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Publication numberUS2561255 A
Publication typeGrant
Publication date17 Jul 1951
Filing date21 Jul 1945
Priority date21 Jul 1945
Publication numberUS 2561255 A, US 2561255A, US-A-2561255, US2561255 A, US2561255A
InventorsWerner Buchal, White Zebulon L
Original AssigneeGlenn L Martin Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Automatic feeding device
US 2561255 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

July 17, 1951 2. L. w|-||'r|-: ETAL 2,561,255

AUTOMATIC FEEDING DEVICE Filed July 21, 1945 3 Sheets-Sheet 1 III \II FIG.3 I7 L17 :2 5



- FIG.9

' INVENTOR. ZEBULON L.W|;IITE BY GWERNER BUCl- IAL FIG.IO MAW- A ATTORN EY plurality of our devices are used along a track throughthe overrunning clutch to rewind the Patented July 17, 1951 v UNITED STATES PATENT OFFICE AUTOMATIC FEEDING DEVICE Zebulon L. White, Parkville, and Werner Buchal,

Kingsville, Md., assignors to The Glen L. Martin Company, Middle River, Md., a corporation of Maryland Application July 21, 1945, Serial No. 606,300

3 Claims. (01. 89-33) Our invention relates to an automatic feeding to feed a gun, each feeding device may well opdevice, and particularly to a force feed device crate independently and may be separately adsuch as may be used in the supplying of ammuiusted to supply the amount of force needed at nition to an automatic gun. any given point the driving force of each device It has been recognized for some time that ,5 being limited by the amount of preloading rewhere continuous ammunition feed is employed quired to advance the ammunition to the next to supply a gun located a considerable distance feeding device. 7 from the source, a force feed device is necessary It is obvious that identical or similar problems to help propel ammunition toward the gun. The may be met in any number ofarticle feeding sysdevice of this invention provides an automatic 10 tems and that our invention is equally capable of power driven feeder that can be located at any advantageous use in such systems. point along the ammunition track. This feature It is among the objects of our invention to allows of ready application at feasible points provide a force feeding device for feeding ammualong the track as determined from the engineernition through an ammunition track, or a, like ing viewpoint as to where the greatest load is to supply chute, to an automatic gun, which device be overcome or from the designers viewpoint as consists of a driving shaft arranged to be driven to space allotment. This is possible due to the by an electric motor energized by a torque confact that the booster of our invention requires trolled switch, an overrunning clutch positioned no complicated synchronizing controllin equipto be rotated by the shaft, sprockets arranged to ment but can be installed any place where suitengage the ammunition in the ammunition track able support and a power supply can be provided, and be rotated by the drive shaft operating the unit being self-contained and having an opthrough the overrunning clutch to force the amcrating switch formed as an integral part theremunitio'n toward the gun and yet be free to be of. It is a novel feature of our device that acturotated in the same forward direction by the ation of the energizing switch is controlled by 5 ammunition drawn by the normal pull of the gun. the tension existing on the articles to be moved A further object of our invention is to provide t e immediate point where the booster action a feed control mechanism for use with an autois desired. In this manner our invention promatic gun to which ammunition is fed through vides a mechanism whereby articles such as ama track wherein the demand of the gun for ammunition, or th like, can be maintained ready munition is anticipated by preloading the supply for immediate forward movement at a given preof ammunition in the track toward the gun by determined stress irrespective of the slope at an electric power unit and a drive engaging the which the track is positioned. None of which ammunition, which drive includes a load responnovel features are to be found in the feeding sive switch to energize the power unit when the devices of the prior art. torque of the preloaded ammunition drops in re- When, used in its preferred embodiment as an sponse to gun operation below a certain predeautomatic power driven ammunition feeding determined point and again deenergize th power vice our invention utilizes the power derived unit when a predetermined stress is established from an electric motor to preload ammunition in the preloaded ammunition. along an ammunition track between the feeder 40 A still further object of our invention is to and the gun as controlled by a torque responsive provide an ammunition feeding device for a gun switch arranged as an integral part of the device, that automatically draws ammunition from a whereas formerly it has been customary forthe supply track or chute, said feeding device comgun to overcome the resistance inherent in such prising a shaft driven by an electric motor, ama system sufficiently to pull the ammunition to munition engaging sprockets arranged to be roitself. In the practice of our invention, we have tated through driving springs positioned between discovered a means of urging the ammunition the drive shaft and the sprockets, a torque contoward the gun at a preloaded force in such a trolled switch formed as an'integral part of the manner that the torque on the gun is practically feeding device wherein a contactor is displaced eliminated. In this way, we are enabled to locate from an insulating segment when the sprockets both the ammunition supply and the ammunimove the shaft forwardly through a limiting tion feeding device or devices, at varying disangle of rotative motion so as to completethe tances from the gun without in any way impairelectric circuit to the driving motor whereby it is ing the efficient operation of the gun. When a energized and rotates the drive shaft operating driving springs against the torque of the ammunition engaged by the sprockets to a predetermined tension, at which point the contactor of the torque controlled switch is moved to a position on the insulating block so as to deenergize the driving-motor.

A funtherobject of our invention .is to provide an article feeding system comprising a track and a power unit arranged to impose a predetermined article advancing force upon an article urging it along the track.

Other and further objects of \our invention are apparent from the followingz'description and from the accompanying drawings, wherein:

Figure 1 is a diagrammatic view showing our feeder unit installed in a gun ieedingsystem;

Figure 2 is a side view of our -ieeder unit;

Figure 3 is a sectional View of our feederuinit taken on the line 3-3rof Fig. 2;

:Figure 415.5 a sectional 2Vi6W enlarged to show .:interior construction of .a ;portion of tour fieeder -unit;

' Eigureifa is a :cross sectional view at -.-a 1'educed scale atakenon line ;5--l5 of :Fig. 4 :showing the .sof ra .majchine gun @and supply assembly wherein v acmachine gun 1 receives its ssupplywof ammunimion :from "a track :8 xleading :from an ammuniltion :box 9 =1ocated at some ,point more or less "demote ifrom the gun and past an ammunition feeder unit :l10.

"lllfit includes a motor 5H upositioned Vadfitment a gear :box J2, which houses x-a one-way i583! train l.-2 We arranged :for operation by the motor and (adapted to (rotate (a vshaft -13 in a a given direction. In Figures :4 :and v10 we have "shown a conventional :formrof everrunningclutch such :as :may be used in -our invention- .Here an motor driven worm 42a rotates 1a tgear .-l2b

ithmugh @which passes the :shaft 13. Between sthe ssha'ft' L3 and the gear 4-2-2; isaa iclutch unit .nmnrprising an outertmember 12c {adjacent the {gear Mb, an inner member 12d adjacent .the rah-alt sand provided with ;a 'splural'ity lof spaced pockets, and balls lilie'oarried between the outer and inner members. As shown inJFigure 10 the :acliltch innit "allows' the shaft i3 to freely :rotate in :a clockwise direction, as the ammunition :is .rheingsadvanced by the gun, the balls iZ-e dropmimg into the pockets of the-inner member 12d.

iioweuer, when the motor is energized .to meet 1m increased demand for ammunition so as to a'otate 42a which in turn-rotates gear 12b, the malls :1 2e assume a wedged (driving position \bethe walls of the inner ,andouter members inf :the :clutch unit eprov-id-ing powerized drive or Mnuntedronshatt l3 are two ammunition imipellers 'rarranged as sprockets *IFI spaced apart ,flor spaced-engagement with ammunition oarried in the track 121. 'Spa'ced outwardly of each of the sprockets I! at the ends of the shaft l3 4 are placed discs l4 formed with a series of spaced holes [6a extending therethrough. The discs M are secured to the shaft for rotation therewith by cap screws 15 screwed into the ends of said shaft. Between the discs l4 and sprockets l1 ware :placed connecting springs L6 -coiled around ftheash'aft 13. :Each ofssa'i'd ispr'ings =46 are arranged with its inner end connected to one of i said sprockets and its outer end inserted through one of said holes lBa formed in the discs l4 as slectedto place the spring under sufficient ten- --sion.to1rotate.thessprockets l1 against ammuniition ms hereinafter described.

:Sprcckets :11 have an integral barrel portion Ila formed with 1 a pair of spaced outwardly rextending, "oppositely positioned teeth 11b. A collar IIc'is -adapted to idle on the shaft l3 bettween the barrel portion 11a and the disc i4. At its outer edge the collar is notched to rereeiveraw-lug JAalintegraI with the disc .l4 to v prevent relative .movement between .the collar and .disc. At its .inner .edge the collar 11c is ;provided with a pair of spaced, aoppositely .positioned teeth :l'ldadapted to .interfit between the .teeth Mb -of lthe sprocket Jbarrleportion. Be- .tween leach tooth 11d and -each.ltoo'th H1) .is a space iof a Jew degrees, hereinafter referred 'to as the limiting tangle. I

,T-he sprockets -Iv1 .idle "on the shaft, and the inner end of each spring IIIB "is secured to .the (adjacent sprocket whereby lthe winding of the spring by the motor will1result-in the rotation of the rsprocket.

.The feeder :runitai's mounted on a .hanger 18 secured at its endslias 'lby b'olts L9 xto .a pair. of brackets .20 in Jzurn amounted on the sides (2 I501? the ammunition track -13 to which they :areisecured. i llhe sides 24 .-:are ,parallel .to land slightly spaced (from the hanger 1 8. Illhe sprockets .11 reach rotate in xthe ispace betweenithe changer (and ,.the .-=sides -21 of the track 43; .rtheir teeth .thereby engaging the ammunition .carried by the belt in the track.

The current to the motorris -controlled .by a switching mechanism which is contained in a housing r23 "whichiis disposed inwardly "of-one of the sprockets I?! (see Fig. 5) The mechanism is nonnectedhysuitable .leads -(-not shown) [to the .motor rLl, which is, in turn, connected to any suitable -current V-supply' and includes .a circular .slip ling .25 within and immediately -.adjacent, ibutfinsulated by insulation 35 Jf-rom (the wallwof :the housing 23 and spmck'et lll. Elbe-Sprocket .ll 1 and slip ring 25 are electrically .connected inithe vsupplynincuitnfrnotor H :soa's to 'control the ioperat'ion o'f the latter. Thisoperation is accomplished by :a circuit nlosing m'eans a'd'aptedto electrically connect 'theslip ringite ltheflsprocket wall 1 9 in'turn'iiorms ,part of the circuit to the motor .Tl.l (see.Figur.e -'5) This circuit closing v.means is "provided by the spring 'brus'h I21 :and nontactor 7.8 carried by "the shaft. II 3 .as .part of #the rrotatingvassemblylfi. lTherotating assen'ihlylfis vmounted ion the 48113.11; LL 3 centrally of ilhe slip ring 25 andinsulated' from the shaft vhy bloo'lrs I24 .;and carries :the spring brush i21.,.so that .as the shaft [3 revolves the brush 2'! moves in-contact with the slipvr'ing .25 throughout the entire cycle of the roitatingrmem'ber. The contactorrzfliis also carried by the rotating assembly 26 in contact with the wall .29 of thesprocket whereby the current, received [through the brush 2-1,. is conducted to ground, thereby completing the circuit to the .motor. A non-wconducting' strip is emhedded in the Wall 29 .(see Figs. 5 and 7) for engagement with'the contactor 28 when forward motion of the sprocket l1 ceases due to resistance of the ammunition in the track becoming greater than the torque imposed by the spring. When the forward movement of the sprocket I1 ceases, the teeth I'll; also cease to rotate. The revolving shaft thereby urges the collar He and teeth lid through the limiting angle and toward the teeth llb (see Fig. 6). Thisclosing movement is opposed by the resistance of the now fully loaded spring l6. As the teeth [1d approach within a predetermined distance of the teeth Ilb th contactor 28 is positioned on the non-conductor strip 30 thereby breaking the circuit and deenergizing the motor. As the ammunition i removed by firing of the gun, or a like removal such as when the gun is being unloaded, resistance of the ammunition to being moved in a forwardly direction is decreased allowing sprocket [1, under the urge of spring it in its tensed condition, to rotate in a clockwise direction through the limiting angle of free play between teeth Nb and lld. This relative movement of sprocket I1 is sufficient to move contactor 28 off the non-conductor strip 30 completing the electrical circuit and energizing motor H causing it to rotate shaft IS.

The operation of our invention is as follows: The device is used to transmit ammunition for a machine gun along a track from the ammunition box to the gun. It is a feeder mechanism designed to force the ammunition all or part of the way along the track, thereby helping or elimmating-the need for the gun as a source of am munition advancing force.

This forcing action is supplied by the spring [6, which is kept under a constant tension, through the sprocket I! which is stalled against ammunition solidly packed along the track 8. When the gun 1 begins firing it takes ammunition out of the track 3 and the spring it commences to unwind. As the sprocket begins to turn in response to the spring and as permitted by ammunition use, the contactor 28 is moved off the insulating strip 30, thereby reenergizing the motor; the operation of the motor rotates the shaft 13 to drive sprockets H as long as ammunition can be moved forwardly. 0n stoppage of ammunition movement the motor drive force is sufiicient to overcome the established tension in spring l6 to effect movement of the shaft assembly relative to the stopped sprockets and advance the contactor 28 onto the insulating strip 3!! and thereby disconnect the electrical circuit to motor l.

The spring i6 is constructed and arranged so that it will maintain a constant predetermined tension on the sprocket, which is below that load required to stall the motor. Since the motor, in most circumstances, runs faster than is necessary for the feeding of ammunition it keeps the spring fully wound, and when the gun stops firing, the motor winds the spring completely, thereby operating the switching mechanism to deenergize the motor.

During the firing of the gun the operation of the motor in cooperation with the sprin may in a measure be automatically synchronized to the feed speed of the gun. The construction and arrangement of the springs permits this without excessive stopping and starting of the motor. The energy stored in the spring urges the ammunition along the track. Thi urge if exceeding the demand in turn causes the ammunition belt to bind in the track, thereby loading the motor and reducing its speed to approximately gun speed. The additional friction resulting from the constant accumulation of ammunition in the track for the gun to draw on thus acts to slow down the motor to the gun speed without employment of the switching device. Thus we are able to make constant use of the full torque of the motor, and to apply constant pressure on the ammunition in the track.

In addition to relieving the drag on the gun, our feeder unit reduces the strain on the links of the track by more equally allocating the pressure and tension thereon.

Due to the compact nature of our feeder unit, it may be employed at any position along a track,

. even where a sharp turn in the track is required as when feeding into the gun from below.

When it is desirable, as where the feeder is positioned near the gun, the spring it may be made considerably weaker than that above described so that it will act onl to actuate and deenergize the motor. In this adaptation the sprockets I! would rotate with the shaft is (see Fig. 3). In this way the forward movement of ammunition through the track between the feeder and the gun would be left entirely to the pull of the gun, the feeder unit acting only to pull ammunition from the box to the feeder. Unlike previous feeder units, however, our invention would not leave the control of the motor to the pull of the gun, but would instead control it by the force of the springs In Figure 8 we have diagrammatically shown a modification of our feeder unit in use in an article conveying system capable of handling other types of articles. Here articles 3! are urged along a track 8' by a sprocket l1 rotated in a given direction by a shaft l3 which is actuated by a torque spring l6 which in turn is actuated by a co-axial shaft l3a, the shaft life being driven by a one way gear train housed in gear box l2 which-is operated by a motor I l. The motor is controlled and operated as above described, the switch mechanism being mounted in the switch box 23'.

In Figure 9 we have shown a modified form of mounting of the sprocket whereby a hub 32 is securely fastened by a bolt 33 to the shaft l3, and to which the sprocket I! may be removably secured as by bolts 34. In this way, a sprocket may quickly be transferred from one shaft to another where a change of position or feeding is for any reason required.

It is to be understood that certain changes, alterations, modifications and substitutions can be made without departing from the spirit and scope of the appended claims.

We claim:

1. An ammunition feeder and track for force feeding ammunition toward an automatic gun, comprising, spaced side members for positioning the ammunition, a housing carried by the side members and spaced from the positioned ammunition, a drive shaft mounted in said housing transversely to the side members, irreversible power transmission means for rotating said shaft comprising motor means carried by said housing,

r a worm driven by said motor means, and a worm gear meshing with said worm, an overrunning clutch interposed between said worm gear and said drive shaft, at least one sprocket mounted on said shaft and proportioned to engage said ammunition, said sprocket being limited in angular movement relative to the shaft by spaced abutments carried by said sprocket and shaft, a spring connecting said sprocket and shaft constructed and arranged as to urge said sprocket forwardly a few degrees only to effect displacemerit between said sprocket and said shaft as limited by said abutments; a rotaryswitch mechanism mounted adjacent said sprocket having a contact member carried'by said shaft and radially placed relative to said shaft and adapted: for movement awa from an insulating member mounted on said sprocket, upon initial movement of ammunition in the track toward said. gun,to energiz said motor means upon displacement between the sprocket and shaft to actuate the sprockets for movement of the ammunition in said given direction u-pon initial withdrawal ofammunition from the track by the gun.

2. A booster mechanism for controllingthe feed of ammunition in a track to an automatic g uncomprising, a track section having spaced sides for positioning ammunition, a housing mounted adjacent said track section, a drive shaft carried by said housing with ends offs'aid shaft extending therefrom, anirreversible mo.- tor drive mechanism associated with said shaft and constructed and arranged to rotate said shaft in one direction, an overrunning'clutch interposed between said motor drive mechanism and said shaft, 'sprocketsrotatably. mountedron said drive shaft for independently spaced en,- gagement With the ammunition, at least one of said sprockets being formed with a. spaced: abut.- ment adjacent the shaft, said shaft being: provided with a corresponding abutment arranged for engagement with the sprocket abutment to provide for limited rotative movement a few degrees only between said sprocket and drive shaft, spring means constructed and arranged to urge said sprocket to rotate in advance of said drive shaft, switch means comprising contacts carried by said shaft and said sprocket so arranged to energize the motor upon movement of said sprocket in advance of said drive shaft and to deenergize the motor upon movement of the shaft abutment toward engagementwith the sprocket abutment, upon stoppage of said sprocket by the ammunition stopping in said track when the gun stops firing.

3. .A feeder mechanism forforcing the movement of articles in an article advancing system comprising, an article positioning means arranged to expose a portion of said articles carried thereby for advancement in a given direction, a shaft spaced from the article positioning means, article impelling means mounted onsaid shaft adjacent the article positioning means and arranged for rotative engagement with said articles, an irreversible motorized drive means drivingly connected to said shaft, said drive means having motor disengaging means 'a'ssociated therewith to accommodate free forward.- 1y rotation of the shaft relative to the drive means, spring means between the shaft and impeller so constructed and arranged to forwardly rotate the impeller relative to the shaft. abutment means carried by said impelling. means and shaft limiting the relative movement therebetween, and switch means between said impelling means and said shaft responsive torelati-ve movement therebetween to energize and deenergize the motor of said drive means.


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

UNITED STATES PATENTS Number Name Date 1,714,105 Ramsdell May 21, 1929 2,382,522 Trotter Aug. 14, 1945 2,390,401 Trotter Dec. 4, 1945 2,390,477 Trotter Dec. 4, 1945 FOREIGN PATENTS Number Country Date 590,426 France June 17, 1930 558,949 Great Britain Jan; 28, 1944 558,950 Great Britain Jan. 28, 1944

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US2382522 *17 Jun 194214 Aug 1945Bell Aircraft CorpOrdnance
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2629287 *10 Jan 194824 Feb 1953Hughes Tool CoAntirollback brake for ammunition boosters
US2873649 *9 Dec 195517 Feb 1959Brevets Aero MecaniquesFeed devices for automatic guns supplied with ammunition in the from of a cartridge belt
US2973691 *28 Feb 19507 Mar 1961Herbert GoldsmithMissile launcher
US3328963 *27 Dec 19624 Jul 1967Curtiss Wright CorpAttitude control device for space vehicles
US4572052 *5 May 198325 Feb 1986The United States Of America As Represented By The Secretary Of The ArmyDeclipper/feeder
U.S. Classification89/33.5, 192/127, 200/61.58R
International ClassificationF41A9/00, F41A9/51
Cooperative ClassificationF41A9/51
European ClassificationF41A9/51