US2452076A - Gun mount - Google Patents

Description

Oct. 26, 1948. SPENCER 2,452,076

GUN MOUNT Filed Feb. 7, 1944 3 Sheets-Sheet 1 CAM mrAJiJM 4 Oct. 26, 1948. M. c. SPENCER GUN MOUNT 3 Sheets-Sheet 2 Filed Feb. 7, 1944 gwuc/wtoo Myrmn Cfipencnar Oct. 26, 1948.

M. C. SP ENCER GUN MOUNT 3 Sheets-Sheet 5 Filed Feb. 7, 1944 Myr on Patented Oct. 26, 1948 GUN MOUNT: Myron'C-i Spencer, Ocean Grove,-'N; J; Application February 7, 1944, Seriat No.l521,-3.76

2 Claims. (01? 89"37 (Granted"under' the act of: Marclu 1883; as s amendedApril-30, 1928; 370 0. G. 757) The invention described herein-may be man'- ufactured and used by or for the Government for governmental "purposes i without the. payment to me of any royalty 'thereon'.

This invention relates .:to rquick-action traverse andelevation' changing -gun mounts and: mountsv of similar action for other purposes.

The 'invention has for an'aobject'sto present a construction in whicha single gunner may operate the gun quickly bOUhJIOFZtIaVEISGaIId elevation andl'at the same time'fire the gun when of'an automatic loading type;withiazhighvv degree of accuracy, as comparedtosconventional' mounts.

It'is an'important object to relieve the gunner from the expenditure-of much. effort -'and energy now involvediby the conventionalnmount for a hand-pointed gun, wherein the gunner walks around-the gun as it'isswunggin-traverse'and at the same time it issought to giveithe. gunner a more steady orientation .in .relationrto the 2 gun without theeneed for shoulder rests, stockspand the like.

A' further pur.pose-is:to enable .the gunner "to more tefi'ectively concentrate: mentally/on the movement of theatarget' and the factors entering into the aimingi. of the "piece; notwithstanding that quicker movements of: thesgun': inf-traverse andelevation are possible; which are furtherobjects .of the invention.

Another object 'is'torpresent amount in which some 1 basic desirable features of" conventional mounts maybe embodied: yet:eliminating the nieedz for: many others; so that ithe .tmount may be simple to produce, at the same timethat'improvements: herein". enumerated: are attained.

Thus .it is: sought toLeIiminateL-the need for .the heavy 3-position trigger; frame .mechanism': and grip. structure andsenable izthleeuse of a simple pistol griprandtrigger. immediately at the gun; Also the sight may be greatly: lightened :and r10- catediclose to the axis of'the gun; reducing errors in: calculating or estimatingzpara'llax-angles, which is specially. important in'close range-'anti-air :craft fire;

It is: an important aimito attain .the rlast'named improvement without requiring: excessive height in themountp.

A furtherximportant aim of? the invention" is toxenable uthe "gunner :to sight the 'weapon :without; stooping,i.duckingi or cooking his. head :at any awhwardzangles:

A=stil-l further-attainment. inTVieWT is "to. enable greater 1useofspace .near. the .gunnfo'r otherpurposes ;-such:as. accommodation: of CIIlBl'ITOIT material in:trucks:onrconfinechisituations;: andi-on: ship;

board to'enable the placing of a gun near storeson gear: when not 'heretofore'possible. One important use which it is sought to attain is :the possibility of mountinga machine gun. so

1 that it"maybe=moved-:with its mount instantly from an out-of the-waysituation toan' attack or .firing position; as; for instance on a. swinging.

bracket, which in fighting position may extend laterally from a: truck 'body; or the side of avessel.

or barge,

In the attainment ofthese and 'other. "objects and ."advantages, as apart :of the embodiment :of the invention, I have utilized" agear drive. for traverse-1operatedfby pedal cranks in this ine stance, audit is a very important object of the invention to enable:an independent free manual. swingingtof :thegunzfor traverse, and .so 'make the pointingof the gun independent Iof-the gear connections within proper limits yetretaining the advantage and benefit of the-quick rotation of the gun assembly and gunner on'the'mount by pedal action: In this way uncertainty of azimuth adjustment due to lost motion or back lash in gears is obviated.

Additional objects, advantages-and features of invention' reside in'the construction, arrangement and combinationof parts involved in the-embodiment of 'theinvention as will appear from'the followingdescription and accompanying drawings, wherein:

Fig; 1 is aside elevationof a mount, the pedestal shown partly'in section; constructed in accordance with my invention; a;gun and sight being fo'rmallyshown, though" not incomplete detail or proportions andparticularly. as to the gun, since gun. forms adaptedoriadaptable .to .use on my mount are known, and the gun comprises no novel part of 'myfl-invention.

Fig. 2.;isa rearelevation of Fig..- llwithhupper. portion of the extensible sleeve shown partly, in section.

Fig.3 isa cross sectionon the linel33 of Fig. 1.

' Fig.4 is acrosssection-on. the line-4--4 of Fig.1.

Fig; 5 is across sectionontheline 5,5 of-Figrl;

Fig- Sis across section taken generally;on the line-.i-5 of Fig. 1, the. pedal being-shown in its: lowermost position,

Fig." 7 is an enlarged-side elevation partly insection.--

Figx8 is a similar View of I a modification.

Fig. 9' is a schematic ---detailv of-;a-valve -for 'the modification, in raisingposition.

Fig. 10 is a schematicdetail of a valvefor the modification, in lower-ingjpositiom Fig. 11 is a schematic detail of a valve for the modification, in stopping position.

Fig. 12 is a detail elevation of the crane arm mounting.

Fig. 13 is a fragmentary top view of the last' named, illustrating the operation of the locking flange, I

Fig. 14 is a rear elevation of a truck on which my invention is incorporated.

Fig. 15 is a side elevation of a cradle mount element, the base of the mount omitted. The seat, not shown, would be attached to the left hand side of the standard I F32 as shown in this view.

Fig. 16 is a rear elevation of Fig. 15.

Fig. 1'7 is a section on the line l'l-l'l of Fig. 15.

Fig. 18 is a detail of a modification of the pedal drive.

Fig. 19 is an enlarged section of the base of the hydraulic mount.

Referring to the drawings by characters of reference, there is illustrateda mount comprising a pedestal or foot mounting 15, consisting of a base plate M which may be the same size as that of a well known prior pedestal mount, fixed or integrally formed on which there is an upstanding body l6 horizontally flanged at its upper part to permit attachment thereto of a bevelled ring gear IT. A simple step bearing recess is formed in this body, concentric with the gear, and stepped therein is a vertical shaft 58 of substantial dimensions for the uses contemplated.

Base traoerse.Diametrically arranged radial stud shafts or pins H] are fixed at opposite sides of the shaft M3, on which there are revoluble respective small bevel gears 2!) meshed with the gear I1, and keyed to which are pedal crank arms 2|, having conventional pedals 22 similar to those used on bicycles. Conventional crank construction such as used in bicycles with gear drive may be substituted if desired. The gears are so meshed with the ring gear as to position the cranks on opposite radii of the aXis of the small gears, and the cranks will be so maintained thereafter throughout the operation of the device.

Seat-At a suitable distance above the gears w a seat bracket arm 23 is mounted on the shaft I8, consisting of fiat, steel piece longitudinally slotted at its base and held to the shaft adjustably as to height by means of thumb screws 24 or other fastening. The arm extends diagonally upward and outward from the shaft and carries at its upper end a conventional form of seat 25 suitable for the uses indicated.

Accommodation of line of sight and eye 'level'.-

Slidable on the shaft, there is an extensible sleeve '26, and mounted thereon is an elevator pinion 21 meshed with a rack 28, formed on the shaft la in line with the seat bracket, the pinion being operated by a hand wheel 29 and crank handle 30, by which the sleeve may be raised and lowered on the shaft i8.

Free pointing action.Means are provided on the upper end of the sleeve 26 for mounting a gun, where there is swivelled a pivot yoke 31, having upstanding parallel ears 32' between which there is fitted a rocker head 32, supported by an elevating pivot pin 33 engaged through the ears and head 32. The rocker head is connected by a neck or radial extension 34 to the frame 35, cradle, or other part of the gun or parts to be assembled therewith. The swivel 3'! includes an upper head part 36 of the same external diameter as the sleeve 26, and is relieved at its lower part so as to form a shoulder 31 which in this instance rests directly on the upper end of the sleeve 2-6 to revolubly support the swivel, the relieved part of the swivel may be termed a stem 38 which fits snugly and revolubly in the sleeve, extending downwardly in the sleeve a substantial distance to maintain a stable axial relation to the sleeve and shaft. At an intermediate part of the stem 38 a flat bottomed circumferential groove 39 is formedon the stem 38, and engaged through the wall of the sleeve there is a retainer screw 40 or more, projecting into the groove so as to hold the shank revolubly in the sleeve.

At the upper end of the sleeve a broad shallow slot M is formed, open on the end of the sleeve and on the swivel yoke 31 2. lug 4 2 is formed as a continuation of the peripheral material of the head 36 extending below the shoulder 31. The lug is narrow enough to permit its movement from side to side in the slot under corresponding rotary movements of the yoke 3! on the axis of the tube, and thereby such rotation is limited by'engagement of the lug against either side of the slot. This will correspondingly limit traverse of the gun when the shaft I8 is stationary. The shaft [8 ,maybe retained in its bearing in the foot piece l5 by any suitable means, a C-spring 43 being shown in the present instance, contracted into a groove 44 formed on the outer periphery of the shaft at a level with the under side of the ring gear, the spring being of such transverse measurement as to engage under and be held against upward movement by the gear. The inner bearing surface of the foot piece is relieved or rabbeted at its upper part to accommodate the C-spring. The relative movement of the swivel on the sleeve 26 may be from fifteen tothirty degrees or more and if desired a yielding means may be incorporated to yieldingly oppose movementof the lug 42 when nearing either end of the slot 4!.

' Foundation support.1n one use of the inven tion as a gun mount or searchlight control, the base plate I4 is mounted on the outer end of a crane arm 45, which may have a plate 46 of a size the same as the plate l4, to whichthe latter is bolted or clamped, clamping devices being now in use suitable for such purpose in gun mounts. The arm is formed with horizontal upper and lower ears 41 and 48 held by a king pin 49 which is revoluble in a knuckle 50, formed on a substantial bracket plate 5| adapted to be bolted to side plates or frame of a truck 45, tank or other structure. The knuckle is formed with a semicircular bearing flange 52 based on the plate 5|, and having peripheral notches 53 therein a each side near the plate, and a central notch 54 on' a radius normal to the plane of the plate. On the inner and under side of the ear 4'! there is pivoted an L-shaped dog or latch lever 55 having a short latch arm 56 adapted to enter any one of the notches 53-54 when alined therewith and a normally pendent long operating arm 51 the extremity of which lies near but stops short of the lower ear 48 of the crane. The lever 55 is thus operable to hold the crane extended when the lever engages the central notch 54 or hold it retracted close beside a supporting structure to which the bracket 5! may be attached.

Any usual expedients used in prior mounts and applicable here may be added as discretiondictates. Due to the fact that many such are known in readily applicable form, I have not disclosed clamps for limiting traverse, vibration and recoil cushioning means in the mount, ball bearings and other anti friction bearings applicable in the step .where.

hearing, .the swivel and otherwise mounting of ammunition case on the gun, toe clips 'on'the pedals, andmeans'to limit depression of the :gun too far when among ownrtroops or to limit traverse where necessary. The formal representation of a gun 60 which is made in the drawings is not intended to represent any perfected gun knowrrbut includes a schematic'indication'of an air cooled barrel 58, a framing structure 35 and pistol grip and trigger at 6 I In the use of the mount as describedyit may have the foot plate l4 bolted toa deck, or toxan adapter plate of greater radius to afford a stable :base to be bolted to a wood deck or for other rea- 'sons,.such added base elements being well known. Also a-well known form of tripod leg assembly may be provided on the foot piece I5, these being well known and therefore not illustrated.

Operation.In operation, assuming the mount built substantially in the 'specific'form illustrated in Figs. 1 to 9, the gun mounted on the swinging crane arm 45 is positioned close beside the body of the truck 55', and the gunner may be either in the seat 25, or in the body of the truck, or else- In case the truck is one with bows on which a covering material is disposed, the gun and mount are preferably positioned with the muzzle of the gun and the seat in a Vertical plane parallel to the side of the body, the gun having its .muzzle either forwardly or rearwardly with respect to the truck. It will be so held by engagement of the latch 55 in the respectivenotoh- 53. For action, the latch 55 is disengaged .by swinging the arm 51 outwardto clear the arm-56 from the notch and the crane arm swung outward to position at right angles to the side of the-.truck,-the latch 55 then engaging in the notch 54 either by action of gravity on the long arm 51 or by manual or spring pressure on the latter. When the arm is swung outward and latched in place, the gunner may now take position in'the seat 25, with his feet on respective pedals, grasping the grip iii inone hand and the elevator wheelor crank 2930. The target being in view or otherwise located, the

gunneroperates thepedals to drive the planetary gears 20 on the large-gear-l'l until the shaft i8 is turned so as to present the gun'in an azimuth plane approximating the position ofthe target, and by the grip 6! gives the gun an elevation approximating that which will produce 1a trajectory of proper range. 'Should the line of sight be higher than a convenient level of the gunners eye, the-wheel'29 is operatedtolo-werthesleeve until a sight may be efiectivelyand conveniently Should the-lineof sight be such-as to taken. require the gunner to hump his back and duck his head, or either, the wheel -29 is operated to elevate the sleeve toaccommodate the line ofsight to his eye while he-assumes a normal posture.

The target being in sight, more definite azimuth 1 and elevational aim is efiected by moving the-gun on the pin '3'3-as a pivot touattain properelevation and by'rotatingthe gunxby. hand on the vertical axis of the swivel 3 l and including the swivel head, independently ofthe pedal drive.

In case the target is a moving one at a considerable distance the gunner makes no-eifortto'obtain a fine azimuth sight'by-the use of the pedals, but

only initially obtains a meanor near position of the gun in this respect, thereafter pointingthe weapon by theindependent movement which is not aifected by pedal'operation. As thetarget moves one way or another beyond an angle of five or ten degrees or some practical maximum, the

pedals maybe operated to: move thegunnerzzand "6 shaft i8to or toward "the proper azimuth plane. This movement may be efi'ected during firing while the gun is independently held on the target by-the grip 6| or other traverse means,'or the pedals maybe operated during intermission of firing.

In the case of a'rapidly moving target, especially one moving on a'tangent of a short radius from the gunner, the coordinated use of the pedal and hand traverse become specially important and valuable. Also the'rapid change of elevationof the gun under such circumstances will make the useof the sight level accommodation means a most valuable adjunct since it avoids disturbance of the physical balance of the gunner, enables him to use his eye with atnormal posture of the body and head,.and obviates the distraction involved in stopping around over obstructions or groundinequalities and disturbances of balance such 1 as may occur for instance when a tripodleg compels taking a posture Without the'gunners feetbeing symmetrically adjusted to the center of gravity of his body.

Various servo motor devices or power'means may be applied to the movementsof the-gun in elevation and traverse where practicable, and also to the raising and lowering of thegun translatively'in placeiof the wheel 29 and .rack 2'8. Thus in Figures 8 to 11 inclusive, I have shown a construction wherein the raising and lowering'are' accomplished hydraulically, so that a fluid supply under pressure may be maintained'by well'known means and the-mount constructed as a hydraulic jack for raising and lowering the gun translatively.

Hydraulic lift-Here the hydraulic foot piece .65, Fig. '19, corresponding to the one !5 and similar in form, has a pressure oil conduit fitting 66 connected by flexible or other conduit 67 to anoil pump not shown. From the fitting '66, an inlet port or duct 68 opens into the central bore 690i the foot piece, while a short distance thereabove an outlet port or duct :lfi'opens'radially from the bore to 'a'return or vent conduit H which may be connected to the intake of the oil pump or a reservoir. A ball bearing 12 supports in the bore a revoluble steel shaft or standard 73 circularin cross section from the bottom of which two rectilinear bores 14 and 15, parallel to the axis of the standard, extend to a level some distance above the throw of the pedals'22 of this machine. A ring gear l1, planetary gears 25, crank 2| and pedal 22 assembly are included, similar to that first described, the standard being retained a ainst upward movement bya .C-spring -15 engaged in a .groove-in-the standard and confined by the ring gear as before. The bores both'open laterally through the -face of the standard and .are counterbored and threaded to receive flexible conduit connection nipples Tl and 78 for purposes .to be described.

The bore 75 is plugged at the lower end of the standard and a lateral vent port 79 formed therefrom through the side of the standard at the same :level-as the ventduct N3 of the foot piece. A hori- The standard is also bored from the top downward to provide a single large combined inlet and outlet bore or duct 83, stopping short of the upper terminations of the bores M and I5. A radial bore 84 is extended through the side of the standard from bore 83, forming a combined cylinder inlet and cylinder outlet 84 and including a nipple 85 for connecting flexible conduit thereto.

On the standard there is slidably fitted a cylinder 86 corresponding to the sleeve 26, but, contrary to the first described fOIm no rack and pinion are incorporated, and no swivel piece is mounted for relative rotation on the cylinder. Instead, ears 9'! corresponding to those 32' first described are fixedly provided on the upper end or head of the cylinder, and between these ears the rocker head or knob 32 may be pivoted as first described, or other mounting of the gun for elevational movements provided. The gun will still be swivelled for free movement, since the cylinder is rotatable freely around the standard. This free rotation may be unlimited or not, in this device, as discretion may dictate.

On the standard near its upper end a series of packing rings 88 are fitted in corresponding grooves 89 in the periphery of the standard, and slidable in the cylinder.

To effect raising of the gun translatively, or to lower it, or to hold it at various positions, in this translative movement on the mount, I have provided a conventional three way valve 99 mounted on the outside of the cylinder 86 above the inlet 84 in any convenient manner as shown in Figure 8, although various forms of valves suited to' the functions required are available. In this instance the valve is shown as a simple plug type valve,

includinga case 9! of circular form having a conical seat 92 through which open radially a pressure inlet port 93, a larger vent or return port 95, and a combined inlet and outlet port 95. A plug valve 96 is fitted to the seat having a segmental closure part 91' of sufllcient extent circumferentially to close only one of the ports at a time, and having means .to stop its movement toward the pressure inlet port, so that the latter is never closed. The latter in this instance is illustrated at the upper side of the case in Figs. 8 to 10 and the other two ports diametrically opposite each other on a diameter normal to the radius of the port 93.

With the segmental part 91 at the position shown in Fig. 10 all three ports are open and oil or other liquid from port 93, as well as from liquid port 95 is free to the vent 01 return port 94.

The valve is suitably fixed on the outside of the cylinder 86 conveniently for operation by the gunner in the seat 25, and from the nipple 85 a fiexible conduit 98 with a suitable slack loop is extended .to and connected to the valve in communication with the port 95. From the nipples TI and 18 similar connections 99 and I99 are made with the ports 93 and 94 of the valve.

Operation The last described form of the invention may be mounted on a swinging crane or deck the same as first described and in the case of the crane adequate provision of slack in the leads (not shown) to conduits 61 and H should be made and conventional precaution against fouling may be included. Assuming that the gun is positioned and ready for operation with the gunner seated at the gun, the approximation of azimuth position is effected by the pedal operation as before, and the exact azimuth pointing accomplished independently by pivotal movement of the gun and cylinder 86 by hand. No means is indicated to limit the relative rotating movement of the cylinder and standard, since this will be automatically limited by the position of the gunner on the seat '25. Elevation of the gun for range is effected conventionally. Translational raising and lowering of the gun and cylinder are controlled during firing or intermission of firing and during change of elevation and azimuth pointing if necessary, by operating the handle IOI of the valve to the desired position. With the valve in the position shown in Fig. 9 the outlet port 94 is closed and the pressure liquid is admitted from the conduit 61 through the space under the lower end of the standard, small bore I4, nipple 'I'I, flexible conduit 99 and port 93 to the valve case, from whence it passes outward through the two way port 95 and flexible conduit 98 to the bore 83, thus exerting its hydrostatic pressure in raising the piece, when the gun has reached a proper level, it may be held at a fixed elevation by turning the valve to the position shown in Fig. 10 the port 95 is closed, thus sealing in the cylinder whatever liquid may have gained access to the cylinder. For lowering the gun translatively the valve is returned to the position of Fig. 1 with the resultingventing of the liquid both from the cylinder and the pressure port, to the large outlet port 94', flexible conduit I09 and bore I5, groove 80, duct I9 and conduit II, to the reservoir and/or pump not shown.

CTadZe.In Figs. 15 and 16 I have shown a cradle support for the gun at the top of the rotating base pivot head on the upper telescoping member or sleeve, and also a construction by which an extreme elevation may be given the muzzle of the gun without causing interference between the head of the gunner and mount, when the breech of the gun is close to the pivot on which the elevational movement occurs and to the vertical axis of rotation of the gun. In this instance, the construction of the gun may conform to the embodiment first described except that the uppermost member I02 of the mount rotatable on a vertical axis is formed with a horizontal offset or crank arm I03, the outer end of which is turned upwardly, and has the swivel 3 I mounted thereon as in the case of the swivel 3| before described, in place of the ears 32' however, a sector plate I04, in the form of a narrow segment of a hollow cylinder with horizontal axis is fixed on the extremity of the ofiset with its ends directed upwardly but subtending less than degrees, the chord disposed at an angle of 45 degreesor less to the horizontal and the lower part of the segment being toward the position of the gunner. This sector plate has parallel lateral edges and the abutting edge portions project at each side so as to afiord continuous edge portions I05 engaged between upper and lower guide flanges I05 carried by side frame and guide plates I98, one at least being separable for ready removal of the gun. The plates are fixed on the framing or other suitable parts of the gun or breech mechanism. On one of these a grip and trigger I99 is mounted on a tongue III] of suitable material extended diagonally and divergently from the axis of the gun, so that the hand of the gunner and the grip will not interfere with the head of the gunner in sighting the piece, as may be appreciated from the views in the drawings.

Operation (Figs. 15 and 16) In the use of the last described form of the invention, with the side plates I08, the pedal devices are employed as before, and independent pivotal movement of the gun and elevational pointing are effected as before described, as well as translational raising and lowering of the gun. Due to the use of the sector and guide frame the axis of pivotal movement of the gun is located nearer the gun axis and also the breech end of the gun is brought forward near the axes of pointing movement. This lessens the extent of translative vertical movement of the gun required to accommodate the position of the gunner to the line of sight, as may be understood from the illustrations of this form of the invention. In this construction the forward end of the sector plate may serve as a stop for movement of the gun muzzle downward.

It should be noted that while the gun is ofiset laterally from the vertical axis of the main stand ard portion of the mount laterally with respect to the direction in which the gunner normally faces, it is not necessary to similarly ofiset the gunners seat or the pedal drive assembly, as the offset is so slight that the gunner can easily sight the gun without a strained position, and effect the operation of th gun and raising and lowering devices.

It will be understood that the ofiset I03 may be omitted and the sector plate I04 mounted on a simple end of the cylinder or the swivel of the first described construction.

It is thought unnecessary to illustrate the substitution of a binocular in place of the gun for Searchlight control, or the mounting of listening devices in place of the gun, since the operation of the mechanical essentials of the invention will be much the same. In the case of a listening device using electronic relays, it is not always necessary to aline the eye or ear of the operator with incident sound waves, but the mechanism described will enable rapid and accurate direction of the sound receivers, and a fin following of the course of a moving sound source, and the translational raising and lowering device may be disregarded to a large extent. However, where a number of planes are within sight or may be seen by optical instruments, it may be of advantage to use a binocular on the mount associated with a sound locator by Selsyn control and drive so that particular planes may be selected to determine identity or range where possible by distinctive sounds. These adaptations will be readily understood and the operative means for the controls being already available and in use are not illustrated herein.

In other instances a searchlight or sound Number cator may be mounted directly on the mount in place of the gun, for direction at or toward targets or other objects.

In place of the swinging crane any other form of extensible support may be employed, slidable or otherwise.

While illustrated as being in two halves bolted together at a diametrical joint, the foot pieces 15 and 55 are each preferably formed in one piece if cast, and then suitably bored to afford the necessary bearings, this being a matter of dis cretion and not illustrated.

I claim:

1. In a mount of the character described, a base, a primary person carrying mount element mounted for rotation on a vertical axis, and a final mount portion consisting of a cylindrical upwardly presented open end member rotatable with the primary mount element, and a head part rested on said end and having a shank portion set revolubly in said end, a recess being formed in said end extending over a part of its circumference, a lug on the head movable in said recess to limit relative rotation of said head on the mount, and a rocking support for an instrument on the head.

2. The structure of claim 1 including resilient yielding motion limiting means between the lug and the ends of the recess in respective directions of relative movement of the lug.

MYRON C. SPENCER.

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

UNITED STATES PATENTS Name Date Rolle Dec. 3, 1901 North May 27, 1919 Giangiopo Sept. 28, 1920 Baker Apr. 14, 1931 Larsson et al Feb. 20, 1934 Trimbach Nov. 3, 1936 Rarey Jan. 17, 1939 Poysa May 12, 1942 Fogle Apr. 4, 1944 Veit June 27, 1944 Scott-Paine Sept. 12, 1944 FOREIGN PATENTS Country Date Great Britain 1915 France Dec. 18, 1928 Italy Jan. 22, 1936 Number

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