US2644221A - Stop motion for textile machines - Google Patents

Description

July 7, 1953 P. N. SMITH 7 STOP MOTION FOR TEXTILE MACHINES Filed Dec. 5, 1950 INVENTOR PHILIP SMITH z. %Z)T ATTORNEY Patented July 7, 1953 STOP. MOTION FOR TEXTILE MACHINES Philip N. Smith, Clemson, S. 0., assignor to Deering Milliken Research Trust, Pendleton, S. 0., a nonprofit trust of Maine Application December 5, 1950, Serial No. 199,314

6 Claims.

therefore be described with reference thereto;

An electronic warper stop motion which is now in commercial use and which has been found to give satisfaction in operation is one in which ungrounded drop wires associated with threads coming from one side of a creel are connected through a resistor to the control gridof a normally ener-'- gized electronic tube to cause deenergization of the tube ,upon grounding of a drop wire resulting from breakage of an associated thread, deenergization of the tube causing a relay toopen the circuit of the motor advancing the thread and causing a signal lamp to belighted. Similarly,

in the above mentioned device, the ungroun'ded drop wires associated with the threads'coming irom the other side of the creel are connected through a resistor to the control grid of a sec-- ond normally energized electronic tube to cause deenergization of the tube upon grounding of a drop wire and opening'of the circuit of the motor and lighting of a signal lamp, an interlocking circuit being provided to prevent the closure of the circuit of one lam-p after that of the other has been completed.

The above broadly described stop motion, as

originally designed, required a relatively large number of components, some of which had to operate close to their rated tolerances. It was also relatively expensive to manufacture; A more recent version of such stop motion is a decided improvement over the original device in that :fewerelement's' are utilized and the components thereof can operate well within their rated tolerances. This later version, however, has the drawback that the'relays thereof tend to chatter when ends in differentsections of the creel come'd'own in rapid succession, that is, when the second end comes down before the relay' responsive to the coming down of the first end has had time to release. The improved circuit of the present in vention, while retaining all of the advantages of the simplified circuit of the above mentioned later stop-motion device overcomes this tendency of the relays to chatter and thus insures positive operation of the device irrespective of the length of time between successive coming down of ends. r V

The single figure of the drawing illustrates a schematic perspective view of the essential elements of a stop-motion device for use in association with a warper and includes a circuit dia gramof the new electrical circuitof the inventionr Inflthe drawing, 'a warper creel is indicated diagrammatically at l as composed of vertical bars. 2, each carrying a plurality of cones of thread 3;, The threads are drawnthrougha comb uea warp beam 5, which is rotated by a motor M. "The improved device of this invention pro; vides'two terminalvb'ars 1 and 8, which are respectively associated with the left side and right side of the creel, said bars being positioned transversely of the direction of travel of the threads. Eachterminal bar has a multiplicity of drop wires '9 radially displaceable with respect to the bar and electrically connected thereto. These drop wires are upwardly bent, and each has 'a small aperture or eye It) at the end remote from .the connection to the terminal bar, said eye be- .ing adapted for passage therethrough of a thread. A metalcontactbar H is positioned below and substantially parallel to the two terminal bars 7 and at a distance therefrom such that the drop wires ",9 .ifnake contact therewith when released by:

bar l and associated with the left-hand section of the creel Land the other containing an'electronic tube V" whichis similarly responsiveto closure ,o f;th, e circuit between the right-hand terminal bar I; and the'groundbar H. The left-hand terminal bar 1 is connected through a current 'limitingre s'istor llito the control grid Id of tube V. Control grid 14 is also connected to ground wire ,l2 through resistors 15, I1 and 22. The cathode 18 of tubeVis connected directly to line 16. The plate [9 of tube V is connected through the energizing winding of relay R to a sourceqof highlpotential' comprising the rectified .andifile 'tere'd output from the secondary winding 2010i 3 a step-up transformer 2 I. One end of winding 20 is connected to ground wire l2 and the other end is connected to the anode of a diode rectifier 23, the cathode of which is connected through relay R to the anode of tube V and through relay R to the anode of tube V. A separate winding 24 of transformer 21 serves for :energizationof the cathode of diod'e 23. One electrode of a condenser 25 is connected to the cathode of rectifier 23 and the other electrode is connected to the junction of resistors I! and 22. The primary winding 26 of transformer 21 is connected through suitable fuses ,f and ,a .switch S to alternating current supply lines '21. A Winding28 on transformer 2! is provided to supply current to the cathode heaters of tubes V and V through conductors arr (not shown). -'A pilot lamp? is connected across the winding 28 to signify when power is on.

The connection from the right-hand terminal bar 8 of the warper to the" tube V and the circuit connections of this tube are substantially identical to those of tube 'V. In the drawing, each element of theioircuit of tube'V corresponding to a similar elementin the circuit of tube "V is indicated by the same reference character but with a prime addedthereto. RelayR has two armatures .29 and 30,1the former of which over a back contact controls "an alternative circuitfor relay R and the latter of whichovera back contact controls the circuit fora signal llight Li .and over a front contact controls thecircuitlof a motor controllingrelay Similarly, .relay R has two armatures :29 and 30 controlling, respectively, an :alterna- ,tive circuit. forrelayR and the circuits of .asi'gna'l lamp Rtand .of the .relay .R.-M. The alternative circuitfor .relay R comprisesla'flead 3| connectingthe anode [9 of tube V with armature .29 of relay .R' .and a resistor -'32, one end or which is connected .to the hack contacts 33 and 33 associated respectively with. armatures 29 .and-29' :and the other end .of which .connected to lead 16. Thealternative circuit for .re'layiR comprises alead-3|connectingtheanode IQ of tube V with armature 29 andmesistorBZ.

The-circuit for signal ,lamp .R't may be traced as follows: from one power. line-21 throughswitch S and 'a fuse through .leads 34, .35 .and 36 .to lamp .Rt, .from lamp Rt through .a.=lead 37" to leadr39 to 'afrontcontact 40 of armature 3'0, armature 30 andalead 4! backto .the otherpower line ZIthroughgiuse f.and.switch E. .'.The circuit of .signal lamp Lt comprises vleads I34, '35 rand .36, the .lamp Lt,-.lead :31, .back contact 38 of armature 3B, armature 30 .and lead 14.1. .Jil'esistor has .one .end .connected to .the hig'hflpottential 1 end -of relaysR .andR' audits other .end connected to line 16, a condenser .43 .beingconlocated across the resistorAZ.

#Ihe energizing coil of motortcontrol relay :R--M.is connected-acrossslead 34 and front con- :taotflfl' of :armaturetfl'. .It .will beunderstood thatcommercial warpers use variousdifierent electrical systems to :control .the drivebeam. Safety circuits to prevent overheating. orthe. like, iand stop, start and jQgsWitches areordi- -narily;provided. In order to indicate how the stopemotion 1 device of the present invention can he readilycoupled with such other circuits .arelay Ca iSindicated in the drawing as controllinga switch Min the lead'45 connecting the front contact!!! .of armature 3'0 withrelay and a relay Cs'is indicated'as controlling "a "switch "46 in a line 41 bridging the contacts controlled by relays R and R. Relay CR is intended to symbolize any relay of such safety system that is normally energized during operation of a the warper and relay Cs one that is normally deenergized but is adapted to be energized during closure of start and jog switches. The motor for driving the-warp beam is connected across suitable supply lines 48 through the armature -49 of relay RM and a front contact 50 associated therewith.

With "the circuit arrangement just described, when switch sis closed, power is supplied to the .cathodelheaters of tubes V and V from winding .28. .-At the-same time the cathode of rectifier 23 is heated from winding 24 causing the rectifier to pass-current on alternate half cycles of the impressed voltage wave. Operating potential is then impressed through the windings of relays Rand R, respectivelyfupon the, platesof tubes V and V. "Until the warp "beam is started the threads from the creel will be slack =&Ild CO1fl seguen'tly the :control grids of tubes V andV"will be grounded through the drop "wires 9 and ground bar .I I, biasing the tubes tocuteo'ffp jThe current flowing through .resistor '42 provides'ia potential difference acrossres'istors" l1 and? Z'su'fficient to maintain line lfi and 'thereforealso the cathodes of 'tubesof'v and V at'above ground potential. .Relay'R .or relay .R", depending upon which has the quicker response, will become eiier gizedover its alternate circuit .includingf'bacl; contacts of the other .relay .and,. onceienerg"igejd will hold open .the alternate circuit of the "other relay. When, however, the "beam :is, startedf'fby closure of the starting circuit including Switch 4.6, .the threads arebrought under tens'ionandthe .drop wiresmoved-outof contact with the ground bar ll. .Tubes Vtand V will fthereupon"'both pass .currentand both .relaysR and R" will be energized and their .armatures will. complete the holding circuit .for the -motor controlling, .re'lay R-.M which thus -is maintained energized after openingofthestartingrcircuit. f

If now .a thread breaks, for example, one com; ing. from theleftside of the creel, the associated ,drop wire .9 .drops .and makes contact 'with ground bar ll, grounding bar fllandbringingfthe potential of grid -l.4l.of tube 'V below that ofthe cathode .IB. Tube V therefore becomes ..deener+ :gized, ..deenergizing.relay.R. .Relay R thereupon .drops its armatures, closing the circuit of lamp Lt over the back contact of armature 3.0 and open:- .ing .the -circuit .of .relay R-M .at ;the..front .con- .tact ofiarmature 30. .Theresultingdeenergizae .tion .of relay .R M opens. .thercircuit oftheiheam motor M.at .contact.'5.0. "Whenthebeani stops rotating, .all threads '..are .sl-acked .andLhence the control grid .of tube V will be groundedQand that tube will .also cease passingcurrent. Relay .R v will .not, however, become JdeenergiZed asji'ts alternative circuit throughresistor 3210 lead 16 wasclosed at thebackcontact 3.3 ..of armature 1 9 .when .relay 30 becamedeenergized. Lamp Rt ,will.-not be lightedasits circuit will remain QP I .at the back contact .of armature .305 rIhus,

.upon stoppage cf. the warp beam due to a' broken thread, the operator can tell by thelli'g'hting'of lamp Lt thatthe broken threadis on'the leftside or the creel. "Similarly when relay'JR-Mde lenergized as a .result of *aithread "break "on the right side of the creel relay R is deenergized upon deenergization of tube V, relay His maintained "energized "over its"alternative'circuit in "cluding' the 'back "contact of armature -29, the

circuit'of lamp Rt is completed over the back contact of armature 30 and that of relay R-M is opened at the front contact of armature 30'. The lamp Lt will not light as its circuit is open at the back contact of armature 30. Should an end in the right side of the creel, for example, come down after one has come down on the left side of the creel but before the back contacts of relay R have closed, tube V will also become deenergized but because of the potential drop across resistors I! and 22 the potential of the cathodes will be held positive and the tubes will remain deenergized, thus insuring closure of the back contacts of relay B and energizing current for relay R. It is the provision of resistor 42 in the circuit which insures that the cathodes of tubes V and V will remain at positive potential at all times and thus prevents reenergiz-ation of a tube While an end associated therewith is still down. In the absence of resistor 42 when both tubes are deenergized prior to closure of the alternate circuit of either relay no current flows through resistors i1 and 22 and hence the cathodes of the tubes are grounded and momentary reenergization of one or the other of the tubes occurs and chattering of the relays results.

From the foregoing description of one specific embodiment of the invention, it will be apparent that the new stop-motion insures stopping of the warp beam upon breakage or slackness of a thread and provides a signal indicative of the location of the thread break which continues after all threads are slacked as a result of beam stoppage. The new circuit requires but few components, it is easy to install and to service and does not interfere with the operation of other safety circuits that may be in use with the particular warper to be controlled.

By way of illustration, but not of limitation, the circuit constants will now be given of one specific circuit which has been found particularly satisfactory with high speed warpers now in commercial use. In such circuit, tubes V and V were halves of a double triode, a 6SN'7, diode 22 was a 5Y3, resistors i3 and I3 were each 2 megohms, resistors l5 and I5 were each .47 megohm, resistors i1 and 22 were each 5 kilohms, resistor 32 was 4.7 kilohms, lines 21 were 110 volt, 60 cycle power lines, and condensers 25 and 43 each had a capacity of 1 microfarad. The voltages of windings 24 and 28 were 5 volts and 6 volts, respectively, and that of secondary 20 was 700 volts.

The invention has now been described with reference to one specific embodiment thereof. Obviously, various changes in the particular circuit illustrated and described could be made without departing from the spirit of the invention or the scope of the accompanying claims, For example, although the invention has been described with reference to the preferred embodiment of the invention wherein indications are given of a yarn break in but two divisions of the creel, either the right side or the left side, the system can be readily expanded to indicate a yarn break in more than two divisions as Will be readily apparent to those skilled in the art. If indications of a yarn break in a third division, for example in the center of the creel, are desired, it is only necessary to provide a third circuit, comprising a series connected relay and tube connected across the power supply with the control grid of the tube connected through a resistor with drop wires associated with the threads of such third division and to provide a third indicator lamp controlled by such third relay. The motor control relay Gil circuit would then be controlled over back con tacts of the other relays as in the illustrated embodiment of the invention.

Furthermore, although thebars supporting the drop wires have been'described as normally insulated from the ground, these bars could be grounded by connection to the ground wire of the circuit, in which case the contact bar would be divided into sections corresponding to the differentparts of the creel and these sections-connect ed respectively to the current limiting resistors in the grid circuits of the tubes. These and other variations and modifications are believed to be within the scope of the invention as describedin the specifications and defined in the appended claims. Y

The following is claimed:

1. 'In a textile machine the combination comprising means for advancing a plurality of threads under'tension, a guide means associated with each thread adapted to be moved when its associatedthread is slacked, a pair of contacts associated with each guide means, means grounding one only of each pair of contacts, a pair of electronic tubes each having a cathode, a control grid and an anode, a resistor connected at one end to the control grid of one of said tubes and at its other end to the ungrounded one of certain of said pairs of contacts, a resistor connected at one end to the control grid of the other of said tubes and at its other end to the ungrounded one of certain other of. said pairs of contacts, a source of energy, a pair of relays, the anode of each tube being connected to the high potential end of said source through one of said relays, grid leak resistors for said tubes, a common cathode resistor connecting the oathodes of said tube with the low potential end of said source, said low potential end of said source being grounded, whereby said tubes and relays are all energized when the threads are under tension but upon slackness of any one of the threads and consequent grounding of the control grid connected to the contact of the pair of contacts associated with the guide means for such thread the tube controlled thereby is deenergized and breaks the circuit of the relay connected thereto, means responsive to release of either relay for stopping said first mentioned means, means operative upon release of either relay to maintain the other relay energized, and means for maintaining a potential difference across said cathode resistor independently of the state of energization or deenergization of said tubes.

2. The combination according to claim 1 wherein said last mentioned means comprises a resistor connected at one end to the high potential end of said source and at its other end to the cathodes of said tubes.

3. In a warper stop motion device of the type wherein the control grid of a normally energized tube having also a cathode and anode is grounded through a wire when a thread breaks and deenergization of the tube releases a relay in series therewith across a source of energy the low potential end of which is grounded, the relay when released initiating stoppage of the warper, ,the improvement comprising a cathode resistor connected between the'cathode of the tube and the low potential end of said source and means independent of the energization of said tube for maintaining a potential difference across said cathode resistor to prevent reenergization of the 7 tube while the control grid is grounded through a drop wire.

4. The combination according to claim 3 wherein said last mentioned means comprises a resistor connected-in shunt with said relay and tube.

5. In a stop motion circuit of the type wherein a plurality of normally energized electronic tubes'each having an anode, a control grid and a cathode, have their control grids connected to different groups of drop wires of a textile thread advancing machine, their anodes connected through difierent relay windings to the high potential end of a source of energy and their cathodes connected to the grounded low potential end of the source through a common cathode resistor andwherein release of a relay resulting from the grounding through adrop wire of the control grid of thetube in serieswith such relay initiates stopping of the thread ad- PI-IEHIIP N. SLH'I'I'I.

References Cited in the file of this patent UNITED STATES PATENTS Name Date Anderson Oct. 2, 1951 Number

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