US2540673A

US2540673A - Picker stick linkage and hydraulic check

Info

Publication number: US2540673A
Application number: US782341A
Authority: US
Inventors: George H Hufferd
Original assignee: Weatherhead Co
Current assignee: Weatherhead Co
Priority date: 1947-10-27
Filing date: 1947-10-27
Publication date: 1951-02-06
Anticipated expiration: 1968-02-06

Description

Feb. 6, 1951 s. H. HUFFERD 2,540,673

PICKER STICK LINKAGE AND HYDRAULIC CHECK Filed Oct. 2'7, 1947 2 Sheets-Sheet l INVENTOR. GEORGE H.HU FFER D.

ATTORNEYS.

Feb. 6, 1951 HUFFERD 2,540,673

PICKER STICK LINKAGE AND HYDRAULIC CHECK Filed 001;. 27, 1947 2 Sheets-Sheet 2 INVENTOR.

GEORGE H. HUF'FERD.

ATTQRLEYS.

PatentedFeb. 6, 1951 CHE George. H. Huffe'rd; Shaker Heights; Ohio, as" signer to The. Weatherhead Company; .Cle'v'e-=- land, Ohio, a corporation-vof-flhio Application October-27, 1947, Serial No. 782,341

25'Claims. 1. This? invention" relates to' looms" and" more specifically to anovel mounting means for the picker. stickthat castsa shuttle to and 'fro'across thetz-shed.

Th'eqloom; of the. type to which this invention relates employs'a pair of opposed picker sticks which. rock: back and: forth with the lay assembly'fand alternately castand receive the shuttle.:. Formerly, such loom's' operated at a com-- paratively slow: rate. of: speed, the arrangement being that the shuttle'boxchecked-and absorbed thevshuttle energy an'd a leather strap or similar device was:employeditoistop and check the picker sticks. Recently, workers have striven for increased speed of .operatiombut this'has presented.

several problems Whereinprior equipment has provenunsatisfactory. and? erratic in its opera-- tion; It'was found that the. old strap checking device .is deficient because. with an increased shuttlei speed the shuttle:boxican no longerabsorb all of the energy of the flying shuttlef-whereupon; the shuttle; strikes Tthe picker: stick and forces it against .the check. strap, causing rebound; Difiicultiesof this'nature 02.11 be ilargely overcome by: the? provision of novel. hydraulic checking devicesysuch as :those described: in copendihg: applications assigned" to the asignee of 2 this application;..namely Serial No'. 670,25'2,--fi1ed May 16, 1946, now Patent No, 2,483,517; Se'rialNo; 702,953, filed-October: 12, 1946; now "Patent No. 2,506,697, and Serials-No. 782,342, filed' ioctobeit:

Although said .novel' hydraulic checking jdevices.- greatly improve 1 the. action. of f the i loom,

severahproblerns remain unsolved; Fortexample,

it..:was customary in-ra' IargeLand representative t class of looms to mount. the:pickerstick ona curved-.ishoe, urged against a flat plate by a strap and: .coil. spring iassembly. tax-produce .a' straight line motion to the picker head, but it proved to be an impractical construetion: when speeds were increased;- It wassfound that the shoe tends. to leave the plateunder. .aeeti'onof the propelling strap as..we1l asWhenZthe shuttle. zstrikes thespic'ker head; This "producesi erratici-casti'ng. of the shuttle and makes a unif orzn echecking .action difficult. to obtain. Furthermore; there was no positive controller" the path traversed by-thepickerphead and adjustment of;

therpatir was impossible:

It isaniob-ject of the present invention to causa thetspicker'; head .to' positively and. accurately. traverse a desired rpath :by mounting theLpic-Ker head uponiarsetiof linksso. that nocforces .n 2-.

This was .-arranged mall-y encountereduduiiing-; operation :oii Lthfi looms 2: can cause deviations'in the'patliof travel of the" picker."

It is inherent that since the shuttle initially rests'in a track there is no danger of its being deflected downwardly before it traverses the" shed, but if the picker action is improper the shuttle m'ay be deflected upwardly whereupon the nose or perhaps the entire shuttle might leave the track and not 'en'ter the-shed'properly'. It is another object of the "present invention to insure that the shuttle is 'ca'st'without tendencytojump in'g 'o'r nosingum whichpbject isa'ttained by the aforesaid linkage. slightly rising picker motion during the final'portion' of the power stroke whereby the nose 'of thej shuttleis urged'downwardly against its track and so has no tendency to jurnp clear 'ofi thetra'cke It is a further object to 'guide the picker head in a substantially straight line I from its neutral position (where itre'civesthesliiittle impact)" to its 'rearmost or checked 'positionl' making it 'pos The said linkage provides a' sible to accurately a'dj'ust the hyd'raulic checking" device' sothat. the "shuttle and p'icker arebrought toa dead stop without reboundl 7 As' mentionedinthe aforesaid pending a'p'pli cations, where the picker stick must "absorb en ergy of the shuttle and bring "the shuttle to -a stop? without I rebound, it is T important that the picker stick aiwaysr'eturn to approximately the same position (referred to as' 'the"nei1tral position hereafter) when'it'receivesthe impactfof the flying shuttle. outlined in" said applications, when in the neutral According to the "principles position the arrangement is such that hydraulic i checking action begin'sa'nd continues throughout the balance of the return' stroke. Accordingly; it iside'sir able that nleans be provided to bring the picker stick: to said neutral position, and it is furtherdesirablethat such means offer little resistance-to motion'ofthe picker stick and shut tle as 'they' move' from the neutral position to the en'd' of their return or check stroke.

Therefore; it is""a further object of "the" present invention' to so bia's'the picker stick that it is strongly urged to move from theend' of the power stroke to the neutral position; but is urg'e'dby a muchsmallerforce to movefrom the end of the check stroke to theneutral position, With this arrangement, a 'cornparatively'smallresilient resistan'ce isofiered tothefinal checki'n'g' of the shuttle and picken whereby rebound is elimi nated: sembly of th'epicker stickand the links which According to this invention; the asguide it actso that theweight of "the parts' tnds to bring tht-r plbkl its heutl al-pbsition Whthei' the picker be at the end of the power stroke or at the end of the return stroke. Then, by providing a spring that biases the picker stick so that it tends to move from the end of the power stroke to the end of the return stroke, the force of the spring opposes the force of gravity between the neutral position and the end of the return stroke. In other words, the linkage is so arranged that gravity tends to move the picker toward neutral position from either extreme position whereas the spring tends to move the picker away from the neutral position on the checking part of the return stroke, providing a substantially neutral zone. The same spring force is added to that of gravity in the unchecked part of the stroke, that is, from the end of the power stroke to the neutral position. This facilitates quick return of the picker stick to its shuttlereceiving position after the power stroke.

A further object of my invention resides in providing a compact picker stick and check assembly which may be readily mounted on the extreme end of the rock shaft without interference with the loom parts, this being an accessible position that facilitates adjustment of the checking device.

Still another object resides in provision of a link mounting which permits a certain amount of adjustment to insure that the proper path of the picker is maintained even though variations in the loom construction may require variations in location of one or more of the pivots for the link system.

Further objects reside in providing a link mounting for the picker which is adjustable so that slope or inclination of the picker may be controlled to a certain degree.

A further object of one embodiment of my invention resides in simplification of the parts by causing the checking device to serve the dual purpose of a check device and of a link forming part of the picker stick mounting.

These and other objects will be apparent to one skilled in the art as the following detailed description of the preferred embodiment of my invention proceeds.

In the drawings:

Fig. 1 represents a side elevation of the preferred embodiment of the invention;

Fig. 2 is an end view of the assembly; and

Fig. 3 illustrates the modified form as seen in Figs. 1 and 2.

The loom rock shaft R is mounted for swinging in a loom frame member ii] by means of a bearing i. The sword S supports the lay portion [2 which provides a track for the shuttle in the conventional manner. It is understood that in looms of this type a pair of supports for a picker are provided, the usual and preferred form being a pair of picker sticks mounted oppositely, only one of such sticks being shown in the figures.

The picker stick P is mounted by a link system to be described in detail presently and is connected to a hydraulic check device C. The exact construction of the check device forms no part of this invention, suitable constructions are disclosed in the co-pending applications referred to. Suffice it to say that the check device checks the end of the power stroke which is initiated by power strap i i, whereafter the picker stick returns to the neutral position illustrated in the drawings to thereupon receive the impact of the shuttle. This carries the picker stick to the end of its return stroke with the check device acting to bring the same to a smooth rebound.

The check device is mounted on the end of the rock shaft by means of bracket I5 and is re tained thereon by set screws as at H5. The body i? of the check device houses the working pistons and members I8 are provided for controlling the action of the device. It is noted that with this mounting the adjustments 58 are readily accessible. Arm 2i] is pivoted as at 2! to actuate the pistons in the check device in response to motion of the picker stick. Bracket 88, clamped to the stick by screw 1!, carries ball member 42 which, in turn, connects to arm 23 of the check device by means of member 43. Certain features of the mounting of the check device in connection with the linkage form no part of this invention but are claimed in the patent to Beacon, No. 2,513,907, dated July 4, 1950, assigned to The W eatherhead Company.

The body of the check device is formed to mount cross shaft 22, to which is pivoted a pair of links L acting as guide members for the lower portion of the picker stick. The other ends of the links are pivoted as at 23 to a bracket member 25 mounted on the picker stick so that links L act as guide members for the lower portion of the picker stick. Set screws 25 and clamp plate 2i are provided so that the position of bracket 25 on the picker stick is adjustable. With this mounting, the lower end of the picker stick follows a restrained substantially vertically motion within the limits of its operation.

In order to bias the picker stick toward the neutral position after completion of the power stroke, a spring is provided which reacts against plate 28 clamped to the stick. The lower end of the plate is notched as at 29 and a threaded eye bolt 30 carries adjusting nut 3| which rests in the notch. Spring 32 connects with eye bolt 39 in the picker stick and with a fixed eye bolt 33. The action of this spring will be described in more detail presently.

To complete the mounting of the picker stick, an upper link or arm A is provided. The lower end of the arm is pivoted to ball 52 on bracket 5!], adjustably clamped to the stick by set screws 5 I. The construction and operation of ball joints such as those illustrated is known to all those skilled in the art and accordingly is not elaborated upon.

The upper end of arm A is pivoted to a similar ball member 54 on the upper bracket 55. The bracket is adjustably mounted on a lay portion i2 by means of bolts 58 which extend through slots 51 formed in the fixed mounting plate 56. The picker head 60 has a pocket 6! for reception of the shuttle, and is mounted on the picker support means or picker stick P.

The line xw represents a straight line parallel to the lay, which line is the path traversed by the picker with certain exceptions to be hereinafter noted.

It will be understood, and it can be demonstrated mathematically, that if the pivoted points 56 are located in the line :r:c instead of below it by distance ,1 shown in Fig. l; and if the distances d and e were made equal; and if the lower end of the picker stick were guided perfectly vertically, then the pocket 55 of the picker would traverse a straight line x-m. However, in many looms it is not feasible to mount pivot 54 in the line of picker travel, and provision of a vertical guide for the lower end of the link is an awkward and expensive construction. In the preferred form of my invention I substitute the lower guide members L for the vertical guide slot ofa.thetsclassicazl.-:straight: line .1 motionr Also; inc; certainzloomsit; isrnot 'feasibleyto have the. pivot pointz54 inthe linemen whereas theibracketssu porting the": upper: end: 'of 1the 93/1 1117." is readily. mountedaa distance 1 below the, the line as shown;- 5 With-,gSUCh a mounting; however, ;;the geometry; oft-the systemsrmust be modified to ,producegthe straightilinemotionr. Merelygby-waygof examplege offal-satisfactory arrangement, I have-found that: if the distance cl and: e added itogetherrareg3fl l0 if' stheieifective'lengthof arm-A is 1-115, if the dis--,- tance: dais- 134 /2, and .--;if "the effective lengthnofe link. L is-6:1f, then the-pickertraverses a=path,. which is ideally. adapted f or. the purpose :=at:hands-i,.. Itfiwill .be understoodthat those figures are given .15 merely by way of example and thati-themdomoti limit, the scope of thexinvention in any;way,;,

With; the construction shown in Fig -1,; ,.th;: pocket 6 I travelszinsu-bstantiallya straight line. fromathei neutral positionto the end ofwgthe-re-r' -201 tur-mstroke, that is, to thearightin Fig. ;l. r Ifithis occurs; any slight errori produced by departure fromezthe z classical straight line :linkage rcausedby cexistence. of; the. distance :1 ismsubstantiallygi compensated for by the-action 'ofguidemembers: Lii-whichrdo not guide thewlowerwend in-qa!straight. lineizbecauseof-atheir finite length. However, on thcportionof the stroke' fromneutralposition to the-i-leftinzthefigure, (that: is to the positionr where the shuttle flies :clear: of. the picker), thegaov picker-follows 1arslightly'rising path; The actualv amount-ofvrise'is :very small; but, nevertheless; this lactionetends .to liftwthe tail of the shuttle; whiclrein .turn, urgesthenose down against-the track, and insures that :the: shuttle. does-not fly ;35: up orejumppand yso fail to= traverse the desired path through the shed.

With regard to actionof the spring 32,;.it will. be-rnoted that evenif the -spring;,were omittedp, the-"weight of. the pickenarm Afand guide ,mem.-- 40;- bers 'L, .would urge. the picker'to the neutralposition :from either extreme -position-; because the center of gravity of the assembly is lowestzinthe; neutral position; With this-in mind, -:it .willa-ber readily:;appreciatedSthat the-force-of-the zspringq'f 32-is addedto the forceof gravity in returning thezzpickerwfrom the endof. the :power stroke to the-neutral position. This is desirable because it is important that the picker:-stick--be returned to; its :shuttle-receiving position" before 'the shuttle impact iszreceived'. It will be. furtherfnoted-.tha-t--' themforce Of-spri-ng-VSZ opposes the force of gravity in :the zonebetween-the neutral position and the I1 end of the return strokefithat is; to the rightin-r Fig, 1)? This also is highly desirable-because it 5 afiordsarsubstantially neutralzone during which the? onlyeffective wforces -reaoting ;onthe picker? stick-are those due to the energy, oivtheshuttle and the: resistance of the check device. Thus;; the-:check': device canaccurately beset toabsorbfi the" shuttle energy and bring it'to-a stopwithoutw rebound-V In installing the device; it will; bevobvious'that the-distance ,r isibeyond ,control, itlbeing deter-rmined by the construction iofzgthe loomwv Like-F wise,.-in-;the' interest of;economy,;it;isdesired that-: therarmzA :bemadezofija zstandardrlengthn It is also required thatuthe :zpooket 6 t Then. in zthe:;line.-..*- {IS-{F513; The-latter;conditioneisreadily fulfill-ed b M cause:=thedistance- 12 may be adiusted untilt'thefl picker fis properly:positioned,zby merely loosening the lower clamp 25:,- Bywayof iexample,rif:.idis. tance'j is greater. than standard soqthat; distances e must be increased by-anlequali amduntito bring thespocket: ,6 liwithinzithe :line.txe-xgaicompensae+ tioiri ofsithis-r.@variationxcan xibe :hadzby; "lengthens ingrd by aniamountequal to L LOfthe variation-j, lengths e and It is noted-thatth'e,signipfrthere correction is-.- pqsitive, that; is, :ifgeds 1 lengthened thenzd. is lengthened and vioelversa;

Another-.,.characteristic of; -,the linkage "1811113113111- if. the adjustable bracket: 55 is. installed :I SOQLtha pointofid-r falls inline-withithe pivotsq-23i and-,5 then thepath; a: at {Will ,be substantially parallels-1. toxthealayt; On theother' hand-xii "it isrdesiredj; to-have a slightly; inclined path, the amountran-dii directioneof inclination can;1be controlled ,by-,ad.-;- justing bracket 55 the proper distanceto one side 01--, 'Gh80i3h61;ofgithe neutral-dine; This feature of ,theiinvention; provides: for .zselecting ;the;mosih effective i pathof: the --picker-:w-ithout modification-:1; of the construct-ion of the device.

The. modification shown in- Fig; 3 has a some-1 whats different geometric; arrangement. but in-q eludes manypof the-features of the preferred emf-:- bodimenta. In this modification,- the check device CLQiS-[mDuntBdiOn thegvrockishaft= by meansxof b1"afCket"6{tb'lltE thB check device ,ismechanically, integral-With guidelinks; L1, -pivoted.totthebracketa 60at,,62- i-and..to the :picker stick atfifi:

Location; ofipivotfi? is adjustableas -beiore,a,the.= mountinggincluding; U gbolts 6-? and clamp plate 66? Bolts; 68--;-.may ;:be employed to fasten the check device: to; the: lowerguidej links L1 Members: Tia-end i6 operativelynconnect the check device to. the picker stick. Arm-Aids :pivr oted to the picker stick, by ,means, of bracket-119s: androlarnp' assembly l8.= In this form the geometry is like thatof the classical straight linemo-,-

:tion becausethe upper pivot Point. isin the-paths of) picker travel. Bracket isadjustably mount: ed. by means of slots 8i and bolts 82 and:;has an upper extension tit-that mounts the upper-end of armrAi'; Inthis form'the distances Ad andwe are :made ,equ aI-.. There is, a slight risev near the end;

oils-the, power stroke inthis form also, this, risebeing; caused by guide links 1L1-WhiCh should; theoretically be of infinite lengthto. produce-arr perfectly straight line.-

I'xnay, provide a pair of opposite centering; springs;,i3-inounted:oncthreaded boltflil attached: to ;the :lower bracket-and-adjusted by means'sof, nuts:.-:'l2-.' These springs engage a relatively fixed plate. H attached to the links L1. Theqoperationri of, .-themodified form, is like the preferredlform; except that theicheck device C1,, being mounted; on=.the:guide,-links.Li is inclined during the stroke. ratherthan remaining horizontal;

Of course, it is. understood that I may employ w thenmounting. links shownv'in Fig.7 1 ,with- -the form. ofvcheck device shown in .Fig. 3,, and sub. stitute the springlmounting of Fig. 1 ,1 for @that: i shown-:in'Fig3 without departing irornthespirit ofctheinvention;

It willbeaseen that insiny inventiongthapicker: stick: isiaccuratelygjandpositively guided. ,andthat it :cannot jumpyclear of its support: Also,:it-pro:-; videsza path ideally adapted foreasting theshutr 1318.21. In the; preferred 'formthe;interactioniofp. gravitygand the return spring provides axzone of substantial U neutral equilibrium during the; checkedportionzorthe returnstrolre:

Furthermore, means are providedifor .compengsatinggfor; variationsrrin loom :zconstructionitandzr,

onzadj 1415131113 5 the: inclination; of .the pathi-of: ithe;

tion. Substantial increase in loom speed is possible without spoilage of the fabrics due to erratic casting of the shuttle.

It is contemplated that other straight line motion link assemblies may be employed without departing from the spirit of the invention. The linkage illustrated is one example of a very simple arrangement that accomplishes the desired objects with a minimum number of simple parts. Accordingly, I contemplate that the appended claims and not the illustrated embodiment are determinative of the scope of my invention.

What is claimed is:

1. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker fixed there to, linkage means to mount the picker stick on said assembly so that the picker moves substantially in a straight line in the path of shuttle travel, said linkage means comprising an upper link extending downward from a point in said assembly below the picker and pivoted to the assembly and to said picker stick, and a lower link extending substantially horizontally outwardly from said assembly and pivoted to a lower portion of the picker stick, the lower pivot of said upper link being adjustable along said stick to bring the picker into the desired line of shuttle travel, the pivot of said lower link with said stick being adjustable along said stick to correct the path of the picker in compensation for the displacement of the upper pivot of the upper link from the line of shuttle travel.

2.- In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker fixed thereto, linkage means to mount the picker stick on said assembly, said linkage means comprising an upper link extending downward from said assembly and pinned to the assembly and to said picker stick, guide means carried by said assembly and engaging a lower portion of said picker stick to provide for vertical motion thereof while positively locating said portion of the picker stick in a horizontal direction, said link and guide means cooperating to guide the picker in substantially a straight line path, the center of gravity of said picker and link assembly being lowest when said picker is in an intermediate position whereby gravity tends to urge said picker to said intermediate position, spring means connected to said picker stick to urge the stick toward its outermost position, said spring means being substantially overcome by the effect of gravity on the picker stick and linkage with the stick in an intermediate shuttle-receiving position, means to actuate said picker stick at a point between said links, and a hydraulic check device for absorbing shuttle energy as the picker stick completes its return stroke, said device having relatively movable elements, one element being connected to said loom and the other to said picker stick.

3. In a loom, a frame, rock shaft, and lay assembly, a picker, straight line motion linkage means for guiding said picker, said linkage means comprising a first member to which said picker is attached and a plurality of link members pivoted to said assembly and to said first member to provide substantially a straight line motion for the picker, and a double-acting check device mounted on'one of said plurality of link members and having a pivotal connection with said first member, said plurality of link members acting to positively constrain said picker in its motion whereby reaction of said check device in either direction cannot affect said picker.

4. In a -loom, a frame and rock shaft bearing, a rock shaft, and lay assembly, a picker, straight line motion linkage means for guiding said picker, said linkage means comprising a first member to which said picker is attached and a plurality of link members pivoted to said assembly and to said first member to provide substantially a straight line motion for the picker, and a double-acting check device having a housing element supported on said rock shaft outboard of said bearing, and having an element movable relatively to the housing and provided with a pivotal connection with said first member, said plurality of link members acting to positively constrain said picker in its motion whereby reaction of said check device in either direction cannot affect said picker.

5. In a loom, a frame, rock shaft, and lay assembly comprising a frame, a picker and picker stick, linkage means to mount the picker stick on said assembly so that the picker moves substantially in a straight line, a check device having relatively 'movable elements one element being connected with said. assembly and the other element permanently connected to said picker stick, said linkage means comprising a first link pivoted to said assembly in a horizontal plane through the line of said picker travel and to said picker stick at a distance below said picker equal to the length of the link, and a guide member for a lower portion of the picker stick, said guide member permitting pivoting and vertical motion of said lower portion and positively guiding said portion laterally, whereby the checking force of said checking device cannot in any Way affect the path taken by the picker.

6. In a loom, a frame, rock shaft, and lay assembly comprising a frame, a picker and picker stick, linkage means to mount the picker stick on said assembly so that the picker moves sub stantially in a straight line, a double-acting check device having relatively movable elements one element being connected with said assembly and the other element permanently connected to said picker stick, said linkage means comprising a first link pivoted tosaid assembly in a horizontal plane through the line of said picker travel and to said picker stick at a distance below said picker equal to the length of the link, and a guide member for a lower portion of the picker stick, said guide member permitting pivoting and vertical motion of said lower portion and positively guiding said portion laterally, whereby the checking force of said checking device cannot in any way affect the path taken by the picker.

7. In a loom, a frame, rock shaft, and lay assembly, a picker and picker stick, linkage means to mount the picker stick on said assembly so that the picker moves substantially in a straight line, and a check device having relatively movable elements one element being connected with said assembly and the other element permanently connected to said picker stick, said linkage means comprising a first link pivoted to the assembly in a, horizontal plane through the line of said picker travel and to said picker stick at a distance below said picker equal to the length of the link, and a second link member pivoted to the assembly and to the picker stick, the distance sembly, a picker and picker stick, linkage means sembly in a direction substantially parallel to the path of the picker motion whereby said path may be inclined.

15. In a loom, a frame, rock shaft, and lay assembly comprising a picker stick and a picker, linkage means to mount the picker stick on said assembly so that the picker moves substantially in a straight line, and a check device having relatively movable elements one element being con nected with said assembly and the other element permanently connected to said picker stick, said linkage means comprising a first link having a first pivotal connection with said assembly adjustably positionable in a horizontal plane through the line of said picker travel and a second pivotal connection with said picker stick at a distance below said picker equal to the length or the link, and a second link member having a pivotal connection with said assembly and with a lower portion of the picker stick, said two pivotal connections with the picker stick being spaced by a distance substantially equal to the length of said first link.

16. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker, linkage means to mount the picker stick on said assembly so that the picker moves substantially in a straight line, and a check device having relatively movable elements one element being connected with said assembly and the other element permanently connected to said picker stick, said linkage means comprising a link having a first pivotal connection with said assembly in a horizontal plane through the line of said picker travel and a second pivotal connection with said picker stick at a distance below said picker equal to the length of the link, said second connection having adjustment means whereby said picker may be adjustably positioned independently of said link, a guide member for a lower portion of the picker stick, said guide member permitting pivoting and vertical motion of said lower portion of the picker stick and positively guiding said portion laterally, whereby the checking force of said checking device cannot in any way affect the path taken by the picker, the lower pivot axis of said picker stick being spaced below said second pivotal connection of said link with the picker stick by a distance substantially equal to the length of the link.

17. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker, linkage means to mount the picker stick on said assem bly so that the picker moves substantially-in a straight line, a bracket on said lay assembly mounted for motion substantially parallel to the picker motion, a check device having relatively movable elements one element being connected with said assembly and the other element permanently connected to said picker stick, said linkage means comprising a link pivoted to said adjustable bracket and to said picker stick and a guide member for a lower portion of the picker stick, said guide member permitting pivoting and vertical motion of said lower portion and positively guiding said lower end portion laterally, whereby the checking force of said checkin device cannot in any way affect the path taken by the picker.

18. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker fixed thereto, linkage means to mount the picker stick on said assembly so that the picker moves substantially in a straight line, and a double-acting check device having relatively movable elements one element being connected with said assembly and the other element permanently connected to said picker stick, said linkage means comprising a first link pivoted to said assembly and to said picker stick and a second link pivoted to a lower portion of the picker stick and to said assembly to provide laterally guided vertical motion of the end portion of said picker stick where by the checking force of said checking device cannot in any way affect the path taken by the picker, the pivotal connections of said links to said picker stick having adjustment means whereby the position of the picker may be adjusted independently of said links.

19. In a loom, a frame, rock shaft, and lay assembly, a picker, straight line motion linkage means for guiding said picker, a check device having relatively movable elements one element being connected with said assembly and the other element permanently connected to said linkage, said linkage means comprising picker support means and a plurality of link members pivoted to said assembly and to said picker support means toprovide substantially a straight line motion for the picker, said plurality of link members acting to positively constrain said picker in its motion whereby reaction of said check device in either direction cannot afiect said picker motion, adjustment means between one of said plurality of link members and said assembly to provide for changing the direction of picker travel, and adjustment means between one of said plurality of link members and said picker support means to adjust the position of the picker relative to said link members.

20. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker, linkage means to mount the picker stick on said assembly so that the picker moves substantially in a horizontal straight line, and a check device having relatively movable elements one element being connected with said assembly and the other element permanently connected to said picker stick, said linkage means comprising a first link pivoted to said assembly in a horizontal plane through the line of said picker travel and to said picker stick at a distance below saidpicker equal to the length of the link, a second link member pivoted to said assembly and to the picker stick, the distance between said two pivots on the picker stick also equaling the length of said first link, whereby the picker travels in a straight line and the checking force of said checking device cannot in any way aifect the path taken by the picker, adjustment means to cause inclination of the picker path, and other adjustment means to cause the picker stick to pivot on said second link independent of said first link whereby the neutral position of the picker may be adjusted.

21. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker fixed thereto, linkage means to mount the picker stick on said assembly so that the picker moves substantially in a horizontal straight line, and a double-acting check device having relatively movable elements; one element being connected with said assembly and the other element permanently connected to said picker stick, said linkage means comprising a first link having a pivotal connection to said assembly and to said picker stick and a second link pivoted to a lower portion of the picker stick and to said assembly to provide laterally guided vertical motion of the end portion of said picker stick whereby the checking force of said check 13 ing device cannot in any way affect the path taken by the picker, means to provide for adjustment of the pivotal connection of said first link with said assembly in a direction substantial- 1y parallel to the path of the picker motion whereby said path may be inclined, and adjustment means at the pivotal connection of said first link and picker stick to provide for motion of said picker independent of motion of said link whereby the vertical position of said picker may be adjusted.

22. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker, linkage means to mount the picker stick on said assembly so that the picker moves substantially in a straight line, a check device having relatively 'movable elements one element being connected with said assembly and the other element permanently connected to said picker stick, said linkage means comprising a link pivoted to said assembly in a horizontal plane through the line of said picker travel and to said picker stick at a distance below said picker equal to the length of the link, and a guide member for a lower portion of the picker stick, said guide member permitting pivoting and vertical motion of said lower portion and positively guiding said portion laterally, whereby the checking force of said checking device cannot in any way affect the path taken by the picker, said picker, link pivot points, and the lower end of said picker stick all lying substantially in a straight line vertical to the direction Of picker travel when said checking device is in a vertical position, and spring means to bias said picker stick to said neutral position when displaced therefrom in either direction.

23. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker fixed thereto, linkage means tomount the picker stick on said assembly, said linkage means comprising an upper link extending downward from said assembly and pinned to the assembly and to said picker stick, and a lower link extending substantially horizontally outwardly from said assembly and pinned to said assembly and to a lower portion of the picker stick, said links cooperating to guide the picker in substantially a straight line path, the center of gravity of said picker and link assembly being lowest when said picker is in an intermediate position whereby gravity tends to urge said picker to said intermediate position, spring means connected to said picker stick to urge the stick toward its outermost position, said spring means being substantially overcome by the effect of gravity on the picker stick and linkage with the stick in an intermediate shuttlereceiving position, means to actuate said picker stick at a point between said links, and a hydraulic check device having relatively movable elements, one element being connected to said 14 assembly and the other to said picker stick below said picker stick actuating means.

24. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker fixed thereto, linkage means to mount the picker stick on said assembly, said linkage means comprising an upper link extending downward from said assembly and pivoted to the assembly and to said picker stick, and a lower link extending substantially horizontally outwardly from said assembly and pivoted to said assembly and to a lower portion of the picker stick, said links cooperating to guide the picker substantially in a straight line path, the center of gravity of said picker and link assembly being lowest when said picker is in an intermediate position whereby gravity tends to urge said picker to said intermediate position, means to actuate said picker stick at a point between said links, and a hydraulic check device having relatively movable elements, one element being connected to said assembly and the other to said picker stick below said picker stick actuating means.

25. In a loom, a frame, rock shaft, and lay assembly, a picker stick and a picker fixed thereto, linkage means to mount the picker stick on said assembly, said linkage means comprising an upper link extending downward from said assembly and pinned to the assembly and to said picker stick, and a lower link extending substantially horizontally outwardly from said assembly and pinned'to said assembly and to a lower portion of the picker stick, said links cooperating to guide the picker in a substantially straight line path that rises slightly durin a final portion of the power stroke, said links being arranged that the picker passes through its vertical position on the power stroke, and a hydraulic check device connected between said assembly and picker stick and arranged to check outward motion of said stick as it moves from its vertical position under impact of the shuttle.

GEORGE H. HUF'FER-D.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 454 Dutcher Apr. 21, 1857 97,826 Stone Dec. 11, 1869 860,863 Goodwin July 23, 1907 2,413,629 Hoeber Dec. 31, 1946 2,433,764 Kottemann Dec. 30, 1947 FOREIGN PATENTS Number Country Date 3,124 Great Britain of 1875 7,81 Great Britain of 1885