member is
in the retracted position and strand formation has been interrupted.
In the accompanying drawings which illustrate exemplary embodi-
ments of the present invention:
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Figure 1 is an elevation view, partly broken away, of a first
embodiment of the apparatus;
Figure 2 is a schematic perspective view of certain detectors
and textile yarn forming machine elements involved in the apparatus;
Figure 3 is a block diagram of certain functions of a control
arrangement;
Figure 4 is a partially schematic drawing of certain electrical
circuitry involved in the apparatus; and
Figure 5 is a view similar to Figure 1 of a second embodiment
of the apparatus.
While e~bodiments of this invention will be described herein-
a~ter with particular reerence to the accompanying drawings, briefly des-
cribed above, it is to be realized at the outset of this description that
the present invention is contemplated as being of broad usefulness to persons
skilled in those branches of the textile arts to which this invention per-
tains. Accordingly, the illustration and description of particular embodi-
ments of the invention are not to be understood as being restrictive upon
the scope of application of this invention, but are to be taken broadly as
teachings of the best mode known at the time that the illustrations and
2a description were prepared.
This invention is related to certain inventions described in pre-
viously granted patents which are owned in common. These patents include
Lee, Jr. et al United States Patent 3,486,319 granted December 30, 1969;
Mulligan United States Patent 3,623,310 granted November 30, 1971;
Saunders United States Patent 3,659,409 granted May 2, 1972; Ford et al
United States Patent 3,726,072 granted April 3, 1973; and Lee, Jr. United
Stated Patent 3,754,992 granted August 28, 1973. Interested readers are
directed to those prior paten~s for further information concerning the art
to which the present invention pertains.
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Figure 1 of the accompanying drawings shows a textile
yarn forming machine, generally indicated at 10, having a
plurality of drafting systems generally indicated at 11. As
is known, each of the drafting systems includes a series of
pairs of rolls 12, 13, 14 (Figure 2) for normally receiving a
supply strand S and normally delivering an attenuated strand Y.
The machine 10 has a plurality of drafting systems arranged
at a series of locations, so that the drafting systems receive
a corresponding series of supply strands and deliver a
corresponding series of attenuated strands or yarns.
A plurality of stop members 16 are provided for
cooperation with the machine 10. Each o the stop members 16
is mounted adiacent a corresponding one of the drating
systems 11 and is selectively actuable for movement between a
retracted position (Figures 1 and 2~ spaced from a corresponding
supply strand S and a strand interrupting position engaging and
restraining the corresponding supply strand. When the stop
member 16 is in the strand interrupting position, passage of
the supply strand S into the corresponding drafting system 11
is interrupted, thereby precluding formation of an attenuated
strand or reinstitution of attenuated strand formation.
A traveling unit generally indicated at 20 traverses
the textile yarn forming machine 10 and has instrumentalities
tnot sh~wn in detail in the accompanying drawings) for
reinstituting attenuated strand formation at a drafting system
where an attenuated strand is absent. In the form illustrated
in Figure 1, the traveling unit 20 is a traveling pneumatic
cleaner supported upon the track 21 which extends over the
textile machine 10 and having a blowing cleaning member 22
and a suction cleaning member 24 which depend to one side of
the traveling cleaner 10. The instrumentalities for
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reinstituting attenuated strand formation are mounted within
a casing 25 disposed between the cleaning members 22, 24,
Additional support for the casing 25 is provided by an auxiliary
lower rail 26 extending along the lower portion of the textile
machine 10. It will be understood by persons familiar with
the textile art to which this invention pertains that the exact
construction and operation of the instrumentalities for
reinstituting attenuated strand formation may be in accordance
with a number of known and available prior disclosures, including
Lee, Jr. et al U. S. Patent 3,486,319 and earlier patents
referred to therein. It is for this reason that it is not
deemed necessary to extend the present description by repetition
o illustrations and description available elsewhere.
In accordance with the present invention, an active
sonic detector means is mounted on the traveling unit 20 for
movement therewith along the machine 10 and for electrically
signaling traversal of a drafting system location at which
the corresponding one of the stop memkers 16 is in the retracted
position. In the form shown, the active sonic detector means
comprises an ultrasonic transmitter 30 and an ultrasonic
receiver31. By means of the ultrasonic transmitter 30, a
relatively tight beam of ultrasonic energy is emitted and is
directed from the traveling unit 20 toward the textile machine
10. Preferably, the active sonic detector means is mounted in
the casing 25, for projection of the beam of ultrasonic energy
in a plane perpendicular to a generally planar surface of the
stop members 16. Reflection of the beam of sonic energy from
a stop member 16 in the retracted position (Figure 2) results
in reception of sonic energy by the receiver 31. Where a
stop member 16 is in the strand interrupting position, the
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tight beam of sonic energy does not impinge upon the stop
member and is not reflected to the receiver 31. Accordingly,
no electrical signal is generated by the active sonic detection
means upon traversal of a drafting system location at which the
corresponding one of the stop members 16 has been actuated
to move to the strand interrupting position. It will be
understood that, as used in this description, reference to an
"active" detector includes particularly those arrangements
wherein a signal or energy beam is generated and emitted with
the reflection or echo of that energy beam beiny received and
detected. Further, it will be understood that reference to
a "sonic" detector contemplates a detector which makes use of
vibrating energy close to those frequencies detected by the
human ear, although preferably the frequency range is in the
range denominated as ultrasonic and at frequencies above the
range of the human ear. These arrangements are distinct from
detector arrangements which rely upon the use of a light and
may be known as photoelectric, as experience has demonstrated
that photoelectric detection systems may be subject to
difficulties arising from depth o field and focus of optical
systems which are not encountered with the use of active sonic
detectors.
The traveling unit 20 also has mounted thereon for
movement therewith along the machine 10 an attenuated strand
detector generally indicated at 32 which is responsive to
electrostatic charges normally present at drafting system
locations during attenuated strand formation. The electrostatic
detector 32 electrically signals traversal of a drafting system
location at which normal attenuated strand formation is occur-
ring. Preferably, the electrostatic detector 32 is mounted
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within the casing 25 at a location adjacent the path followed
by attenuated strands Y in movement from the delivery rolls 12
of the drafting systems to bobbins on which the strands are
wound.
The electrostatic detector 32 comprises an electrically
floating detector rod 34 and circuitry (schematically shown in
Figure 4) for responding to fluctuation in electrostatic charges
near the rod 34, all as described more fully hereinafter. The
general cooperation between the electrostatic end detector 32
and the ultrasonic detector means may be understood from the
block diagram of Fiyure 3, in which it is indicated that
electrical signals generated by the detectors cooperate in
initiating a controlled function (such as that accomplished by
the rnechanism illustrated in Fiyures 22, 23 of ~ee, Jr., et al
U. S. Patent No. 3,486,319 and described in that patent with
reference to those figures). The controlled function, as
described more fully hereinafter, may additionally govern
feed stop actuation (generally through use of an arrangement
such as that of Figure 11 of Ford et al U. S. Patent 3,726,072
and as described in that patent with reference to that figure).
A more specific understanding of the manner in
which the detector means cooperate may be gained from description
with reference to Figure 4. As is there shown, fluctuation in
electrostatic charges near the rod 34 are applied through FET
and other transistors and associated resistors and capacitors
to provide an electrical output to a bistable multivibrator
or flip-flop 35 which, together with a gate device 36, forms
a logic circuit means. The logic circuit means is electrically
connected with the receiver 31 of the active sonic detector and
with the electrostatic detector 32 for distinguishing among
three possible conditions.
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The logic circuit means distinguishes among; (1)
signaled traversal of a location at which the corresponding
stop member 16 is in the retracted position and strand ~ormation
is occurring; (2) signaled traversal of a location at which
the stop member 16 is in the retracted position and strand
formation has been interrupted (as in an "end down" condition);
and (3) traversal of a location at which the stop member 16
is in the strand interrupting position. The logic circuit
means preferably is arranged to provide an output only in
instances of the second of the listed conditions. More
particularly, reflection of ultrasonic energy from a stop
member 16 to the receiver 31 (Figure ~) generates an electrical
signal which, when passed through an amplifier 38, is effective
to energize coil 39 of a relay. The relay coil 39, when
energized, closes an associated contact 40 which applies an
electrical signal to the multivibrator 35 and gate device 36.
Thus, the multivibrator device is set to a first condition and
is prepared to receive a signal through the electrostatic
detector 32 in the event that normal attenuated yarn formation
is proceeding. In the event that normal attenuated yarn
formation is proceeding, an electrical signal derived rom
the exposure of the rod 34 to electrostatic charges passes
to the multivibrator 35, resetting the multivibrator to an
alternate condition and removing from the gate device the
signal which would otherwise be passed through the multivibrator
35. The gate device 36 is selected to be of a type which passes
an output signal only in the instances that two signals are
applied thereto (an "and" gate).
In the event that normal attenuated strand formation
has been interrupted, no signal passes from the electrostatic
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detector 32 to the multivibrator 35, and thus two signals
continue to be applied to the gate device 36 and an output
signal is provided. This output signal may then be used to
actuate control arrangements as referred to hereinabove.
In the event that the corresponding stop member 16
has been pivoted to the actuated or feed stop position, no
sonic energy is reflected to receiver 31, the relay contacts 40
are not closed, and no signals are appliecl to the multivibrator
35 or gate device 36.
This invention contemplates that the electrostatic
detector 32 may be employed to check proper reinstitution of
yarn formation prior to release of the traveling unit 20 for
continuiny traversal of the textile machine 10. I~l such an
arrangement, the control for the instrumentalities which
reinstitute yarn formation would be arranyed to reset the
detectors and logic circuit on completion of a cycle of
operation of the instrumentalities. With resetting of the
detectors, while the stop member 16 continues in the retracted
position, the presence of electrostatic charges following
successful reinstitution of yarn formation would preclude
passage of a siynal through the logic circuit means and would
release the traveling unit 20 for continued traversal of the
textile machine 10. In the event of an unsuccessful attempt
at reinstitution of yarn formation, electrostatic charges
indicative of attenuated strand formation would be absent, and
a successive cycle of operation of the instrumentalities could
be initiated.
Following one or more repetition of cycles of
operation of the instrumentalities, with continuing failure
to successfully reinstitute attenuated strand formation~ it
is contemplated that the control arrangement would pass a
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signal to a feed stop actuation device 41, supplied with air
under pressure through a conduit 42 communicating with a fan
portion of the traveling cleaner 20 as briefly indlcated above
by reference to related U. S. Patent 3,726,072. Thus, an "air
; bullet" would be directed against the stop member 16, pivoting
the stop member to the strand interrupting position. With
movement of the member 16 to strand interrupting position, the
corresponding drafting system location would be assured of
falling into the third of the distinguished conditions described
hereinabove and no further attempts at reinstitution of yarn
formation at that drafting system location would be made
until such time as an operator attending the machine corrected
the difficulty which caused the traveling unit to fail. It is
in this manner that the number of ineffective attempts at
reinstitution of strand formation is reduced in accordance with
this invention.
It is contempated that the advantages of this invention
are equally applicable to traveling units of a type different
from that described to this point. Accordingly, a different
variety of traveling unit, indicated generally at 20', has
been illustrated in Figure 5. Prinle notation has been used
to identify portions of the combination illustrated in
Figure 5 corresponding with portions described with reference
to Figures 1-4, in order to aid understanding of the application
of this invention to such an alternative traveling unit 20'.
As will be recognized, the traveling unit 20' is supported by
upper and lower rails 21l, 26' and is provided with an active
sonic detector means having a transmitter 30l and a receiver
31l and with an attenuated strand detector means 32'.
Additionally, the traveling unit 20' is equipped with an
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appropriate means 41' for remotely actuating feed stop members
16' as necessary in a~cordance with this invention.
In the drawings and specification~ there has been set
forth a preferred embodiment of the invention, and although
specific terms are employed, they are used in a generic and
descriptive sense only and not for purposes of limitation.
