US2477264A - Flexible feed chute - Google Patents

Description

July 25 w49 c. B. PEARsoN -E-r AL 2,4??24 FLEXIBLE FEED CHUTE Filed May l5, 1944 v .5 Sheets-Sheet l y @weer SANDTeOA/l Foe THE FEM Hrroen/e'w July 26, 1949. c. B. PEARsoN ET Al.

FLEXIBLE FEED CHUTE 3 Sheets-Shaml 2 Filed May 13, 1944 FORME/WM July 26, 1949.

cfs. PEARsoN -ET AL FLEXIBLE FEED CHUTE 3 Sheets-Sheet 5 Filed May 13, 1944 cf Fm Fof? TH HRM /Troe/EYS Patented July 26, 1949 UNITED STATS A'rsr FLEXIBLE FEED CHUTE poration of Delaware Application May 13, 1944, Serial No. 535,476 i Claims. (Cl. 193-25) Our invention relates to a exible or expansible structure for guiding the movement of a flexible member. More particularly, the invention relates to a nexible feed chute for ammunition belts and the like, and will be described in this connection.

In general, the structure may act as a conduit, chute, conveyor, duct, or the like for guiding a flexible member. The term exible member is used in this specification in a broad sense, comprehending a unitary or articulated member or merely a series of adjoining articles, Whether or not they are interconnected.

'I'he invention finds particular utility in the guidance of an ammunition belt in its movement from an ammunition box to an automatic gun, such as a machine gun or cannon, particularly where the automatic gun is mounted for universal movement, although the invention is also very useful with fixed-mount automatic guns. The general problem in this art is to guide the ammunition belt to the gun While preventing kinking or undue bending of the belt and,A at the same time, to feed the ammunition into the gun at a proper angle.

When applied as a feed chute for an automatic gun, the invention includes among its objects the provision of an improved feed chute which will flex in various directions in response to forces of lovv magnitude so as not to interfere with the manipulation of the gun; the provision of an improved feed chute which is limited in its bending so that the ammunition belt guided thereby will not bind, jam, or become bent in a radius or through an angle shorter than that for Which the ammunition belt was designed; the provision of an improved chute of extremely sturdy and long-Wearing construction in which, if desired, the ammunition belt can be moved in either direction without danger of binding, jamming, or marring any portionY of the cartridges or the structure interconnecting same; the provision of an articulated feed chute formed of a plurality of assembled identical units; the provision of an improved articulated chute in Which any damaged or Worn unit can be removed and replaced without disjoining all units of the series; the provision of an improved chute exposing, and making accessible throughout its length, a portion of the ammunition belt to facilitate inspection thereof and immediate correction of any diiculty that may arise at any section of the chute as the ammunition belt passes therealong; and the provision of a chute shaped to the ammunition to provide small clearances, thus avoiding any jamming of the ammunition or any piling up thereof when an ammunition booster is employed.

It is also an object of the present invention to provide a flexible structure for various other purposes and having some or all of the attributes mentioned in the preceding paragraph.

It is a further object of the invention to provide a novel transverse unit which may be assembled and disassembled With identical units to form a passage, and to provide a novel interconnecting means for expansibly interconnecting adjacent transverse units.

Still a further object of the invention lies in the making of such a transverse unit by employment of a Wire frame and one or more attachment members, all comprising a frame structure forming a part of the transverse unit. The invention also comprehends a novel means for securing the attachment member to the frame.

It is also an object of the invention to provide a transverse umt including at least one guide member Which cooperates with the guide members of adjacent transverse units in providing the conveying passage and forming guide Walls for guiding the movement of the flexible member along such passage.

The flexible member moves along the passage in frictional relationship with the guide members, and it is desirable to reduce the frctional forces so that the flexible member can be drawn through the chute by application of a minimum force. In this connection, it is an object of the present invention to provide guide members having a limited frictional contact With the exible member. In its preferred embodiment, the invention comprehends guide members providing lands of limited dimension transverse to the passage for guiding the flexible member. It is also an object of the invention to provide a cavity beneath such lands for the means interconnecting the transverse units of the chute.

Further objects and advantages of the invention Will be evident to those skilled in the art from the following description of an exemplary embodiment as applied to the problem of guiding an ammunition belt in its movement to a machine gun.

Referring to the drawings:

Figure 1 is an elevation of a machine gun viewed from the rear and supplied With ammunition through the chute of the invention;

Figure 2 is a plan view of the expanded chute, with sections broken away;

Figure 3 is a fragmentary plan view indicating how the chute may be flexed longitudinally in the plane thereof;

Figure 4 is a similar fragmentary plan View showing how the chute may be contracted or compressed longitudinally;

Figure 5.151@ transverse ,section ofi: the chute, taken as indicated tl'ieline 5-15 o f Figure Figure 6 is a fragmentary sectional View, taken along the line S--B of Figure 2; and

Figures? to 11 represent elements used and 010W Referring particularly to Figure '7, the foundasteps employed in the making of the cn'pltelf transverse unit (shown in Fiuijedllikfigure being a perspective View of thewlre i 8 being a perspective viewgjf` A angnattacl'hrln'ent'' frame structure consisting of tigev framewasseinf bled with two attachment merifibe'rs;A being a perspective View of a guide member ,and Figure 11 showing the complete transverse unit withftw guide members assembled in the frame struc il .Ml.,v im', nm A The drawings show a'fed chute of t tion, lgenerallydesignated l; b t for?? Shaped .arlegdmsiqned to, mined degree of fleXure in all directie Y Y :l

mit trusting @assuming afin@ @rimani Y Pelt,

feiner 10eil1ff=i`ui.r..edA tefgilgwrtheimovsm nt of heg C? ev degree iii/111 l cause un'tiori `loeltto bind,-`

011: :tendria .Celtiav thaamm jara. Seperateeorbe Ornepermanentlydeformed?,

TQ tehuis, 455.gif gthelinventioasisdesigned to` Draven?, beadingberend)such-permissible degree-` and; to. guide@ ammunition ,belttozthe sun eitlfi xglusivel Lloyforcelsi impertf-:d to the belt byltherguneer, as.. slknswnin the arnbyern-.f ployment 0f suitableboesters Ing-eitlfienevent,H itisvey desirable-.theek ,l ueitonibeltmev thx e Chute'witha minimum of. frictional.

r:preis/,ities:A for. e

HT einem@ istanti@ frietiorial contact b-tween .thez am;

l1,1 i* *.belt-',it and the chute I5, as willV be hereinafter described.

formed b beriguiding p-assageiiDeS" WHA Figur-e5() guiding the moi/@isset di die aiinumuiibelt tioi'l'slilton of each transverse unit comprises 2o he th-f?treererseslements@par stvl i @eran renti E21,Y

et, exten ding, een fallu it pre ents .the sa ruim dva lineup and;

y need along;

nl :mi l: n! n ,I y -1 55 lmp@ hef-Pans. foi par 1.,@ transmise elements vh. Within each 65 disp,

t .Slriraferablypro- Vlellsaff. lieliinglzthe ,two adjacent trans-. verseiunitsgwtogether inl anexpansible and 75 flexible mannen Y ach attachment member 43 is formed of thin sheet metal punched and bent to be of general U-shape, as shown in Figure 8. For example, each attachment memberY 43 includes a side section 44 :forming the base of the U and adapted Vto engage a pair of the side sections 38 of the frame 33. Each attachment member 43 also includes tWo arm sections 45 extending substantially at right angles to the side section 44 and extending, respectively, in contact with pairs of the face sections 36 and pairs of the base sections 40 of the frame 33. The side section 44 provides at one end two outwardly-extending tabs 41 adapted to be bent around the Wire forming the adjacent side section 38 in a manner best shown in Figure 9. The sheet metal material originally present in the zone between the tabs 41 is bent inwardly to form a hook tab 48 which ultimately is again bent to form a .hook 4S, the main portion of which extends generally parallel to, but spaced a slight distance from, the inner surface of the side section 44. The side section 44 provides at its other end a single tab 50 bent outward, as shown in Figure 8. This tab is subsequently bent additionally to encircle the adjacent side section 3B of the frame 33, as best shown in Figure 9.

The side section 44 also provides an extension comprising a link I. This link is preferably peripherally-continuous and provides an end bar and two arms defining an opening 52 of sufficient width to receive a hook 49 of an adjacent transverse unit 3D in a manner to be subsequently described. In addition, the side section 44 provides a circular opening 53 disposed opposite the hook 49 and in such position that the extreme end of the hook 49 substantially bisects the opening.

In a similar manner, each arm section 45 provides tabs 41 and 50' adapted to be bent to encircle the adjacent wire of the frame 33. However, in this instance, three tabs 5U are ernployed and the end 42 of the Wire of the frame 33 is preferably positioned to be covered by one of the tabs 5D'. Likewise, each arm section 45 provides a hook tab 48 which is subsequently bent to form hook 49 (Figure 9) and each of the arm sections 45 also provides a link 5l', similar to the link 5l previously described, as Well as an opening 53'.

It will be apparent that two attachment members 43 are assembled to the frame 33 in opposite side portions thereof to form a frame structure, shown in perspective in Figure 9 and indicated generally by the numeral 55. It will be apparent, also, that the two attachment members are of slightly different size to compensate for the difference in height of the passage 3l on opposite sides thereof; otherwise, the two attachment members are substantially identical. Also, it will be noted that all of the links 5| and 5l' extend in the same direction from the frame 33. These links can lie substantially in the plane of the particular section (44, 45, 45) from which they extend but it is sometimes preferable to offset inwardly in slight measure the link 5I, as suggested in Figure 8, though this is not in all instances necessary. Likewise, the links 5I' may be slightly oiset inwardly, if desired.

The frame structure shown in Figure 9 is next assembled with two guide members of the type shown in Figure to form the transverse unit 30 Vshown in Figure 11. Referring particularly to Figure 10, the guide member is indicated generally by the numeral 60 and is substantially U-shaped. It/provides a side wall 6| disposed to I respective arm sections 45 of the adjacent attachment member. Each cross wall 52 provides attachment portions 64 in general alignment with each other and adapted to be secured to the adjacent arm section 45 of the corresponding attachment member 43, as by spot welding atpoints 65 of Figure 1l. Between these attachment portions 64, each cross wall 62 is deformed inward to provide a land 61 to leave a cavity 68 beneath the land 61, this cavity being bounded on one side by the adjacent arm section 45 of the corresponding attachment member 43, the'adl jacent hook 49 being within this cavity. The

land S1 may taper or curve slightly with respectv to the longitudinal axis of the passage 3| which it bounds, so that the entry portion of each cavity 30 is of slightly less width than the hookbounding portion. Such slight taper or bending is apparent from Figure 10 and aids also in maintaining a smooth articulated wall when the finished chute is flexed as in Figure 1. Each land 61 forms the base of a tongue-like extension 10 substantially flush with the land and which projects along the adjacent link 5I in covering relationship.

The guide member 60 is preferably so secured to the adjacent attachment member 43 that the side wall 6l is spaced a slight distance from the inner surface of the Side section 44 of the attachment member 43. A space or cavity 13 is thus provided, shown somewhat exaggerated in size in Figure 5 for purpose of clarity. In this cavity is'pcsitioned the hook 49 of the adjacent j side section 44 of the attachment member 43.

It will thus be apparent that each transverse unit 3U provides a plurality of links 5|, 5I', as well as a plurality of link-receiving means comprising the hooks 49,` 49', the link-receiving means being respectively positioned in cavities of the transverse unit. It will be apparent, also, that another transverse unit can be stacked on top of the unit shown in Figure 11 in such way that the links and tongue-like extensions of the guide member will simultaneously enter such cavities, usually after slight inward exure of the link-extension structures to align same with the cavities. For example, the link 5I and its adjacent extension 12 of the guide member 30 can be guided to enter the cavity 13 simultaneously. In like manner, each link 5l and its adjacent extension 1D of the guide member can be guided to enter simultaneously a corresponding cavity 68 beneath a land 61.

As each link enters its corresponding cavity, it passes between the inner face of the hook in this cavity and the adjacent face of the land. The available space for entry of such link and its adjacent extension of the guide member may substantially equal the thickness of the composite link-and-extension structure, or this structure may enter the cavity only by slight and temporary bending of that edge of the land shown lowermost in Figure 10. In any event, as the link-extension structure moves into the cavity, the end bar of the link passes the hook and the link springs outward into resilient engagement with the inner surface of the attachment member providing this hook. In this posichute without danger of injuring the cartridge or the chute.

Any desirable means may be employed for attaching the opposite ends of the chute respectively to the gun I1 and the ammunition box (not shown). In Figures 1, 2, and 6, one form of quick-release attachment means is shown, including a generally U-shaped terminal member 80. This terminal member provides a lower or bridge section 8| generally channel-shaped in vertical cross section to provide depending walls 82 and 83, the latter being extended downward below the former, as best shown in Figure 6,'l

and being surrounded by a stiffener 84 welded thereto to form a composite wall. Extending toward the gun from the depending wall 82 are two projections 85 (Figure 2) perforated to receive rod 86 extensible through lugs 81 forming a part of the structure of the gun and serving as a means for attaching the terminal member 80 to the gun. At each side of the passage 3| of the chute, the terminal member 80 provides upwardly-extending, channel-shaped end members 90 providing side walls 9| bent inward at theirextreme upper ends to form a guide channel 93, best shown in Figure 1 and in the upper portion of Figure 2. Vertically movable in each guide channel is a locking member 94 bent outward at its upper end to form a handle or operating portion 95. As best shown in Figure 1, the lower portion of each locking member is split longitudinally by a channel 96 enlarged at 91 and 98 to provide circular openings with side walls resiliently embracing the shank of a rivet 99 extending out- Ward from a portion of the terminal member 80. The channel 96 extends upward to the larger end of a buttonhole-shaped opening for a purpose to be described, and the relationship between the shank of the rivet 99 and the locking member 94 is such that this rivet shank is resiliently retained either in the opening 91 or 98, depending upon whether the locking means is in an upper or lower position (the latter being shown in Figure 1). The width of the channel 96 is slightly less than the diameter of the rivet shank so that the bifurcations at the bottom of the locking member spread slightly as the locking member is moved from one extreme Iposition to another. By this means, the locking member is retained in its upper or lower position without danger of change in position due to vibration, etc. The ammunition chute itself provides means detachably connected to the terminal member 80. As best shown in Figures 1, 2, and 6, the endmost transverse unit of the assembled chute has connected thereto two generally U-shaped end members |05 beaded to correspond to the periphery of the endmost transverse unit, these end members encompassing the two attachment members 43 of the endmost transverse unit and being suitably welded thereto. Each end member |05 provides a, tongue |06 extending along and welded to a tongue |01 forming a part of the guide member 60 of the endmost transverse unit but extending toward the gun in a direction opposite to the extension thereof. The tongue structure formed by the welded tongues |06 and |01 carries a rivet |08 (Figure 2) providing an annular groove |09 immediately beneath a rivet head l0. This groove is of sufficient width to accommodate the bottom wall of the adjacent end member 90 and its locking member 94. The larger portion of the buttonhole-shaped opening |00 aligns with a corresponding-sized opening of the bottom wall of the end member when the locking member 94 is in raised position so that the rivet head ||0 can be moved therethrough, after which the locking member 94 is moved to its lower position, s-hown in Figure 1, to bring the smaller end of the buttonhole-shaped opening around the rivet, whereby the walls of the locking member at the sides of this smaller end of the buttonhole-shaped opening move beneath the rivet head H0 to prevent its withdrawal.

Correspondingly, when it is desired to attach the end of the chute to the gun, it is necessary only to place one rivet |08 in position and apply pressure between the sides of the chute to deform same temporarily in sufficient amount to dispose the other rivet within its adjacent end member of the terminal member B0, whereupon release of the chute will Ypermit this rivet to enter the aligned openings of the adjacent locking member 94 and end member 00. Thereafter, each locking member is moved downward to bring the smaller yportions of the buttonhole-shaped openings into encompassing relationship to the rivet. To remove the ammunition chute from the gun, it is necessary only to lift the locking members 94- and apply inward pressure to the sides of the chute to deform same suicient to withdraw one rivet |08 from the aligned openings, after which the other rivet can likewise be withdrawn.

With this type of attachment means, it is desirable that the cartridges and projectiles be guided laterally during their movement from the last transverse unit 30 across the terminal member S0. For this purpose; the guide member 60 of the last transverse unit provides upper and lower tongue members |20 and |2| forming continuations of the lands 61 but extending toward the gun a sufficient distance to guide the cartridges across the terminal member 90. It will be understood that the quick-release attachment means disclosed can be appropriately modified to adapt it to various guns; also, that similar quick` attachment means can be provided at the other end of the lchute where it is joined to the ammunition box, whereby the entire chute can be attached and removed quickly without employment of special tools.

Various modifications and changes can be made in the invention, and the invention can be adapted to various uses apparent to those skilled in the art, without departing from the spirit of the appended claims.

We claim as our invention:

1. In combination in a flexible passage means for guiding the movement of a flexible member: a plurality of transverse elements each shaped to determine the generalv cross-sectional coniiguration of a member-guiding passage; means for expansibly linking said transverse elements for limited movement toward and away from each other; and a plurality of guide members respectively retained by said transverse elements at positions along said passage, each guide member providing a cross wall within the corresponding transverse element, each cross wall compris# ing an attachment portion having a face bounding an adjacent part of said passage and a land having a crest surface disposed inwardly of said passage from said face and bounding another part of said passage, each guide member including also a tongue-like extension projecting from said land in a direction longitudinally of said passage and substantially flush with the crest surface of said land, each tongue-like extension being ,of sufficient length to overlap the land of ,germana 11 an adjacent transverse element, ztheelands and their tongue-like `extensions forming `:an -fartculated rail -to guide said flexible .member as fit moves along isaid .fpa-ssage yriddim-iep same spaced *from the attachment portions ofisaidzguideimembers. Y

J2. A-A :combination :as defined claim 1, in 'which :ea-ch ofsaid lands provides a cavityltherebeneath Iand in Ywhich feachpfisaid tongueelike extensions slidably projects :into thercavityiof A:an adjacent guide member.

:3.,52Ina flexible-articulated Ychute providing ia Ymember-guiding ,passage for rguiding lthevmovement tof .a exible memben the combination fof: -a plurality :of :interconnected Aframe vstructures eachwextending vsubstantially transversely with respectfto said ypassage :and each'providing a Wire frame shaped `to determine the Lgenera-l cross-sectional configuration of said 4memberguiding passage, and each frame structureggproviding -an attachment: member connected r:to fthe wire rtrame, each attachment member :providing aflink and Aa link-receivingrmeans, the link 'of each attachment -member extending :beyondsaid .Wirefframe a :suflicient distance to :slidablyren- ,etage `the 1attachment :member .of an adjacent .fr-ame :structureland to lock -with 'the'slink-'receiving-.fmeans-of -such adjacent frame structure gto permit 'limited `movement of .adjacent -frame structures toward :and away from each-other; and a guide :member fixed to each attachment member and VVproviding sa tongue-like extension adjacent Isaid :link .and extending into overlapping Irelationship withwthe'pguide :member 'of an adjacent framestructure to fformz-anaiticu-lated .wall for said passage.

4. yA combinatiomas denedrinac'laim 3-in which said guide-*member comprises a thin :flexible Aplate providing spaced Aattachment portions-'secured to .said attachment member and deformed inw-ard .at a `position between Asaid attachment portions to -form ra member-eontactingrland and .toform Aa cavity dimensioned to slidably 1receive Vrboth Aa link of an adjacent iframe zstructure 'and the tongue-like extension adjacent @such link, :said

tongue-like lextension :forming fa f flush continuation of said land.

5. In combination in a-transverse -unit :adapted for assembly -with identical @units to'fform :a noxible articulated chute :providing :member-'guidinsr passage: a Wire frame providing base, side, and face sections bent to determine V:the general cross-sectional conguration `'of :the 4member- ,guiding passage; fagpair of lsubstantially :U -shaped attachment members Within said wire-frame adj-acentfsaid-side sect-ionsand -providing'za mlurality ofrbentxtabs krat` least partially encompassingrsaid :Wire -frame tofretainxsaid attachment Vmembers ;to .said Yframe; Va-'plurality of vlinks extending from .each attachment -member in 'a rdirection g-away from-said frame, each transversennitproviding a rplurality of cavities 'for slida-blyfreceivingsaid plurality @of links of .an adjacent transversennit; means i'for :limiting the movement of such 'links in Atheir respective :cavities ofxan fadjacenttransverse :unit 'and guide members within randisecnred to lsaid .attachment members 7and fzproviding a .plurality'of tongue-like extensions respectively extending along said links la sufiicient distance lto overlap the guide rvmember (of an 'adiacen't transverse unit-When 'assembled fthereto, whereby Athe guide members vand A'the :extensions v'of adja- V4cent transverse units cooperate in providing an articulated *lining for fsaid passage.

6. VIn a fiexible articulated chute providing Va member-guidingspamage: forguiding mwement of a flexible member, the combinationfofr: .a fplmgality :of transwer-se :elements aeach 1 shaped .to a determine :the iegeneral foresee-Sectional mon- ;tguration. :of 'the member-guiding passagexeach Itransverse element providing a :'pluraiitymf iter- -Wardly-"facmg :cavities disposed sinzfspa-eednzela- `tionshp .around the "periphery aof-:saidz passage; means :Eorzexpansiblylinking said :transverse eiements-ftogetheriorlimitedlnovementatewardand .away zfrom eeachfrather,` said 'Imeans zincludingffa plurality gofiehooks irrespectivly Y disposed .in Ssai'd cavities/fand openingfrearwardlytherein andlfa eorrespondmg :number l"of links #extending @rear- Wardlyifromueach"transversewelemwt to project slidably "-iinto i'the' `respective rcavities 'fo'f'ithe fimmedi'ateily vadjacent `:transverse lelement ito 'tink with the hoks 4therein Y fand VJmaximize the 4separation Lof fadjacenttransverse ielements; and ea pluralityof guide members 'respectively secured within said transverse elements, 'each guide men'iber l including' fa "tongueli-ke extension *proljecting vereartvardly lfrom *the "transverse v'element to which '-`it "is -se'cured and "inA covering relationship with -'acorrespondingink 'off this *transverse element, Ieach tongue-*like kextension projec'ting siidably finto fthe same cavity of the v-'adjacent transverse =elemen't'-asthelmkit covers whereby the "tongue-iI-ike extensions "remain in their respective fcavitiesirrespective Volf bending of "said chdte'to; prevent tiieerds ofsa'i'd extensions from projecting "into 'saidaneniber-guiding passage to interfere with movement df:sad"`i'lexibie'member therealonggsaidguide'members and ltheir tonguelike extensions .forming rartict'ilateli lining -walls of' said "passage Vand said tortguelke extensions bridging "between adjacent transverse elements With"the ends 'of the vextensions 'Still Yldisposed Vlin their respective cavities even When'said'hooks'engage `said "links to maximize the separation .o adjacenttransverse elements.

7. -In Aa flexible anununtionchuteor. conductindgi'to a mah'ine gun'through.devionspaths an ammunition beltcompri'sing a,plura`lityl.of Linterconnected cartridges, each natridge-nomprising cylindrical shell .casing and -a :projectile v.of smaller Lexternal diameter v.than-.abase portion of sai'dshll casing, the combination of: lauplurality of `transvr-:rse elements disposed `side by r side to determinetheross-sectional .conJiguration-.of-ian ammunition-guiding Y-joassaga each transverse element .in-cludi11g=on 1 eaohfside-of -the x.mid .piane thereof -ai-base section, a facer-.section and a side sectionvspacing said ibase dand face-.sections drum each other, theiside section vonl one iside-of `said passage Ebeing longer than the @side section lon the other side sof vsaid message #to rspace :therbase and :face :sections on r-said 1m-e side a isuiicient distance to contact-fand :fconduct :said i cylindrical shell -aca-sings :and to space the ibase *and face sections .on vfsaid :other vside .fa flesser diistzmce :ibut

suicientto :contadtrand saidfcartridg'es; means for expansiblyrlinkingssaid rtransverse-'ilements together iat a :plurality of 'positions fdisposed periinheradly mr said passage for limited mnvement 'of :adjacent 'transverse elements Itofand :away ifrom 'Teach 1 other Iat f'such :peripheral :positions ,and 2a ipluralityi'of guide A-menribers respectively Ysecured "to ksaid itransverse 'element-s, each `guide meniber having "tongue-'like extensions fextendirrg -in overiappinjg 'relationship Ewith the guide member offanadjacertftransverselement to cooperate therewith in )providing an articulated `llining Tsaid ammunition-'guiding 1 1% passage to guide said cartridges in their move- UNITED STATES PATENTS ment toward said gun. CHARLES B. PEARSON. Number Name Date GEORGE R SANDSTRCM 2,310,884 Tlevaskis Feb. 9, 1943 s 2,419,315 Elliott Apr. 22, 1947 REFERENCES CITED The following referenloes are of record in the fue of this patent:

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