US2638731A - Control system - Google Patents

Description

May 19, 1953 N. E. KLEIN CONTROL SYSTEM Filed May 1, 1948 7 0 G/P/D 12 I T0 SOURCE OF CON7'RUL PUL S E S Fiji.

T0 Sal RC5 OF CONTROL Pl/L 555 7 0 GRID f2 TOCLUrC/732 INVENTOR NORM/9W E. lfLEl/V active material.

Patented May 19, 1953 CONTROL SYSTEM Norman E. Klein, Stamford, Conn., assignor to Deering Milliken Research Trust, New York, N. Y., a nonprofit trust organized in the State of New York Application May 1, 1948, Serial No. 24,515

Claims.

The present invention relates to control sys-. tems and more particularly to control systems of the type wherein a sequence of control signals controls one ora plurality elements. The invention comprises a novel system of this type wherein the control signals are of random occurrence and of constant or of random duration as desired. The control system of the invention, while of general application, is particularly adapted for use in controlling the manufacture of yarn to insert in the yarn randomly spaced slubs of constant or of random length.

In the control system of the invention inherentlyrandom phenomena, such as the incidence of cosmic radiation on a given surface, are transformed into a series of randomly occurring pulses and the pulses are used to initiate control signals. In one embodiment of the in-- vention, each control signal, once initiated, continues for a period of time which is fixed by the setting of an adjustable member. In other embodiments of the invention, the signals are of random duration or may have any one of a number of randomly selected periods of duration. In the latter case the particular period of duration of any one control signal is unpredictable and is independent of that of the preceding or succeeding signal.

For an understanding or" the invention reference may be had to the accompanying drawing, of which:

Fig. 1 illustrates diagrammatically a control system embodying the invention in which control signals of random occurrence and constant duration control mechanism for insertion of; slubs into yarn; Fig.2 illustrates an alternative arrangement of one part of the system of Fig. 1 for use in inserting slubs of randomly selected lengths into yarn; and i Fig. 3 illustrates a second alternative arrangement of part of the system of Fig. 1 suitable for use in inserting slubs of random length into yarn.

In Fig. 1 a source of random phenomena is diagrammatically indicated at 2 and a device for detecting variations in the source 2 and converting such variations into a sequence of randomly occurring positive electrical pulses is indicated at 4. Source 2 may be, and preferably is, one, or a plurality, of counter tubes actuated upon penetration by cosmic rays or by radiation from radio- Device 4, when source 2 is of the above described type, may be a simple amplifier or a coincident circuit or one or more scale-oftwo circuits, depending upon the number and arrangement of the counter tubes in source 2, upon the type of radiation to which the counter or counters are exposed and upon the desired average rate of initiation of control signals. So far as the present invention is concerned, source 2 may be considered as a conventional cosmic ray actuated counter, such as a Geiger-Muller counter tube and device 4 may be considered as an amplifier and as a means for emitting a positive pulse upon each discharge of the counter of source 2. The randomly occurring positive pulses emitted by device 4 initiate control signals by means of the circuit now to be described.

The positive potential output lead 6 of device 3 is connected over a normally closed back contact 8 of a relay ill, with the control grid ll of a triode Hi. The cathode of triode I4 is connected to an adjustable tap on a resistor 34 con nected across the power source, the positive terminal of which is indicated at 13+. The cathode of tube It thus operates at positive bias. The plate of tube It is connected to 13+ through the winding of the relay Hi and is connected to ground through a condenser it. Control grid I2 is connected to ground through an RC network comprising a resistor I8 and bridging condenser 20. An adjustable contact arm 22 is con nected to a second armature 24 of relay W, the associated front contact 26 of which is connected to control grid [2 through a resistor 28 and the associated back contact 30 of which is connectd to Bl. Each of a plurality of condensers, C1, C2, C3, and C4 of different capacity, has one plate grounded and the other plate connected to a different fixed contact engageable by the contact arm 22.

The above described circuit provides means for initiating energization of relay ID at random intervals and for maintaining the energization of this relay after each initiation thereof for a constant period of time, the length of the period depending upon the capacity of the particular condenser 01, C2, C3 or C4 connected in circuit with arm 22. Thus by adjustment of arm 22, as many different periods of duration of the control signals may be selected as there are different capacities in the condenser array. In the particular embodiment of the invention illustrated in the drawing, four difierent periods of duration can be selected, but obviously additional capacities could be provided, if desired, to increase the range of selection.

Random phenomena occurring in source 2 cause a sequence of positive pulses to be emitted from device l. These positive pulses are separated by periods of random duration, due to the random nature of the source. Each positive pulse is transmitted to the control grid i2 of triode [4 over the circuit including back contact 8 of relay Hi; I Each positive pulse impressed on grid [2 is sufiicient to permit triode It to draw current and thereby energize relay it. Relay Ill, upon energization, picks up its armatures' causing a condenser of the condenser array, specifically condenser C: for the position of arm 22 illustrated in Fig. l, to be connected over front contact 26 and through resistor 28 tocontrol grid I2, and breaking the circuit connecting grid 12 with lead 6 at the back contact 8. The condenser C3 thus discharges to ground through the circuit including resistors 28 and it and this discharge current maintains control grid l2 sufficiently positive to prevent deenergization of tube it for the period of the discharge. Relay I'll is thus also maintained energized during the period'of discharge of condenser C3.

When the potential of control grid 32 drops su fliciently to block tube" i l, relay it? becomes deenergized, condenser C3 is'recharged irom'B-landthe control grid 52 is reconnected to lead tlfor reception of a subsequent positive pulse for initiation of a control signal. A31 heretofore indicated. b adjustment of arm 22 the period of into yarn and for this purposefrelay iii may i cont- 1 the circuit of a device which, when en'- ecreasesthe draft of a yarn drafting ning mechanism, as, r"'or example. by increasing the, rate of rotation of thefee'd or back rolls of the mecahnism, InFig. 1', such a controlleddevice is diagrammatically indicated as a magnetic clutch 32. The energizing circuit ofthe'clutchincludes a pair of terminals 3d,.connected to any suitable source or energy (not shown) an additional armature 3%.: of .rel.ay ill i and a iront contact 38 associated with the a maturefifi. The clutch is thus energized during each control signal. When energized, it couples ,ashait iil to a drive shaft s2 and such coupling through suitable overriding clutches, or the like,

indicated diagrammatically at ti l,- incr'eases the rate of rotation of the driven feed roll 4% of a yarn, drafting and spinning mechanism. The parts of the yarn drafting and spinning mechanism,.other than the roll 36 have not been illustrated inv the, drawing as such mechanisms are well known and form no part of the present invention. It will be understood that during the intervals between control signals, the roll is driven as usual from the main drive shaft i'i of the mechanism at a constant rate of rotation. During control signals, that is during energizaticn of relay Hi and of magnetic clutch 32, the feed; rolls are driven at an increased rate from shaft 42' through shaft ii) andthe overriding clutch i l. The increased rate of rotation of the feed runs decreases the draft r the mechanism and increases the diameter of the yarn and hence randomly spaced slabs of a length determined by the period of duration of the control signals will be inserted in the yarn.

As heretofore indicated, the slubs inserted into the yarn by the system of Fig. 1 will all be of the same length and this length may be changed by adjustment of. the position oi arm 22, to connect a different, one ofthecapacitiesiCi, C2, C3 and C4 to armature 24. Thesystem of Fig. i may be readily modified, if desired, for production of yarn with slubs of different length therein. For this purpose means may be provided for continuously or intermittently moving arm 22 over the fix'ed'contacts connected to the respective' condensers of the array. Fig. 2 illustrates diagrammatically such an arrangement.

In Fig. 2 the four condensers, C1, C2, C3, and C4 are shown with one plate of each connected to a different arcuate conducting segment of a ring 43. The arcuate segments are insulated from each other by short nonconducting segments a.

Theconducting arni 22 is. carriedjby a"sh aft 50 which {is continuously rotated at a' relatively 16w rate by means indicated diagrammaticallyas'a' motor 52, The arm}? is electrically connected by suitable slipringsor brushesKnot showm to the armature 24 of relay [011 Hence, duringim te'r'vals between signals, the condensers are .siiccessivelyconnected to 131+ over the back ontact as associated with v armature as as the end of arm 22 ,in its rotation successivelyjerigages the conducting segments of the ring 48. When relay ,lflis energized oneiof the condensers" C1; 02, c3; and or win discharge'j ovei 'thej circuit comprisingthe armatu e 2'4, front contact Y26 and. resistors 28 andQIBQto hold relay lllceii'ergized for the period of discharge; The ticular' condenser which discharges will depend upon the position of arm 22 at theln ioment of initiation of the control SigriaL. As th. le fig th of time between; any two successive. signals has no relation to the rate of rcitation of arm 22-, the duraticnof anyone sigma will-liavenc rention toy that onneprecedmg or succeeding signal and hence, when slub injecting apparatus is controlled by the. system, theflen gth ofariy one slub .will have no relation tothat of the preceding or succeeding shib, To even-maven short signals that would result when apulse arrives at the grid 12 just prior to' pas sage of the contact arm from a conducting segment or ring 43 and I also to obtain';additional periods of duration i resulting from momentary connection of adjacent v condensers .of the, array in a parallel, heins l ine. s ment 3 ma be ma h r enough to be bridged by the contact arm; 22L:

ea o DIO QiDsfi pl li o cc nden of different capacities for-control f the-durap fthe swiveln s. n F s-- andl'z. a movable plate type of condenser coul dlbe, prov led a ndica d-infer .111 this: r em nt th atur q r a is n td; by su ble S ip }g s or brushes, .not shown; to; a pair of vanes 54 comprising the movable element of a condenser fI he Vanes- M are mounted on a shaft 5 5 ior, rotation therewith: The. fixed elemen ;9 1 th c ndenser .cd rr se a; pair}, or grounded vanes 58; fixedly positioned adjacent the V, vanes 54. H During intervals, between clint c n ithe s during eriod ee rgization of relay l ll, the vanes i 54 are connected tov Bf|- over the back contact 30 QfQarin ature 1 2 O relay 1 .a k h h ft c rry vanes is rotated [by eant: a small 0. 59: Q,:. S, Q lf QQ ifi lOfisly an; dint of the" assembly. Rotation or start as is prefei ably arrested during each control signal and for this purpose the circuit of the motor 60 is controlled over anadditional armature 62 of relay Hi, the energizin circuit of the motor including the armature 62 and a back contact 64 associated therewith. Energy is supplied to the motor 60 from an suitable source of alternating current (not shown), connected to the terminals 66. To provide braking of the motor upon initiation of a control signal, a front contact 68 associated with the armature 62 is connected through a capacity with the back contact 64 and, through a rectifier T2, with that one of the motor terminals connected with the power source. Thus when relay in is energized to pick up its armatures, condenser 19 discharges through the circuit including front'contact 68, armature 62 and the winding of the motor and this discharge current brakes the motor.

With the above described arrangement of Fig. 3, the duration of any control signal willdepend upon the particular position of the vanes 54 at the moment of initiation of the signal, as such position determines the capacity of the condenser and hence the rate of decay of the discharge current through resistance 28 and the network associated with the control grid l2 of the tube controlling relay l0. During intervals between signals, the capacity is continuously varied by rotation of the vanes 54 by the motor I 60 and the condenser is charged from B+ over the back contact 30 of armature 24. Thus this alternative arrangement provides truly random duration ofthe control signals, rather than a random selection of specific durations, as in the arrangement of Fig. 2. Obviously, if desired, a movable plate condenser of the type of Fig. 3, could be substituted for thecondenser array of Fig. 1 wherein a limited number of discrete capacities are available for adjustment of the duration of the control signals.

The control system of the invention has now been described with particular reference to its application to the production of yarn having slubs therein at random intervals and of fixed or of random lengths as desired. In the particular embodiment of the invention illustrated in Fig. l, the control system has been indicated as controlling the insertion of slubs into yarn by increase of the rate of rotation of the feed rolls of a yarn spinning and drafting mechanism to reduce the draft thereof. It will be understood that the draft could be reduced without increase of rate of feed roll rotation, for example by change in ratch length, or by decrease in rate of rotation of the draft rolls or by change of location of feed of the roving into the ratch, in the case of conical feed rolls, and that slubs could be injected into yarn without change of draft, for exampleby the addition of loose fibers to the roving. Also slubs could be injected into continuous filament yarn during extrusion or spinning thereof or during stretch breaking and drafting thereof.

The control system of the invention could be advantageously employed for purposes other than injection of slubs into yarn. For example, novel non-repetitive printing effects on fabrics, or on wall coverings or other surfaces, could be obtained in accordance with the invention by control of a printing element in response to the random control signals, or the random control signals could be used to provide erratic and unpredictable movement of a target in a shooting gallery or unpredictable direction of projection or of time of release of the targets in trap shooting; Other applications of the invention to fields wherein random variations of a characteristic of an article or an erratic sequence of events may be desired will occur to those skilled inthe art.

Obviously various changes, both in the described method of the invention and in the spe cific means illustrated and described herein, could be made without departing from the spirit of the invention. For example, although in the normal practice of the invention the randomly occurring control signals would be utilized concurrently with their production, as described in connection with each of the illustrated embodiments, their use may be delayed if desired, either for predetermined periods, as by inclusion of delay circuits, or for indefinite periods as by inclusion of recording and reproducing means in the system. Also, although in each of the illustrated embodiments of the invention, but one mechanism has been indicated as controlled by the sequence of control signals, obviously any number of mechanisms could be simultaneously controlled in response to the same signals. Also the control signals of random occurrence and as hereinbefore discussed, the source of random phenomena may be any one that is statistically variable, that is, one wherein there are a great number of independently variable elements which are individually unpredictable but collectively stable and the variations thereof susceptible of detection.

The following is claimed:

1. A control system comprising in combination means for detecting randomly occurring radiations, means for producing a sequence of pulses, means responsive to said first mentioned means for initiating a control signal upon the occurrence of a pulse, means responsive to initiation of a control signal for maintaining the control signal for a predetermined period of time, and means associated with said last-mentioned means including a continuously varying element, the position of which at the moment of initiation of a control signal determining the period during which a signal is maintained.

2. A control system comprising in combination, means for producing a sequence of randomly occurring pulses, means for initiating a control signal upon the occurrence of a pulse, a storage device, means for initiating discharge of the storage device upon initiation of a control signal, means responsive to initiation of a control signal for maintaining the control signal for the period of discharge of the storage device, means for recharging the storage device between control signals, and means for continuously varying the capacity of the storage device to randomly vary the period of duration of the randomly produced control signals.

3. A control system comprising in combination a source of random phenomena means for converting phenomena from said source into a series of randomly occurring pulses, a circuit controlling device adapted when energized to produce a control signal, means responsive to a pulse for by thedischarge of sai'd storage device for main taihing said circuit controlling device: energized whereby the period of durationof acontrol Sigrial initiated by a pulse is determined by the capacity of said storage device, and" means' -for' contin'uouslv varyingthe capacity of said st'orage device between fixed limits "during intervals-- he'- tweencoiitrol signals whereby 'the period. of duration-of anycontrol signalis made to depend upom the'capa'cityof said stor'ag'e device-at the moment of initiation of a control signal.

4. The method. of producing a noveityyarnwhicliconipris'e'gcreating a sequence of pulses,

initiatinga control signal in response to a created pulse; initiating discharge of a: storagedevice in response to a control signa1, inaintaining" the signal-during the period of discharge of the storage device and actuating elcrnent affect ing the diameter of yarn for the duration ot the cont-r01 signal.

53 Apparatus for producing yarn having slubs at intervalstherein comprising in combination means for creating a seriesof pulses; means responsive' to a pulse for initiating acont'rol signal, a storage device, means-responsive toa control signal for initiating discharge ofsaid device, means responsive t'odischarge of the storage de-- vice for maintaining the control. signaifor the period oidischarge of the device, a yarn spinning mechanism and means associated therewith and responsive to the control signal for inserting sl'ub's into yarn spun-by said mechanism.

6'; Apparatusaccording toclaim fi-inciuding means for varying the capacityofthe storage device to varycorrespondingly the duration-oi the control signals and the length or slubs'i'nserted into yarn by said mechanism.

7. Apparatus for producing yarn havingrandom'lv spaced siubs therein comprising in combination asource of random-phenomena, means for converting phenomena from said'source int'o a series of randomly-occurring pulses-a normally' deenergized electronic tube connected for energizat-ibir during occurrence of a pulse, a

' storagadevice meansaresponsive to: energization:

of 's'aid tube for: initiating discharge; of-isaidi storage device, .meanszcontrolleds bathedischarge of: said storage device for: maintaining :said; tube 1 energized; ..a yarn spinningrmechanismrandxmeans associated therewith: and responsive;to-venersizae tion: of; said? tube for: inserting, slubs; into, ram spun. by said" mechanism.

8.- Apparatuscaccording;to claim: 7;,including means .for varying; the v. capacity of: said storage device to vary; correspondingly the:- duration; of theperiods of: energization: of saidrtube and- ,the, lengths of theslubsinser-ted into yarn: byr said mechanism;

QFApparatuS: according; to! claim 7. including means. for automatically, vary-ing-;;theicapacitiiiofi said storage device at; least during the intervals, between thepperiodsg-of energization; of said-ttuhe whereby slubs of randomx-lengthr are inserted- 1 into" the yarn;

10;- y The; method of, producing; control: signals which comprises utilizing-asource of inherentlm random; phenomena to create: randomly zoccuraring .pu1ses,, initiating-a controlsignalin response to a created pulse, initiating discharge. of a storage device in response, toa control signal, maintaining the signal during the periodi of discharge of the storage device, 1 and continuously varying the,capacity:of the storage device b.e tween fixed limits to randomly vary'the; period of duration of the randomly-produced control signals.

NORMAN KLEIN. 7

References Cited irrthefile ofthis patent UNITED STATES PATENTS,

Number Name Date;

1,851,090 Fetter Man. :29 1932 138G146 Vingerhoets Nova. 6,; 1935 2,061,011- vingerhoets niuui Nov. 1111-936 2,451,953 Ingram v 0013. 1 19,- 1948 2,471,834 McDowel-l May, 31", 1949 FOREIGN PATENTS" Number Country Date I 315,108 GreatBritain 0t 1929 486,806 Great Britain l June 10,1938 493,974 Great Britain Oct. 18,1938

Images