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Publication numberUS2403170 A
Publication typeGrant
Publication date2 Jul 1946
Filing date29 Nov 1941
Priority date29 Nov 1941
Publication numberUS 2403170 A, US 2403170A, US-A-2403170, US2403170 A, US2403170A
InventorsBussiere George A, Chapman James E
Original AssigneeNorth American Aviation Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Ammunition feed booster
US 2403170 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

i n mmm N m m MW v 0U A 7 EA 6 0 2 4 mr 3 4 a n .v w w lnlu 9A, F 6% m m y 1945- J. E. CHAPMAN ETAL AMMUNITION FEED BOOSTER Filed Nov. 29, 1941 Patented July 2, 1946 UNITED STATES PATENT osrlct:

James E. Chapman, Los Angeles, and George A. Busslere, Inglewood, GaliL. asslgnors to North American Aviation, Inc., Inglewood, CallL, acorporatlon of Delaware Application November 29,1941, Serial No. 30,958

'lClaims. I

The present invention relates generally to means or mechanism for boosting the feed of ammunition belts to machine guns, especiallythose guns for which it is highly desirable to store large quantities of ammunition at a point substantially remote from the guns, and has for its primary object the provision of a mechanism which may be readily regulated and adjusted so as to act solely in conjunction with the conventional ammunition feed ofthe gun in the ammunition feeding operations, to thus avoid all danger of overfeeding, and at the same time permit of manual feed of the ammunition belt at any time this becomes necessary or desirable.

It is well known that in the use of machine guns in airplanes it is desirable, on account of limited space immediately adjacent the gun, to feed thereto ammunition belts from a storage point some distance from the gun. It is also true that modern requirements for shells of increasing calibre have increased the weight of the ammunition belts and the difficulties in properly feeding the same, from a remote point of supply or storage, to the gun. These factors have resulted in over-taxing the conventional ammunition feed of the gun, and it is for this reason a major consideration of the present invention to provide an efficient means of boosting the feed of the ammunition at a point betweenammunition storage and the conventional feeding mechanis'm at the gun, which will efficiently assist the latter in its feeding operations and effectively take care of the greater length of ammunition belts and their greater weight under modern demands.

A further object is the provision of an ammunition feed booster, of an electrically operated character in connection with means eflective to synchronize the boosting impulses thereof with the feeding operations of the conventional ammunition feed at the gun.

A still further object is the provision of a booster unit which will be compact, of small size, and capable of ready use at any one point, or several points, in the line of ammunition feed to the gun.

With the foregoing in mind, the invention will be now described in detail in reference to the accompanying drawing, forming a part of this specification, and in which,

Fig. 1 is a side view, illustrating the practical application of the booster in connection with an ammunition belt.

Fig. 2 is a detail vertical longitudinal section taken substantially centrally through the booster. r

Fig. 3 is a diagram of the motor circuit of the booster controlled by the firing key operation of 5 the gun. I

Referring now-particularly toFlgs. 1 and 2, the invention contemplates theprovision of a booster unit in which a feed sprocket It, for an ammunition belt A, which sprocket maybe sultably mounted in the feed line of the belt between the gun and an ammunition storage station, has imparted. thereto, rotatable step by step. feed movements from a motor II. This motor is shown encased within the sprocket, the latter 16 being hollow for thi purpose, andthe motor being supported at one end in connection with-an end plate l2.

The plate l2 closes one end of the sprocket l0 and may form part of any suitable support maingo taining the unit as a whole in the desired position for use. Plate l2 may also support an adjustabie member at is for adjusting the brushes of the motor Ii to control its power output.

However, thi may be accomplished by control-' ling a rheostat 44 through adjustable member iii, the object of such control being to so regulate the power output of the motor substantially below that required for ammunition feed so. that it will function only in connection with the operation of the conventional ammunition feed of the gun. i

The motor may support rollers M or other anti-friction members therearound for the spacing and rotatable support of the sprocket l0, and

drives the latter through reduction gears l5 at the opposite internally toothed end of the sprocket, and through a magnetically controlled clutch indicated at I6, 0 that when current is cut off from motor, ii, the sprocket is permitted to free wheel and allow manual manipulation or feed of the ammunition for any reason, as for instance failure oi. the gun to fire through a defective shell. 1

The last mentioned end of the sprocket In carries a closed end piece ll which has rotatable bearings l8 in an end frame It. This frame is and the first mentioned end plate i2 may cooperate to support a shield 20 along and spaced from the sprocket ill to hold the ammunition the sprocket, as best' seen in Fig. 1.

The end plate I! may have a socket 2| for reception of a current feed plug for supplying current to the motor,-and the magnetic clutch belt A in properly meshed feeding relation with at 22 and a driving plate 40 connected to be driven by the motor II, as suggested at 4|. The clutch plate l8, which floats between the plates 22 and 40, is mounted on shaft 42 which also carries gear 43 of the reduction gearing ll. A spring 23 tends to move the shaft 42 to the left in Fig. 2, thus tending to disengage the driven plate 16 from the driving plate 40. A magnetic coil 46 is connected in parallel with the motor. When the coil 46 is energized, the magnetic current attracts the driving plate 40, thereby pulling the driven plate It from the brake plate 22 and against the driving plate 40. When the circuit is broken, the magnetic attraction ceases and the spring 23 is permitted to move the clutch plate I6 to a braking position against the brake plate 22. The braking action stops rotation oi the gearing l by stopping rotation of the enmeshing gear 43. The said braking mechanism tends to prevent rotation of the sprocket II) when the motor circuit is broken. A hand piece 24 is provided at the outer end of the shaft 42, to manually shift the clutch plate I6 away from the brake plate 22 so that the sprocket l0 may free wheel.

According to the diagram of Fig. 3, closure of the firing switch 25 in the line 26 from a suitable source 21 of current and the firing solenoid of the gun, feeds current into the line 28 through the motor II to ground, to thus operate the booster motor.

In the motor line 28 of Fig. 3, there is shown a knock-out switch 32, which is normally closed in operation. This switch is shown in Fig. 1 as controlled by an arm 35 normally held, in a position to maintain the switch closed, by its contact with the ammunition belt A. When the end of the ammunition belt passes the switch 32, arm 35 drops and the switch opens to thus prevent further motor actuation of the sprocket. It is contemplated such a switch arrangement may be used at a point in the ammunition feed line, so that when it is opened there will remain only a portion of the ammunition belt that the con- .ventional feed of the gun is well able to take care of without assistance by the booster. This arrangement obviously need not be used except where there is possibility of buckling of the ammunition belt.

The invention as shown and above described supplies a small, compact unit capable of installation in approximately the space normally occupied by the guide sprocket alone, as well as one which may be manufactured as a standard ammunition feed booster for all installations where such a booster may be needed.

While we have illustrated and described what we now regard as the preferred embodiment of our invention, the construction is, of course, subject to modifications without departing from the spirit and scope of our invention. We, therefore, do not wish to restrict ourselves to the particular form of construction illustrated and described, but desire to avail ourselves of all modifications th'at may fall within the scope of the appended claims.

1. An ammunition feed booster for machine I structed and arranged to resist rotation of the sprocket when the circuit is broken.

2. An ammunition feed booster for machine guns including a hollow sprocket, an electric motor within the hollow of the sprocket. gearing operatively connecting the motor with the sprocket. a brake means, a floating clutch plate having braking, neutral and motor-sprocket-connectlng positions, spring means tending to move the clutch plate into engagement with the brake means for its braking position, a magnetic coil disposed when energized to move the clutch plate into its position of operatively connecting the motor with the sprocket against the action of the spring means, and means to move the clutch plate into its neutral position for disconnection from the sprocket and rotation of the sprocket independently thereof.

3. A feed booster unit for ammunition feed belts, including a hollow sprocket, a motor therein, reduction gearing connecting the motor in driving relation with the sprocket, a magnetic clutch between the motor and said gearing for connecting the motor and gearing when said clutch is energized, and an electric circuit including said motor and said magnetic clutch arranged for simultaneous operation thereof.

4. An ammunition feed booster for machine guns including a sprocket and an electric circuit comprising an electric motor and magnetic clutch means, said clutch means being positioned between the motor and the sprocket whereby to actuate the clutch to drive the sprocket when said circuit is energized.

5. An ammunition feed booster for machine guns including a sprocket and an electric circuit comprising an electric motor and magnetic clutch means, said clutchmeans being positioned between the motor and the sprocket whereby to actuate the clutch to drive the sprocket when said circuit is energized, said clutch means including a braking element for stopping rotation of the sprocket upon deenergization of the circuit, and means for manually releasing the braking element so as to permit free rotation of the sprocket while the motor is deenergized.

6. An ammunition feed booster for machine guns, comprising a hollow tubular sprocket, an electric motor within said sprocket and comprising bearings for said sprocket, a motor shaft having a driving clutch plate, reduction driving gearing arranged for driving said sprocket, a rotatable driving shaft for said gearing constructed and arranged for longitudinal displacement and having a driven clutch plate thereon engageable with the driving clutch plate, a fixed brake plate, means biasing said driven plate in engagement with said brake plate, a power circuit including said motor, and means operative when the circuit is energized to displace said driving shaft and driven plate out of engagement with the brake plate and into engagement with the driving plate.

7. In combination, a gun firing means, an ammunition feed booster including a sprocket, and an electric circuit comprising said gun firing means, an electric motor and magnetic clutch means, said clutch means being positioned between the motor and the sprocket, whereby said ammunition feed booster and the firing means are actuated during energization of the circuit.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2453786 *24 Apr 194616 Nov 1948United Shoe Machinery CorpFeed mechanism for rapid-fire guns
US2466975 *6 Aug 194512 Apr 1949Hughes Tool CoSprocket adapter
US2521346 *28 Oct 19445 Sep 1950Bristol Aeroplane Co LtdAmmunition feed mechanism for machine guns
US2541530 *5 Mar 194513 Feb 1951Curtiss Wright CorpAmmunition feed and control system
US2542200 *14 Feb 194720 Feb 1951United Shoe Machinery CorpAmmunition supply system
US2557441 *1 May 194419 Jun 1951Harvey Machine Co IncFeed for guns or the like
US2608598 *22 Jul 195026 Aug 1952Clark Equipment CoMotor-in-wheel drive
US2617330 *10 Mar 194811 Nov 1952Reconstruction Finance CorpAmmunition booster
US2629288 *10 Oct 194724 Feb 1953Hughes Tool CoAntirollback brake for boosters
US2719459 *13 Jun 19494 Oct 1955North American Aviation IncAmmunition booster
US2735811 *13 Dec 194521 Feb 1956 Reactor control
US2757576 *7 Feb 19497 Aug 1956Garrett CorpAmmunition feed booster
US2823588 *6 Apr 195518 Feb 1958Hipsley William BAmmunition booster
US2843021 *1 Dec 195215 Jul 1958Garrett CorpAmmunition booster with torque limiting device
US3164915 *23 Feb 196212 Jan 1965Caterpillar Tractor CoReduction gear type motor grader blade lift mechanism
US4016757 *5 Nov 197512 Apr 1977Remington Arms Company, Inc.Apparatus for testing flexibility of ammunition link belts
US4068557 *14 Oct 197617 Jan 1978Paul Rene MontjallardAutomatic weapons having a cartridge belt feed
U.S. Classification89/33.5, 310/67.00R
International ClassificationF41A9/00, F41A9/51
Cooperative ClassificationF41A9/51
European ClassificationF41A9/51