US2480950A - Cartridge belt link - Google Patents

Description

p 1949, J. J., MURPHY 2,480,950

CARTRIDGE BELT LINK v Filed July 14, 1945 2 Sheets-Sheet 1 S p 1949. J; J. MURPHY CARTRIDGE BELT LINK v 2 Sheets-Sheet 2 Filed July 14, 1945 Patented Sept. 6, 1949 UNITED STATES ATENT OFFICE CARTRIDGE BELT LINK Application July 14, 1945, Serial No. 605,079

3 Claims.

This invention relates to metallic cartridge belt links, more particularly to metallic cartridge belt links which are interlinked and hinged together by the cartridges received in the links to form a belt of ammunition and it is an object of the invention to provide an improved cartridge belt link of the character indicated.

The universal character of the movements of a rapid fire gun during operation from both relatively fixed and rapidly moving gun mounts and the necessity for an ammunition belt havin the required attributes of flexibility in order to satisfactorily operate in the gun are well recognized. Likewise, it is known that the limitations of space around a gun are such that annnunition belts must be stored in awkard but relatively accessible places not always convenient to the gun, thereby making it necessary that the ammunition belt be capable of additional twists and turns. A cartridge belt link fulfilling the necessary requirements as to flexibility when assembled into an ammunition belt is described and claimed in a co-pending patent application Serial No. 469,679 filed December 21, 1942 in the name of Roy S. Sanford and entitled Cartridge belt link, and issued on December 4, 1945 into Patent No. 2,390,331, which patent is assigned to the same assignee as the present invention. The cartridge belt link of the said Sanford application comprises two cartridge-receiving members connected by a universal joint which permits thecartridgereceiving members to move relative to each other as the ammunition belt twists and turns during use. With universal joints between the links holding the rounds of ammunition and because the rounds are mounted in the links substantially at their centers of gravity, the jerks and movements imparted to the ammunition belt by the short jerking movements of the gun feeding mechanism and the additional jerking move ments caused by rapidly moving the gun from one position to another, may give rise to a tendency for the rounds to flop indiscriminately from one position to another out of line and to remain out of line. Accordingly, it is a further object of the invention to provide an improved cartridge belt link of the character indicated having a restrained swivel or joint by virtue of which the relative movement between the members of the link brings into operation a force tending to restrain the relative movement.

It is a further object of the invention to provide an improved cartridge belt link of the character indicated in which a, force is brought into operation by the relative movement of the link members from a normal position to return the link members to a normal position relative to each other after displacement therefrom.

Ammunition belts having a, large number of rounds are heavy and consequently the feeding mechanism of a gun must exert a strong pull to feed the ammunition. The ammunition in its pathway to the gun passes around feed and uide rollers and through guide chutes which necessitate that the rounds twist and turn to some degree, and it is apparent that such twists and turns must be made with as little resistance as possible in order not to increase unduly the load on the gun feeding mechanism. Accordingly, it is a further object of the invention to provide an improved cartridge belt link of the character indicated in which the force restraining the movement of the members of the link relative to each other is initially small and increases as the amount of the relative movement increases.

The sharp quick jerks of the gun feeding mechanism are imparted to the whole ammunition belt and consequently accelerate the ammunition belt with the same short jerking movement. This not only places a heavy shock or acceleration load on the gun feeding mechanism, but it places a heavy strain on the cartridge belt links immediately adjacent the gun which bear the total force exerted in moving the ammunition belt. Accordingly, it is a further ob-' ject of the invention to provide an improved cartridge belt link of the character indicated in which there is relative movement between the link members in the direction of feeding and the relative movement is resiliently restrained so as to provide a shock absorbing effect.

In carrying out the invention in one form, a cartridge belt link is provided having two cartridge-receiving members which are joined to each other with a universal joint and have a normal position and a limited degree of movement relative to each other. One of the cartridge-receiving members comprises a pair of axially spaced cartridge-receiving elements with an integral bridging member connecting the elements, the bridging member including a centrally disposed aperture and a pair of spaced guides defining the edges of the aperture. The second cartridge-receiving member comprises a resilient single cartridge-receiving element having a pair of tongues extending therefrom through the centrally disposed aperture and terminating in a pair of laterally projecting lugs which engage the bridging member to connect the two members of the links. The pair of tongues extend anguand the other end is provided with a tongue 3| fitting thereinto, the ends tapering away from the cutout portion and the tongue. While the cross section of the element 13 may be of any desired shape, it is shown as being circular to facilitate the insertion of the cartridges.

The cartridge-receiving member l2 comprises a single split loop or element substantially circular in form and is somewhat larger in diameter than the diameter of the cartridge received thereby so that the loop may contract during certain of its functions and in order that the cartridge may fit loosely in the loop as shown by the broken line 9 in Fig. 4 to permit the links to pivot readily about the cartridges and facilitate bending around feed and guide rollers. Referring to Figs. 2 and 4, the loop I2 is seen to be in the form of a split ring having two parts 36 and 31' spaced apart by a slot 38 which extends substantially around the loop. The loop I2 is open at one side thereof providing two ends, each terminating in a narrow integrally formed tongue 34. The tongues 34 extend upwardly from the ends of the loop and terminate in the lugs 35 which extend laterally from the tongues, the lugs extending through the aperture 23 and serving to connect the element l2 to the bridging member Hi to join the link members together. The tongues 34 are substantially rectangular in cross section, thereby providing flat surfaces facing the curved edges 23 and 24 in the assembled condition, and are bent at an angle to the ends of the loop l2 to extend angularly outward from their junction therewith so that the outermost ends of the tongues from which the lugs 35 project are spaced a greater distance apart than the innermost ends of the tongues which join with the loop l2. At the junction of the tongues with the loop proper there are cutout portions 39 from which the tapering ends 40 of the loop parts 36 and 31 extend to the edges of loop, the cutout portions and the tapering edges providing for the desired degree of movement of the link parts relative to each other. The loop I2 is resilient and in the unassembled condition it is sprung outwardly as shown by the dotted outline of Fig. 4.

The cartridge-receiving members I! and I2 are separately formed from flat metal stock by stamping a blank having the desired outline, bending or otherwise forming the blank into the desired shape followed by heat treating and finishing operations. The member 52 is assembled to the member I I by compressing the loop I2 from the dotted position shown in Fig. 4, thereby pressing the tongues 34 and lugs 35 together and inserting the lugs and tongues through the aperture 23. Thereafter the loop is released and through its resilience it expands to the position shown in Fig. 6 and by the solid outlines of Fig. 4, in which position the tongues 34 at their junction with the loop l2 bear against the curved edges 24 and 25 and the lugs 35 are spaced upwardly from the base 16 of the bridging member. In the event that force is exerted tending to pull the members I I and I2 apart, the tongues 34 are forced to move toward each other by virtue of their angular direction and the lugs come into contact with the base of the bridging member and effectively prevent the links from coming apart. An assembled ammunition belt consists of a number of links with their loops l2 placed between the elements 13 and I4 of adjacent links and cartridges inserted into the three loops in a row.

During use, the ammunition belts make numerous twists and turns thereby placing stresses in the links and causing the various parts of the link to move relative to each other. It is highly desirable that there be as little resistance as possible to the movement of the link parts relative to each other during the twists and turns of the belt while it is being used, so that there will be no more than the minimum load placed on the feed mechanism arising out of the necessity of deforming the links to obtain the twists and turns of the belt. It is equally desirable that there be some resistance *to the movement of the link parts relative to each other to prevent the cartridges from indiscriminately flopping from one position to another due to random causes and that there be some means :to bring the cartridges back into a straight line after displacement therefrom.

' Referring to Fig. 5, the bridging member 15 'of the member II and the lugs 35 of the loop member l2 are shown in two relative positions, the normal position being shown by the solid outline of the lugs and the dotted outline of the lugs '35 indicating the position of the parts when the members H and [2 are turned relative to each Lother so that the axes of the two members are turned in planes which are perpendicular to the plane containing the axes of the two members before turning. Since the edges 24 and 25 are curved and the tongues 34 are fiat, in the normal position of the link members one of the tongues contacts the curved edge or guide 24 at two points M and 42, and the other of the tongues contacts the curved edge 25 at two points 43 and 44, the tongues being biased into the two-point contact by the spring action or resiliency of the loop I2. When the two members of the link are turned to the position indicated by dotted lines, it is seen that each of the tongues has moved to a position where one tongue contacts the edge 24 at only one point 42a and the other tongue contacts the edge 25 at only one point 4311, the points 42 and '43 having moved along the curved edges to the points 4211 and 43a, with the result that the tongues have moved closer to each other, as shown, and thereby have increased the spring force exerted by the loop l2 tending to return :the tongues to the normal position.

The movement of the tongues toward each other is made up of two components. The first of these arises out of the fact that the radius from the center of the aperture 23 to the point 42 or 43 is less than the radius of the curved edges 24 and 25 as previously pointed out. Therefore the curved edges 24 and 25 lie inside of a circle, indicated by the arcs 45, having the center of the aperture as a center and the distance to the point 42 or 43 as a radius. Consequently, when the tongues are rotated the edges of the tongues following the curved edges 24 and 25 are forced inwardly. After the edges of the tongues have moved to the points 42a and 43a, the friction of the tongue edges against the curved edges causes the tongues to become relatively stationary and the tongues pivot about the points 420, and 43a as centers, thereby also causing the tongues to move closer together and giving the second component of movement. The amount of movement of the tongues is limited 'by the fact that one edge of each tongue comes into contact with the bosses or projections 25.

Since the tongues are resiliently biased in the outward direction by the spring action of the loop l2 and the tongues bear against the curved edges or guides at only one point When in the rotated position, it is evident that there is a component of force creating a torque which tends 'to rotate thetongues and return them to the-normal position, :and if the force resisting the return is .not-toogreat, the tongues will com- :pletely return to the 'normal position. Further- :more, the :edges '24 and 25 being curved, the re- :siliencyzof theloop [-2 causes the tongues to seek their .outermost position which occurs when the tongues: are symmetrically arranged in the aperture 2-3 between the ends of the aperture with eachtongue having a two-point contact With lthecorrespondingcurved edge, and thus the member 42 is also restrained from movement in directions along its axes.

Referring :to Figs. 6, '7 and 8 illustrating the relationship of-the elements of the link when the two cartridge-receiving members are turned relative :to each-other so that the axes of the :two members are turned in a plane containingrboth of the axes, Fig. 6 shows the mem- .bers inrthe :normal :position and Figs. 7 and 8 .-show the members in the turned position. In this type :of .turning, if .a series of cartridges .and the assembled links were lying on a flat surface, the :baseswof the cartridges or the noses thereof would .be-pointing toward the center of .acircle.

- Referring.:-first to Fig. 6, it is seen that in the :normal position 50f the members the base It of the bridging member 15 is in contact with the .-lo.op-l 2 substantially-at the junction of the tongues 134 and the loop [2, zthe lugs 35 being spaced upwardl-yirom :thebase 1-6. Referring to Fig. 8 (the turned :position), it is seen that the point of intersection of :one of the tapered ends 46 with the corresponding cutout portion 39 bears 'against the bottom surface of the base 16 at .point 46, and-the opposite edges of the lugs \3-5 bear against .the .top surface of the base l6. In this position the turning movement is com- ;plete and further turning is impossible. During this turning movement the member l2 pivots or iulcrums about points A?! which are the points where the outside surfaces of the tongues 34 .contact the lower (edge of the curved edges or guides .24 and 25. 'Fig. 7 is an end view of the structure shown in Fig. 8, showing the turning movement complete with the lower surface of the lugs 35 .in contact with the upper surface ofzthe bridge 16.

.-It will be apparent that "when the member I2 ;is-,pivotedor turned about the pivot points 41, thehfront edge of the tongues remain in contact with-thecurved edges or guides 24 and 25, and hence by virtue of the fact that the tongues extend :upwardly and outwardly at an angle, the tongueswill be forced inwardly by an amount depending on the angle at which the tongues zextend from the loop 12. This, as well as the amount of the movement, is seen from comparing Figs. 6 and 7. Since the tongues are ressilientlylbiased outwardly, they tend to resist in-' .ward movement and because of such inward \movement there is a greater force tending to lmove the tongues outward, the outward force ha-ving a component along the angular tongues which .creates a torque urging the tongues into the -normal;position. That is, rotating the member J2 lcauses the base It to climb upon the angular edges :of :the tongues to a position of in- .stability, and :unless some force is exerted to :cause it to remain there, it will return to the Flowermost or stable position.

Closely allied with the turning movement describedin connection with Figs. 6, 7 and 8 is a mevement-ofsthe members of the link which may be termed 1stretchin g,=.-inthat the members H and I2 moveapart'with their axes in the same plane. Considering Figs. 6 and .7, and :assuming that there .is no: turning cor twisting but that a downward force :is exerted on .the loop I12 while the bridging member-d5 -iswstationary, the downward forcewill cause-the :loop 42, and consequently the tongues 34, to move downwardly to a position corresponding to the front edge view .of the tongues in Big. v'7, and consequently the tongues are-moved inwardly toward each other.

By virtue :of the angularly extending tongues, the force tending to move .the-tonguesoutwardly has a component alon -the tongues tending to return them .to :theuppermost position shown in Fig. 6 where thflflOWGP-SllfffiCB of .the bridging member touches the loop A2. The movement-of the tongues relative to the bridgingmember I5 is thus resiliently .resisted' and permits th ammunition belt .to elongate resiliently under the jerks of the :gun feedin -:mechanism, etc., thereby preventingshocks to thegun and other equipment. -In anwactual-operation, of course, there will be complex movements, but the total movements ofthe llinktmembers may be resolved into components which are thesimple ones described and the :foregoing-explanations will apply.

While a particular embodiment has been shown, it will be understood, of course, that the invention .:is not limited .thereto since many modifications may b made, andaritis, therefore, 0011'- templated by the appended claims"tocover any such modifications ascome within the true spirit andscope of :the invention.

Having thus' describedithe invention, what is claimed and ldesired ito zbe secured by Letters .Patent is:

1. A cartrige'belt link comprising ;a first cartridge-receiving--member {and a second cartridgereceiving member having. .a normal position relative thereto and havinga limited-degree of move-- ment relative thereto, said first cartridge-receiving member comprising apair-of axially spaced cartridge-receiving elements, :a bridge member connecting said axially :spaced cartridge-receiving elements havin an aperture disposed-between said elements, theredges biz-said aperture defining spaced curved guides, saidsecondmember comprising aresilient single cartridge-receiving ele- .ment and :a "pair of tongues extending vangularly .from said single element through said {aperture :and having a pair 'of'lugs extending laterally from said tongues -for engaging said bridge toconnect said first and second members, said tongues being biased into contact with said-guides by said single resilient element and having substantially flat surfaces contactingzsaid curved guides with a two-point contact, .theradiusof curvature of said guides beingigrealter than :the :-radius extending from thecenter of saidapert-ure torsaid contact points, wherebyssaid movement efiects morement of said tongues :into a single-point contact with said guides rand-thereby creates .a component of force tending :toreturn said tongues :to said position of two-point contact.

2. A cartridge-belt link :compris'ing afirstcar- 'tridge-receiving ;member "and a second cartridgereceiving member having in. normal position relative thereto and having :a "limiteddegree of movement relative to said normal :position, .said :moveme C prisingrotation offthe axesof said members in planes perpendiculantothe planenorma'lly containing the .axes zof said :members, said first cartridge-receivingsmemberzcomprising .a pair. of axially spaced cartridge-ereceiving:.1elements, .ra

bridge member connecting said elements having an aperture disposed between said elements'and curved spaced guides defining the edges of said aperture, said curved guides bein concave, toward each other, said second cartridge-receiving element comprising a resilient single cartridgereceiving element and a pair of tongues extending from said single element through said aperture and terminating in a pair of lugs extending laterally from said tongues for engaging said bridging member to connect said first and second members, said tongues having substantially flat surfaces and bein biased into two-point contact with said curved guides b said resilient single element, said guides having a radius of curvature greater than the radius extending from the center of the aperture to the contact points of the tongues with the guides and having an arcuate extent greater than the width of said tongues, whereby said rotation effects movement of said tongues into a single-point contact with said guides and thereby creates a component of force to return said tongues to said position of two-point contact.

3. A cartridge belt link comprising a first cartridge-receiving part, and a second cartridgereceiving part, one of said parts including aperture means having opposed outer curved edges and the other of said parts including a pair of flat longitudinally disposed tongues extending therefrom at least one of which is resiliently formed, each of said pair of tongues terminating in an outwardly projecting lug, said tongue extending through said aperture means whereby said lugs engage said one part adjacent said curved edges for holding said parts together and the edges of said flat tongues engage said curved ed es for resiliently restraining relative twisting movement of said parts.

JOHN J. MURPHY.

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

UNITED STATES PATENTS Number Name Date 2,302,595 Berry Nov. 17, 1942 2,390,331 Sanford Dec. 4, 1945 FOREIGN PATENTS Number Country Date 355,767 Great Britain 1931

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