US3608424A

US3608424A - Feeding mechanism of an automatic cannon for firing caseless ammunition

Info

Publication number: US3608424A
Application number: US864849A
Authority: US
Inventors: Harold H Wiese
Original assignee: US Department of Army
Current assignee: US Department of Army
Priority date: 1969-10-08
Filing date: 1969-10-08
Publication date: 1971-09-28
Anticipated expiration: 1988-09-28
Also published as: CA927162A

Abstract

THE FEEDING MECHANISM OF AN AUTOMATIC CANNON INCLUDES A FOUR-CHAMBER DRUM WHIH IS SELECTIVELY DRIVEN IN OPPOSITE DIRECTIONS BY A REVERSIBLE ELECTRIC MOTOR. A GENEVA MOVEMENT IS OPERATIONALLY DISPOSED BETWEEN THE MOTOR AND DRUM TO PROVIDE INTERMITTENT ROTATION THEREOF FOR SUCCESSIVELY ROTATING EACH OF THE CHAMBERS TO FOUR STATIONS INCLUDING A FIRING STATION, AN EJECTION STATION, AND TWO LOADING STATIONS OPPOSITELY DISPOSED THEREBETWEEN, AND PAUSING MOMENTARILY AT EACH STATION FOR LOADING AND FIRING FUNCTIONS. A MAGAZINE IS MOUNTED AT EACH LOADING STATION FOR REGISTRY WITH THE CHAMBERS WHEN RESPECTIVELY INDEXED THEREAT, AND SOLENOID ACTUATED GATES CONTROL THE PASSAGES OF THE ROUNDS FROM THE MAGAZINES TO THE CHAMBERS. AN ELECTRICAL SYSTEM, THROUGH A MICROSWITCH ACTUATED BY THE GENEVA MOVEMENT, CONTROLS THE OPERATION OF THE GATES SO AS TO FEED THE ROUNDS FROM ONE MAGAZINE TO THE INDEXED ONE OF THE CHAMBERS WHEN THE DRUM IS ROTATED IN ONE DIRECTION AND FROM THE OTHER MAGAZINE TO THE INDEXED CHAMBERS WHEN THE DRUM IS ROTATED IN THE OPPOSITE DIRECTION.

Description

Sept. 28, 1971 H. H WIESE 3,608,424

FEEDING MECHANISM OF AN AUTOMATIC CANNON FOR FIRING CASELESS AMMUNITION 6 Sheets-Sheet 1 Filed Oct. 8, 1969 @Q/ Sa on 5235 1528 I INVENTOR ATTORNEYS H. WIESE 3,608,424 FEEDING MECHANISM OF AN AUTOMATIC CANNON 6 Sheets-Sheet 2 I om mm I FOR FIRING CASELESS AMMUNITION m 4 V. g i W INVENTOR HnrnliHWiese BY WA/ u Sept. 28, 1971 Filed 001;. s, 1969 Q ow om IE 3 1 Q k//////////V///A7/////////// 7/////// /fl/ .V v V, r LP |UH|vL|| m ow Ev mv 9 g ATTORNEYS Sept. 28, 1971 FEEDING Filed Oct. 8, 1969 H. H. WIESE MECHANISM OF AN AUTOMATIC CANNO ING CASELESS AMMU Sept. 28, 1971 H. H. WIESE 3,608,424

FEEDING MECHANISM OF AN AUTOMATIC CANNON FOR FIRING CASELESS AMMUNITION Filed Oct. 8, 1969 6 Sheets-Sheet L INVENTOR H111 U111 H Wi e a 2 ATTORNEYS Sept. 28, 1971 H. WlESE 3,

FEEDING MECH SM OF AN AUTOMATIC CANNON FOR FIRING CASELESS AMMUNITION Filed Oct; 8, 1969 6 Sheets-Sheet 5 VENTOR H111 H Wiese ATTORNEY Sept. 28, 1971 H. H. WIESE 3,608,424

FEEDING MECHANISM OF AN AUTOMATIC CANNON FOR FIRING CASELESS AMMUNITION Filed Oct. 8, 1969 6 Sheets-Sheet 6 INVENTOR ATTORNEYS U ited States Patent 3,608,424 Patented Sept. 28, 1971 3,608,424 FEEDING MECHANISM OF AN AUTOMATIC CANNON FOR FIRING CASELESS AMMUNITION Harold H. Wiese, Davenport, Iowa, assignor to the United States of America as represented by the Secretary of the Army Filed Oct. 8, 1969, Ser. No. 864,849 Int. Cl. F41d 7/04 US. Cl. 89-13R 11 Claims ABSTRACT OF THE DISCLOSURE The feeding mechanism of an automatic cannon includes a four-chamber drum which is selectively driven in opposite directions by a reversible electric motor. A Geneva movement is operationally disposed between the motor and drum to provide intermittent rotation thereof for successively rotating each of the chambers to four stations including a firing station, an ejection station, and two loading stations oppositely disposed therebetween, and pausing momentarily at each station for loading and firing functions. A magazine is mounted at each loading station for registry with the chambers when respectively indexed thereat, and solenoid actuated gates control the passages of the rounds from the magazines to the chambers. An electrical system, through a micros-witch actuated by the Geneva movement, controls the operation of the gates so as to feed the rounds from one magazine to the indexed one of the chambers when the drum is rotated in one direction and from the other magazine to the indexed chambers when the drum is rotated in the opposite direction.

The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to me of any royalty thereon.

BACKGROUND OF THE INVENTION This invention relates to automatic cannons for firing caseless rounds and pertains more particularly to the feeding mechanism thereof, which is electrically operated and controlled.

In the long history of firearm development, the invention of the cartridge, whereby the projectile, propellant and primer are all contained in a metallic case to provide for quick and ready handling, was a major milestone in the art. Cartridges, however, create inherent problems in the design of automatic guns because, after a cartridge is discharged, meticulously machined and carefully timed means must be p-rovided in the weapon for extracting the fired case from the barrel and ejecting it from the weapon before another cartridge can be chambered for discharge. Finally, the fired case must be disposed of which raises perplexing problems which are critical where the weapon is used in an inclosed space of limited proportions.

The obvious solution to these problems is to eliminate the case and provide a round of ammunition in which all elements, except for the projectile, are completely combustible upon discharge so that there are no residual parts which have to be considered in the weapon designs.

SUMMARY OF THE INVENTION The development of caseless ammunition is opening new fields in weapon designs. Along these lines, it is a principal object of this invention to provide for cannons adapted for firing caseless ammunition a feeding mechanism which is distinguished for its simplicity and which provides for automatic guns a feeding mechanism whereby ammunition can be fed from one of two magazines merely by flipping a switch. When both magazine contain the same type of ammunition, one is readily available as a reserve, to increase the firepower available to the troops and when the magazines contain ammunition of different military characteristics, feeding from them may be quickly and readily changed to broaden the firepower available to the troops.

It is a more specific object of this invention to provide for automatic cannons a feeding mechanism which comprises a four-chamber drum selectively driven in opposite directions by a reversible electric motor, and a Geneva movement operationally disposed between the motor and drum for intermittent rotation thereof so as to successively rotate each of the chambers to four stations and momentarily pause at each for loading and firing purposes. Two of the stations are loading stations, which are located on opposite sides of the firing station, and mounted at each of the loading stations is a magazine which has registry with successive ones of the chambers when indexed therewith. Solenoid actuated gates control passage of the rounds from the magazines to the drum chambers and an electrical system, through a micro-switch actuated by the Geneva movement, controls the operation of the gates so that the rounds are fed from one magazine to the indexed one of the chambers when the drum is rotated in one direction and from the other magazine to the indexed one of the chambers when the drum is rotated in the opposite direction.

Further objects and advantages of the invention will be apparent from the following specification and the accompanying drawings which are for the purpose of illustration only in which:

FIG. 1 is an assembly view, shown partially in perspective and partially schematically, of a cannon for firing caseless ammunition and which incorporates the feeding mechanism of this invention;

FIG. 2 is a longitudinally cross-sectioned view of the drum and gear reduction units of the cannon;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 2;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 2 looking towards the breech end of the cannon;

FIG. 6 is a sectional view taken along line 66 of FIG. 2 looking towards the front end of the cannon;

FIG. 7 is a partially exploded view of one of the camgear arrangements for actuating the gates;

FIG. 8 is a sectional view taken along line 8-8 of FIG. 6;

FIG. 9 is a sectional view taken along line 99 of FIG. 8;

FIG. 10 is a sectional view taken along line 10-10 of FIG. 6', and

FIG. 11 is a schematic view of the electrical circults at the control panel.

Shown in the figures is an automatic cannon 12 for firing rounds 14 of caseless ammunition, which include a primer 15 disposed at the rear end of each thereof. Cannon 12 comprises a housing 16 which encloses a drive unit 18 and a chambered drum 20 driven thereby through a Geneva movement 22; a head assembly 24 including an integral support for barrel 26; magazine means 28 ineluding a spring actuated magazine 30 and a pneumatically actuated magazine 32; and an electrical control system 34.

Drive unit 18 comprises a reversible electrical motor 36 which is connected electrically to electrical system 34 for rotation at variable speeds in opposite directions and is connected mechanically to a gear reduction unit 38. Such gear reduction unit 38 is provided with an output shaft 40 which extends forwardly from case 42 for the gear reduction unit in axial alignment with the bore of barrel 26. Mounted on the extending portion of drive shaft 40 so as to be rotated thereby is a crank wheel 44 which is a part of Geneva movement 22. A pair of crankpins 46 are fixed to crank wheel 44 so as to be diametrically disposed thereon and equally spaced from the axis thereof. Axially mounted on the front face of crank wheel 44 between crankpins 46, as shown in FIGS. 3 and 4, is a locking wheel 48 which includes a pair of diametrically opposed convex sections 50 of the same radius, and a pair of concave sections 52 having the same radius as the convex sections and symmetrically located therebetween. Geneva movement 22 also includes a star wheel 54 which is mounted on the rearwardly extending section of axle 56 which rotatingly mounts drum 20 in houssing 16. As especially shown in FIG. 3, star wheel 56 is provided with four symmetrically spaced radial channels 58 each being arranged to receive one of the crankpins 46 during rotation of crank wheel 44 to transfer rotation thereof to the star wheel, and symmetrically formed between pairs of the channels are four arcuate recesses 60. Such recesses 60 are arranged to matingly receive one of the convex sections 50 when both crankpins 46 are free of all channels 58, as shown in FIG. 3. Thus, when one of the convex sections '50 is received by one of the recesses 60, star wheel 54 is held thereby against rotation. As crank wheel 44 continues to turn relative to star wheel 54, one of the crankpins 46 enters the one of the channels 58 aligned therewith and the locking one of the convex surfaces 50 is moved out of the cooperating one of the recesses 60 so that the continued rotation of the crank wheel moves such crankpin against the side of the engaged channel to transfer rotation of the crank wheel to the star wheel. Star wheel 54 is rotated thereby 90 which aligns the opposite one of the crankpins 46 with the next one of the channels 58 and the opposite convex section 50 into the next recess 60 so that drum 20 is rotated in sequential periods of rotation and non-rotation.

Drum 20 is provided with four symmetrically arranged chambers 62 which are respectively designed to receive a round 14 from the front end of the drum. Round 14 is tapered towards the front and rear, as shown in FIG. 2, and the rear ends of chambers 62 are tapered to conform to the configuration of the rear end of the round and thereby secure it against angular displacement. Through the operation of Geneva movement 22, drum 20 is rotated so that each of the chambers 62 is rotated to four stations during one revolution of the drum and is momentarily held stationary at each of the stations when located thereat. Referring to FIG. 6, which is a section looking towards the front end of cannon 12 from the rear, station A is shown at the top position, station B at the right thereof, station C at the bottom position, and station D at the left of station A. When one of the chambers 62 is indexed at station A it is in alignment with barrel 26 and round 14 in the chamber is in position to be fired. Stations B and D are the loading stations where rounds 14 are fed into chambers 62 and station C is the ejection station.

Provided in housing 16 approximately midway the length thereof and integral therewith, as shown in FIG. 2, is a breech plate 64 which is normal to the longitudinal axis thereof. Breech plate 64 mounts a sequentially actuated firing pin 66 in registry with station A for discharging round 14 when located thereat. Such firing pin 66 and its operation is not part of this invention. Located in breech plate 64 in registry with station C is a nozzle 68 which is connected by conduit means 70 to a source of pneumatic pressure 72, as shown in FIG. I, for blowing by means of compressed air a dud from drum 20 in event one of rounds Ltl: fails to fire and for cooling the chambers when indexed ereat.

Head assembly 24 includes a circular plate 74 which is fixed to the front end of housing 16 to provide the front for the ejection of a dud when blown from drum 20 by pneumatic pressure and for escape of the compressed air when cooling chamber 62.

Sockets

78 and 80 are each adapted to receive the inner feeding end of either

magazine

30 or 32. Mounted to the front of plate 74 contiguous to each of the

sockets

78 and 80 is a latch 84 which cooperates with a notch 85 disposed adjacent the feeding ends of both

magazines

30 and 32 as shown in FIG. 9, for releasably holding them assembled to housing 16.

Mounted to the rear face of plate 74 at each of the

sockets

78 and 80 is a gate 86 for controlling the passage of rounds 14 from

magazines

30 and 32 to chambers 62. Each gate 86 includes a rotary cam 88 comprising a sleeve 90, which is journaled in the associated one of the

sockets

78 and 80. The inside diameter of sleeve 90 is slightly larger than the large diameter of round 14 so that the round may pass smoothly through rotary cam 88 into the aligned chamber 62. A flange 92 extends more than 240 but less than 360 around sleeve 90 at the front end thereof. Spaced 120 apart in flange 92 are three cam slots 94 having a function which will be explained hereinafter. Flange 92 is rotatingly received by a substantially cylindrical recess 96 which is formed in the rear face of plate 74. Recess 96 forms a circular wall 98, which is concentric With sleeve 90 and has a radius substantially the same as that of the outside circumference of flange 92, and a plannar wall 100 which is parallel to the outside face of plate 74. Extending into recess 96 is a tang 102 which is received by a clearance 104 in flange 92 formed to permit limited rotational displacement of rotary cam 88 relative to plate 74. Rotary cam 88 is releasably held in plate 74 by a snap ring 106 which is received by a mating channel 108 in circular wall 98.

Each rotary cam 88 is rotated by a torque producing solenoid 110 that mounts a gear sector 112 which has meshing engagement with mating teeth 114 formed around the outside circumference of flange 92. Rotation of rotary cam 88 is converted, as hereinafter described, to translational displacement of a set of three fingers 116 which are slidingly mounted in a plate 74 for radial displacement respective to the

related socket

78 or 80. Fingers 116 are radially displaceable between an extended position wherein the inner ends project into opening 120 of sleeve 90 and a retracted position wherein the ends are withdrawn therefrom. When fingers 116 are in their extended positions, the related gate 86 is closed and rounds 14 are blocked from passing thereby from the related

magazine

30 or 32 into drum 20. When fingers 116 are in their retracted positions the related gate 86 is open and rounds 14 may pass thereby into drum 20. Fingers 116 are radially displaced by rotary cam 88 by means of a pin type follower 126 which extends from each of the fingers into a related one of the cam slots 94.

A coiled torsion spring 128 is mounted on each of the solenoids 110 so as normally to bias gear sectors 112 thereon for rotation in a direction to actuate fingers 116 to their extended positions. When solenoids 110 are energized, gear sectors 112 are rotated against the bias of springs 128 to displace fingers 116 to their retracted positions.

Sequential operation of solenoids 110 in the operating cycle of cannon 12 is provided by electrical system 3 4 that also includes a microswitch 130 which, as shown in FIG. 4, is mounted on the front face of case 42 so that roller 132 of the microswitch has rolling contact with stepped circumference 134 of crank wheel 44. Circumference 134 is designed for cooperation with microswitch 130 so that during that portion of the rotation of crank wheel 44 when drum 20 is being rotated thereby the microswitch is open and solenoids 110 are consequentially mechanically energized by the related spring 128 to hold fingers 116 in their extended positions, closing the related gate 86, and when the drum is at rest the microswitch is closed and a selected solenoid is electrically energized,

Thus, gear sector 112 of the energized solenoid 110 is rotated to actuate the related fingers 116 to their retracted positions, opening the respective gate 86.

Electrical system 34 also includes a panel 136 for selectively controlling the operation of cannon 12 and wiring circuits 138 which electrically connect motor 36 and solenoids 110 through the panel to sources of constant and variable voltage current shown at 139 and 141 respectrvely. Constant voltage current is used, as seen in FIGS. 1 and ll, to energize solenoids 110, a relay 140 which connects motor 36 to source of variable voltage 141 for dl'lVlIlg drum 120 in a clockwise rotation, and a similar relay 142 which connects the motor to the source of variable voltage current so as to drive the drum in counterclockwise rotation. With the voltage current which energizes motor 36..being variable the firing rate of cannon 12 can be regulated thereby.

Relay 140, when energized, also connects source of constant voltage current 139 through microswitch 130 to the solenoid 110 which is associated with station D. Relay 142, when energized, connects source of constant voltage current 139 through microswitch 130 to the other solenoid 110 which is associated with station B. The constant voltage current is controlled by an on-otf switch 144 and in series therewith is a push button firing switch 146 which is disposed between the on-off switch and a toggle-type selector switch 148 which controls the application of the constant voltage current to relays 140 to 142. Selector switch 148 also serves to introduce into the circuit to the solenoid 110 which is associated with station D a rounds counter 150 and into the circuit to the other solenoid which is associated with station B a rounds counter 152 to register the number of rounds 14 fired from the associated ones of the magazines at these stations.

OPERATION Provided for cannon 12 are two types of magazines. One, magazine 32, comprises a flexible tubular case 154 into which rounds 14 are inserted in tandem arrangement with the rear ends thereof being inserted facing the inner end of the magazine so that when the rounds are transferred to chambers 62 primers 15 can be acted upon by firing pin 66 when the chambers are indexed at station A. The inner end of magazine 32 is then inserted into the selected

socket

78 or 80 and secured therein by latch 84. The opposite end of magazine 32 is attached to source of pneumatic pressure 72, as shown in FIG. 1. The inside diameter of case 154 is arranged to be slightly larger than the largest diameter of round 14 so that the pneumatic pressure is applied against each of the rounds to facilitate the displacement thereof along the case. Rounds 14 are prevented from passing into the aligned chamber 62 because both gates 86 are closed until one of the solenoids 110 is electrically energized when firing is commenced. Among the advantages of magnazine 32 are the elimination of a follower, and the flexibility of case 154 whereby it may be twisted in any direction as long as the radius of any resulting arc is greater than that of the outside surface of round 14 along the longitudinal section thereof. Magazine 30, in which mechanical force is applied to rounds 14 by a spring-pressed follower, can be utilized when pneumatic pressure is not available.

Changing the feed of cannon 12 from one of the two magazines mounted thereto to the other is easily effected by flicking selector switch 148. Thus, when the magazines are loaded with rounds 14 having different military characteristics, such as point and area firepower capabilities, changing the firepower produced by cannon 12 is easily effected. Also, when the same type rounds 14 are loaded into both magazines, a reserve supply of the rounds is readily available and one of the magazines can be reloaded while the other is being used.

With magazines 30 and/ or 32 latched in

sockets

78 and 80, cannon 12 is ready to be fired when On-Off switch 144 is displaced to the On position. Selector switch 148 is indexed in either the L position, for firing rounds 14 in the left one of the magazine means 28 at station D, or the R position, for firing the rounds in the right one thereof at station B. To fire cannon 12, push button switch 146 is pressed in. For instance, if selector switch 148 is indexed in the R position and push button switch 146 is pressed in, the circuit is closed through the selector switch to relay 142 which is thereby actuated to energize motor 36 for rotating drum 20 in a counterclockwise direction and to close the circuit through microswitch to the solenoid 110 which is associated with gate 86 at station B. Thus, motor 36 is energized to rotate crankwheel 44. When stepped circumference 134 of crankwheel 44 is rotated to close microswitch 130, and drum is stationary, the related solenoid 110 is energized to open the associated gate 86 by retracting fingers 116 thereof. This permits the displacement of the leading round 14 in the related magazine means 28 into the one of the chambers 62 which is indexed at station B. Before Geneva movement 22 acts to transfer rotation of drive unit 18 to drum 20, the continually rotating stepped circumference 134 of crank wheel 44 acts to deenergize the related solenoid 110 which permits the associated gate 86 to be closed and thereby retain the chambered round 14 in drum 20 and hold the remaining rounds in the magazine. During the following rotation period of drum 20, the chambered round 14 is carried to station A and fired by firing pin 66 during the sequential rest period by means which are not a part of this invention. At the same time, a round 14 is chambered in drum 20 as explained hereinbefore. If round 14 is carried to station A and fired by fiiring pin 66 D to station C where it is blown from drum 20 through ejection port 82 by the application of pneumatic pressure provided through nozzle 68. When the firing burst is to be stopped pressure is removed from switch 146 which opens the circuit to the selected solenoid 110 which is thereby deenergized so that spring 128 thereon instantly closes gate 86 to prevent any further rounds 14 from being transferred to chambers 62 even while drum 20 coasts to a stop.

When rounds 14 from the left one of the magazine means 28 are to be fired, selector switch 148 is indexed in the L position. Thus, when push button switch 146 is pressed for firing cannon 12, relay is energized to energize motor 36 for rotating drum 20 in a clockwise direction and to energize the solenoid 110 which controls gate 36 at D station.

I wish it to be understood that I do not desire to be limited to the exact details of the embodiment of the invention as described, for obvious modifications will occur to a person skilled in the art.

I claim:

1. In an automatic gun comprising a housing and a barrel mounted thereto, a mechanism for feeding rounds of ammunition to the barrel for discharge thereat comprising a drum rotatably mounted in the housing, a plurality of chambers respectively disposed in said drum for receiving said rounds for discharge, reversible motor means, means for converting continuous rotation of said motor means to intermittent rotation of said drum and for successively indexing said chambers at each of several stations including a firing station and a pair of loading stations located on opposite sides thereof and momentarily stopping thereat, a pair of magazines each adapted for holding a plurality of the rounds and for biasing the rounds towards an inner feeding end thereof, means for respectively mounting said pair of magazines to said housing at said pair of loading stations so that each has reglstry with successive ones of said chambers when indexed thereat, gate means controlling the passage of the rounds from said magazines to the ones of said chambers indexed therewith, and actuating means for displacing said gate means so as to open communication between one of said magazines and the ones of said chambers indexed therewith and closing communication between the other one of said magazines and the ones of said chambers indexed therewith when said drum is rotated in one direction and to open communication between the other one of said magazines and the ones of said chambers indexed therewith and closing communications between said one of said magazines and the ones of said chambers indexed therewith when said drum is rotated in the opposite direction, said actuating means including a Geneva movement operatively disposed between said motor means and said drum and comprising a crank wheel operationally connected to said motor means and a star wheel connected to said drum.

2. The invention as defined in claim 1 wherein at least one of said magazines includes a flexible tubular case for holding a supply of rounds, said case comprising an inner feeding end disposed for attachment to the housing at one of the loading stations, and another end attachable to a source of pneumatic pressure utilized for biasing said rounds in said case towards said drum, and said case having a diameter which is greater than the largest diameter of the rounds to permit application of the pneumatic pressure upon each thereof in said case.

3. The invention as defined in claim 1 wherein said drum is provided with four chambers symmetrically disposed therein and said Geneva movement operates to rotate said drum intermittently so that each of said four chambers is successively indexed at four stations including the firing station, the pair of loading stations and an ejection station disposed opposite the firing station and is momentarily stopped at each thereof.

4. The invention as defined in claim 1 wherein said means for mounting said pair of magazines to said housing comprises a socket disposed through a front cover thereof at each of the loading stations and each of said sockets being adapted for receiving the inner feeding end of said magazines, said gate means comprises a pair of gates respectively associated with said sockets, each of said gates comprising a plurality of fingers disposed around the associated ones of said sockets for radial displacement respective thereto between extended positions wherein the inner ends of said fingers extend into the associated one of said sockets to block passage of the rounds from the related one of said magazines and retracted positions wherein the inner ends of said fingers are located clear of the inner feeding end of the respective one of said magazines, a torque producing solenoid operationally associated with each of said gates, and cam means operationally disposed between each of said gates and the associated one of said solenoids for converting the torque thereof to radial displacement'of said fingers.

5. The invention as defined in claim 4 and including a nozzle connected by conduit means to a source of pneumatic pressure and directed into said chambers when indexed at the ejection station to cool the indexed one of said chambers and to blow therefrom a round not discharged at the firing station.

6. The invention as defined in claim 4 wherein said cam means comprises a rotary cam, a sleeve of said rotary cam journaled in the respective one of said sockets for rotation therein, a flange integrally mounted to said sleeve, a gear sector mounted to said solenoid for rotation thereby, teeth on said flange disposed for meshing engagement with said gear sector for transferring rotation thereof to said rotary cam, a pin follower extending from each of said fingers, and cam slots in said flange engaging said pin followers for converting rotation of said rotary cam to radial displacement of said fingers between the extended and retracted positions thereof.

7. The invention as defined in claim 4 wherein said means for actuating said gate means includes an electrical system responsive to intermittent actuation of said drum for energizing a selected one of said solenoids to actuate the related ones of said fingers to their retracted positions when said chambers are stopped at the related one of the loading stations, and mechanical means for actuating said fingers to their extended positions when said solenoids are deenergized.

8. The invention as defined in claim 4 wherein said means for actuating said gate means includes an electrical system arranged for actuating to the open position the one of said gate means preceding the firing station according to the direction of rotation of said drum when said chambers are stopped thereat.

9. The invention as defined in claim 4 wherein said means for actuating said gate means comprise an electrical system including said solenoids and means for energizing a selected one of said solenoids responsive to operation of said Geneva movement, and including mechanical means disposed in cooperation with said solenoids for actuating said gate means to the closed positions when said solenoids are not energized.

10. The invention as defined in claim 9 wherein said electrical system includes two relays, a fire control switch disposed for cooperation with a selector switch for completing an electrical circuit to one of said relays, electrical circuitry to energize said motor means for rotation in one direction when one of said relays selected by said selector switch is energized by said fire control switch and to also energize the one of said solenoids actuating the one of said gates located at the loading station preceding the firing station according to the direction of rotation of said drum, and to energize said motor means for rotation in the opposite direction and energize the other one of said solenoids when the other one of said relays is selected to be energized, and a microswitch disposed for cooperation with a stepped circumference of said crank wheel to control the circuit to the selected one of said solenoids so that the related one of said gates is closed during rotation of said drum and is open when said drum is stopped to index said chambers therein at said stations.

11. The invention as defined in claim 9 and including counter means arranged for actuation by said electrical system to separately record the number of the rounds fed from each of said magazines and discharged at the firing station.

References Cited UNITED STATES PATENTS 473,370

BENJAMIN A. BORCHELT, Primary Examiner S. C. BENTLEY, Assistant Examiner US. Cl. X.R.

8933 MC, 335 F, B C

4/1892 Thorp 42-60