US2456812A

US2456812A - Recoilless gun

Info

Publication number: US2456812A
Application number: US554820A
Authority: US
Inventors: Blacker Latham Valenti Stewart
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-05-04
Filing date: 1944-09-19
Publication date: 1948-12-21
Anticipated expiration: 1965-12-21

Description

Dec. 21, 1948.

| v. s. BLACKER REcoILLEss GUN 5 Sheets-Sheet 1 Filed Sept. 19, 1944 LATHIM VALENTIAIE STEWART BLIMKER I 8) Quiz 'r" 14 TTUR/VF S Dec. 21, 1948. L. v. s. B'LACKER BECOILLESS 'GUN Filed Sept. 19,' 1944 5 Sheets-Sheet 2 J na LATHAM VALENTINE sTewmisL z INVENTOA 5 Sheets-Sheet 5 L. V. S. BLACKER RECOILLESS GUN Dec. 21, 1948.

Filed Sept. 19, 1944 14 TTOR/VEL Q A LATHAM VALENTINE STEWART BLACKEQ Dec. 21, 1948. v. s. BLACKER RECOILLESS GUN 5 Sheets-Sheet 4 Filed Sept. 19, 1944 Patented Dec. 21, 1948 RECOILLESS GUN Latham Valentine Stewart Blacker, Fittleworth, Pulborough, England Application September 19, 1944, Serial No. 554,820

In Great Britain May 4, 1938 11 Claims. 1

This invention relates to recoilless guns.

An important object of my invention is to provide a gun in which the recoil forces generated upon the discharge of a propellant cartridge are largely absorbed and are utilized for recockin the gun.

Another object of my invention is to provide means for accurately locating a projectile in position in a gun so that a moving striker can enter a narrow tube in the tail of the projectile and discharge a propellant charge at the end of the tube.

A further object of my invention is to provide an improved form of trigger andautomatic cocking mechanism.

Yet another object of my invention is to provide an improved gun with a magazine for projectiles and with means by which the feed to the magazine and the recocking are wholly automatic.

Further objects of my invention will appear in the course of the following description when read in conjunction with the annexed drawings, in which:

Figure 1 is a central longitudinal section through one form of gun with the parts in the cocked position;

Figure 2 is a plan of the Figure 1 gun;

Figure 3 is a section similar to Figure 1 at the moment of discharge of the cartridge;

Figure 3a is a longitudinal sectional view of a projectile with a fragmentary showing of the striker;

Figure 4 is a longitudinal section through a modified form of trigger mechanism suitable for use in a gun of the kind shown in Figures 1 to 3;

Figure 5 is a central longitudinal section through a larger gun mounted in a tank;

Figure 6 is a section through the trigger mechanism of the gun shown in Figure 5;

Figure 7 is a side view of a magazine gun;

Figure 8 is a longitudinal horizontal section through the gun shown in Figure '7, with the parts in the cooked position;

Figure 9 is a section similar to Figure 8 at the moment of discharge of the propellant cartridge; and

\ Figure 10 is a section on the line X-X in Figure 7.

The gun shown in Figures 1 to 3 compr ises a cylindrical casing l which carries at its forward end a cap 2 around which a ring 3 is fixed. The gun is designed to project a projectile l, and an open-topped loading trough 5 for the projectile 4 hasa cylindrical rearward end 6 which fits over vided at the inner end of the tail tube 1.

the ring 3. The projectile has a tube 1 located partly inside and partly outside its tail end and carrying a drum tail 8, and a cartridge 9 is pro- In order to project the projectile it is necessary to discharge this cartridge 9 and for this purpose a movable striker I0 is arranged to fly forward into and through the tail tube 1. The nose of the striker forms a firing pin which, on reaching the cartridge, enters the primer 9b of the cartridge 9, striker I0 thereby serving as a firing pin "carrier. The forward portion of the projectile 4 will include a grenade or the like 4a.

The striker Ill forms part of a heavy dynamic mass, the momentum of which is utilized to absorb a substantial part of the recoil forces generated on discharge of the propellant cartridge 9. This dynamic mass largely consists of a heavy sleeve II the bore of which is reduced in diameter and internally screw-threaded to receive the threaded end l2 of the striker In, which has a flange l3 which abuts against the shoulder formed by the reduced part of the bore in sleeve II. A pistonlike head or disc l4 constituting a cocking shoulder is screwed on to the sleeve l I. Head I4 also forms part of the above-mentioned dynamic mass. The sleeve H can slide within a cocking tube 16 which is welded to a back plate or butt H. An outer cup 18 is also welded to the back plate and surrounds .an inner cup l9 which is welded to the casing l. A spring 2i! surrounds the cocking tube l6, bearing at one end on the inner cup l9 and at the other end on the pistonlike head l4, and being surrounded by a skirt i5 which extends rearwardly from the disc l4 and guides and steadies-the spring in operation.

In the cocked position shown in Figure 1 the dynamic mass including striker I0, sleeve H and skirted disc I4 is held against the action of the spring 20 by a control mechanism comprising a scar 2| which engages the forward edge of the disc I! and is pivotally mounted on a pin 28 which is fixed in a housing 23. This sear is urged into the latching position by a compression spring 22 also mounted within housing 23. The trigger 24 is pivotally mounted on a pin 25 extending across the housing 23, and the finger piece of the trigger projects through an opening I23 in the housing 23. The trigger is connected by a pivot pin I24 to a disconnector 26, the forward end of which bears on a nose 21 formed on the sear 2|. When the trigger 24 is pressed the disconnector 26 rocks the sear 2| so that the dynamic mass is released and driven rapidly forward by the spring 20 into the position shown in Figure 3. The

striker ||I traveling up the tail tube I of the projectile to discharge the cartridge 9 so that the projectile is projected. On the discharge of the cartridge 9 its rear portion 9a is driven backwards into the tail tube 1 and seals the explosion gases. It is important that on discharge the rear part of the cartridge should expand radially and completely obturate the tail tube. This part 9a of the cartridge acts as a piston which bears directly on the striker l0, driving the dynamic mass backwards. In this manner, not only are the recoil forces absorbed but they are directly and consistently applied to the dynamic mass to bring about automatic recocking.

For recocking purposes it is essential that the sear 2| should be allowed to return to the cocking position freely and immediately. As this might be prevented if the nose of the disconnector 26 could remain in engagement with the nose 2'! of the sear, a fixed pin 29 is provided to cooperate with a sloping surface on the disconnector so that as the trigger 24 is pressed completely backwards the disconnector after rocking the sear is forced downwards away from the nose 21. If the trigger 24 remains pressed during the whole of the recoil of the dynamic mass the sear 2| will act independently of the trigger and disconnector and latch the disc I4 in the cocked position shown in Figure 1 when the dynamic mass recoils under the action of the recoil forces. If the trigger be released before the dynamic mass returns, the disconnector 26 will be moved outwards by the engagement of the rearward edge of the disc l4 with a forked nose 30, the two arms of which are rigid with the disconnector and lie one on each side of the sear 2|. Immediately disc H has passed over this nose the disconnector and trigger will be returned to the ready-to-fire position by means of a spring 3| anchored at one end to the disconnector and at the other end to the casing I. In the absence of the forked nose 30 the user of the weapon, by releasing the trigger during the movement of the dynamic mass, might cause the nose of the disconnector to re-engage with the sear 2| prematurely.

A hand grip 32 and a trigger guard 83 of the usual kind are provided, as also are a foresight 34 on the loading trough and a backsight 35 on the casing I.

It is of course necessary to be able to cook the gun initially even though it is self-cocking whenever it is fired. For this purpose the assembly formed by the back plate l1. outer cup l8 and cocking tube element It is made disconnectible, the outer cup l8 being formed with two bayonet slots 36 entered by studs 31 carried by the inner cup I9. When the gun is to be cocked initially the back plate assembly is turned through 90 so that it is unlocked as a whole and can slide rearwardly relatively to the studs 31. The back plate assembly is then pulled back, and this results in an inner flange 38 at the end of the cocking tube coming into contact with a flange 39 at the end of the sleeve so that the latter is pulled backwards against the spring 20 until the head l4 engages the sear 2| and the dynamic mass is cocked, i. e., held by sear 2|. The back plate assembly is thereafter free to be pushed home and relocked by rotation through 90 when the locking studs 31 have entered the slots 38.

It will be observed that the sleeve l I is hollow, and accordingly in the forward movement can pass over a guide tube 40 which projects rearwardly from the end cap 2 and serves to guide the striker III. This telescoping of the sleeve and the guide tube allows of a very long recoiling movement in relation to the overall dimensions of the weapon and so allows the recoil forces to be absorbed relatively gradually.

When the striker l0 travels rapidly up the tail tube I of the projectile, air is compressed in the tail tube with the result that there is an immediate force exerted on the projectile before the propellant cartridge is discharged. If the projectile were simply placed in the loading trough without being restrained in any way it might move forward under the action of this force and the striker might then fall to discharge the cartridge. To prevent this the projectile is provided with a collar 4| which is united to the end of the tail tube by means of a light soldered joint or equivalent connection which will easily break or shear or pull OK when the propellant cartridge 9 is discharged. This collar 4| engages behind ribs 42 which are made rigid with the cap 2 and this engagement serves to hold the projectile in position until the cartridge is discharged.

It is desirable that the projectile should be loaded transversely rather than axially, since in this way the risk of the loader placing hishand in the path of the striker and so being injured if the weapon is accidentally fired as minimised. With transverse loading the striker must have a long enough recoil movement to be clear of the loading trough in the cooked position, so means must be provided for locating the projectile accurately in position relatively to the striker and the guide tube 40. Registration in a vertical direction is ensured because the drum 8 of the projectile rests on the bottom of the loading trough 5, but naturally to enable projectiles to be loaded quickly there must be a relatively large clearance between the walls of the trough and the projectiles. The ribs 42 serve the useful additional function of guiding the tail end of the projectile during the loading and locating the tail tube laterally in exact register with the end of the guide tube 40.

When the cartridge has been discharged and the connections between the collar 4| and the end of the tail tube 1 is broken the collar 4| falls out of the loading trough through an opening 43, as also does the rear portion of the fired cartridge.

Figure 4 shows a modified control mechanism. In this case a disconnector in tension is used and is shown at 44. It has a hooked part 45 which engages behind a nose on a sear 2|, which is subjected to the action of a spring 22 and is pivoted on a pin 28'. The disconnector, which has a hump 46 which is engaged by the disc |4 during cocking, is not directly pivoted to the trigger 24 but by a pin I44 to a lever 41 which is itself connected by a square pin I45 to the trigger and which also carries a pin I46 to which a spring 48 is anchored, the other end of the spring being anchored to the disconnector 44. It will be observed that whereas in the construction shown in Figure 1 the disconnector and sear are at the same point along the gun, in the modification shown in Figure 4 they are at different points so the disconnector does not have to be forked to embrace the sear. To fire the weapon with this modified trigger mechanism the trigger 24 is pulled, the action of the operators finger causing the trigger to rock clockwise, the link 41 rocking clockwise with the trigger. As a result the disconnector 44 is pulled bodily towards the muzzle end of the gun and the hook 45 causes the sear 2| to rock anti-clockwise uritil the disc i4 is released. On the return movement the hump 46 is forced downwards until the disc I4 has passed over it, so that even if the trigger is released during the return of the dynamic mass the hook 45 will not re-engage the sear 2I' prematurely.

The gun shown in Figure is larger than that of Figures 1 to 3 and is intended to be mounted in a tank or other self-propelled vehicle. It is shown in position inside a tank, part of the armour of which is shown at 50. The gun as a whole is carried by a mantlet 5I, which is mounted on trunnions 52 fixed inside the tank. The mantlet includes a support 53 to which an end cap 54 rigid with the casing 55 of the weapon is bolted. Fixed within the end cap 54 is a guide tube 56 which receives a large slidin member or bolt 51 from which the striker 58 projects forward. The sliding member 51 is secured to a skirt-like tube 59 which receives an actuating spring 60, the other end of which bears against a rear end cap 6I. The tube 59, striker 58 and sliding member 51 form a large dynamic mass capable of absorbing the greater recoil forces generated upon the discharge of the larger projectile fired by this gun. At the forward end of the guide tube 56 there is a plate 62 to which a loading trou h 63 is bolted and with which a guide tube 64 for the striker 58 is made rigid. The guide tube 56 passes through an opening 65 in the armour of the tank and protection against the passage of bullets through this opening is given by the mantlet 5I The control mechanism is somewhat different in this gun and is shown in detail in Figure 6. There are two sears 66 and 61 which engage the forward end of the sliding member 51 in the cocked position. Both sears are in a dust-proof casing I13. The nose 13a of a disconnector 13 bears against the tail of the sear 61. This disconnector is pivotally connected by a pivot pin I19 (which extends across the casing I13) to an arm I80 which in turn is rigidly connected to a trigger 14 by a pin I8I which extends through the wall of the casing I13 and terminates outside the casing in a square end which engages a square hole in the trigger. The disconnector is subjected to the at one end to the disconnector and at the other end to the tube 56 at I18. When the lower end of the trigger 14 is pulled back (to the left in Figure 6), the disconnector 13 is pushed forward, i. e., to the right, and its nose 13a pushes against the sear 61, causing the latter to rock anticlockwise to move clear of 51. The scar 61 is connected rigidly to an arm I14 by the square end of a pin I15. Arm I14 is outside the casing I13 and is pivotally connected to a link 69 by a pin I69. As the arm I14 rocks with the sear, the

link 69 is pulled and turns a crank wheel to which it is connected by a pin I82. A second link 68 is pivoted to the crank wheel by a pin I83 and also to an arm I16 by a pin I84. This arm I16 is rigidly connected by the square end of a pin I11 to the sear 66. When the crank wheel 10 is turned by the pull on the link '69 the link 68 is pushed and rocks the arm I16 with the result that the sear 66 also moves clear of 51. The two sears are subjected to the action of springs H and 12, respectively. The springs are very diagrammatically shown as mounted in small housings. A pin is provided for the same purpose as the pin 29 in Figure 1. During the recoil movement, the sliding member 51 bears on the disconnector 13 so that only when the member 51 has cleared the disconnector is it possible for the tail of the action of a tension spring I85 which is anchored disconnector once more to engage the tail of the sear 13.

The gun shown in Figures 5 and 6 is too large to be cooked by hand initially. Accordingly a cooking winch 16 may be provided in the tank and when the gun is to be cooked a screwthreaded bar 11 carried on the end of a wire rope 18 attached to the winch is screwed into a threaded socket 19 formed in the end of the sliding member 51. The whole sliding nicmber and the parts associated with it are then pulled back into the cooked position by turning the handle of the winch.

In the gun shown in Figures 7 to 10 there is a heavy end plate 8I which carries a member"82 by which the whole gun may be pivotally secured to a base plate. In this case the dynamic mass is composed of a heavy sliding plate 83, a tube 84 closed by an end cap 85 from which a striker 86 projects forwardly and two tubes 81 fixed in the plate 83. These tubes 81 slide over fixed tubes 88 which surround fixed rods 89. Two actuating springs are provided, each surrounding one of the rods 89 within the corresponding tube 90 and bearing at its forward end on the closed forward end of the corresponding tube 81.

This gun is of the magazine type and it includes a trough 9I into which projectiles 92 are loaded so that they tend to move vertically downwards in the trough with their axes horizontal. The trough 9I is carried by the rods 89 which project forwards through the ends of the tubes 81 and enter a support 93 which is also fixed to the base plate by means not shown. The lower most projectile rests on the bottom of the trough 9| and the projectile next above it is held by two pairs of pivotally mounted feed pawls or

jaws

94 and 95 and 96 and 91 respectively. The

pawls

94 and 96 are keyed to a shaft 98 and the pawls 95 and 91 are keyed to a similar parallel shaft 99. These shafts are mounted in brackets IIO carried by the trough 9|. The

pawls

94 and 95 are interconnected by a linkage comprising a connecting rod I00 and two arms IOI and I02, each connected at one end to the connecting rod I00. These arms IN and I02 are respectively fixed to the shafts 98 and 99, so that when the one shaft rocks the other must rock in the opposite direction. There are two such linkages, one at each end of the pair of shafts 98 and 99. The shaft 98 carries a cam I03 which lies in the path of a finger I04 pivotally mounted at I05 on an extension I06 of the tube 88. The finger I04 can rock anti-clockwise against a spring I01 but is prevented from moving in a clockwise direction beyond the position shown in Figure 7 by an abutment I08 on the extension I06. When the whole dynamic mass moves forward the finger I04 strikes the rearward end of the cam I03 and rocks against the action of the spring I01 so that it is carried under the cam. Directly it clears the cam it is restored by the spring to the vertical position. On the return movement of the dynamic mass the back of the finger I04 bears on the inclined surface of the cam I93 and rocks it and the shaft 98 clockwise as seen in Figure 10. In consequence the

pawls

94 and 96 are rocked clockwise and the pawls 95 and 91 anti-clockwise and the prof ctile which they previously supported descends to the bottom of the trough 9|. All these rocked parts are restored to their initial position by the action of springs I09 directly the bomb has moved downwards out of the jaws, so that the next projectile is caught by and retained in the jaws.

The rearward end of the trough Si is provided with ribs Ill similar to the ribs 42 shown in Figures 1 to 3.

The trigger mechanism of the gun of Figures '7 to is not shown and may work on the same principle as those shown in Figures 1, 3, 4 and 6.

I claim:

1. In combination, a projectile and gun, the projectile being provided with an axial bore open at its rearward end, a propellant cartridge positioned in the bore in advance of said rearward end, said cartridge including an obturator portion movable along said bore and arranged to form a gas seal therein, the gun including a casing, a heavy dynamic mass including a forwardly extending firing pin, means for driving said mass toward the forward end of said casing, sear means for holding said mass against the action of said driving means, trigger means to operate said sear means to release position. means to support the projectile with its propellant cartridge in the path of movement of said firing pin, said firing pln having sufiicient length to extend into the projectile recess and detonate the propellant cartridge when said mass is moved forward, whereby detonation of said cartridge will drive said obturator portion of the projectile propellant cartridge rearwardly in the projectile bore and in gas-sealing relation to the bore to thereby move said mass rearwardly with respect to said casing, said mass and driving means therefor bein sufliciently heavy that the momentum of said mass will substantially absorb recoil resulting from discharge of the projectile cartridge.

2. The combination described in claim 1, including means to move the sear means to holding position with respect to the dynamic mass upon recoil of the latter.

3. The combination described in claim 1 including frangible means on the projectile to engage the projectile supporting means of the gun.

4. The combination described in claim 1 including a magazine positioned above the projectile supporting means, and means operated upon rearward movement of the dynamic mass to feed projectiles from said magazine to the projectile supporting means.

5. In a gun for projecting a projectile, which projectile is provided with an axial bore open at its rearward end with a propellant cartridge including a rearwardly movable obturating portion positioned in the bore in advance of said rearward end of the projectile, a casing, a heavy dynamic mass including a forwardly extending firing pin element movable therewith, said mass being reciprocable in said casing, means for driving said mass toward the forward end of said casing, sear means for holding said mass against the action of said driving means, trigger means to operate said sear means to release position, projectile supporting means beyond the forward end of asid casing adapted to hold the projectile substantially stationary during the forward travel of said mass and until the propellant cartridge is discharged, said firing pin element having sufficient length forwardly of said mass that when said mass is moved forwardly the forward end of said element will extend past the forward end of said casing and into the projectile recess so as to engage the projectile propellant cartridge, whereby discharge of the propellant cartridge will result in creation of explosive gases adapted to be primarily effective in the projectile recess so as to drive the obturating portion of the cartridge against said firing pin element, said mass and the driving means therefor being sufficiently heavy that the momentum of said mass will substantially absorb the recoil resulting from discharge of the projectile cartridge.

6. The combination described in claim 5, including means to move the sear means to holding position with respect to the dynamic mass upon recoil of the latter.

7. A gun of the character described in claim 5 including a magazine positioned above the projectile supporting means, and means operated upon rearward movement of the dynamic mass to feed projectiles from said magazine to the projectile supporting means.

8. The combination described in claim 1, including means to move said dynamic mass to a position for holding engagement by said sear means and independently of recoil action.

9. The combination described in claim 5, including means to move said dynamic mass to a position for holding engagement by said sear means and independently of recoil action.

10. The combination described in claim 1, including a tube element carried by said casing and engaged by said dynamic mass when the latter is in forward position. said tube element being movable rearwardly of the casing to move the dynamic mass into position to be held by said sear means.

11. The combination described in claim 5, including a tube element carried by said casing and engaged by said dynamic mass when the latter is in forward position, said tube element being movable rearwardly of the casing to move the dynamic mass into position to be held by said sear means.

LATHAM VALENTINE STEWART BLACKER.

REFERENCES CITED,

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

UNITED STATES PATENTS Number Name Date 1,326,763 Meinersmann Dec. 30, 1919 1,347,125 Schneider July 20, 1920 1,359,425 Piersantelli Nov. 16, 1920 1,440,333 Braunger Dec. 26, 1922 2,363,675 Johnson Nov. 28, 1944 FOREIGN PATENTS Number Country Date 106,141 Great Britain May 14, 1917 208,565 Switzerland May 1, 1940 308,475 Germany Sept. 21, 1920 405,159 Great Britain Feb. 1, 1934 412,580 Great Britain June 28, 1934