US1299139A

US1299139A - Firing mechanism of breech-loading guns.

Info

Publication number: US1299139A
Application number: US17611017A
Authority: US
Inventors: Arthur Trevor Dawson; George Thomas Buckham
Original assignee: Vickers Ltd
Current assignee: Vickers Ltd
Priority date: 1917-06-21
Filing date: 1917-06-21
Publication date: 1919-04-01
Anticipated expiration: 1936-04-01

Description

A. T. DAWSON & G. T. BUCKHAM. FIRING MECHANISM 0F BREACH LOADING GUNS.

APPLICATION FILED IUNE2I|19I7 Patented Apr. 1.1919.

A. T. DAWSON & 61T. ucKHAM. FIRING MECHANISM 0F BREACH LOADiNG GUNS.

APPLICATION FIVLED JUNE 2l. 1917.

.Illl

Patented Apr. 1*, 1919.

A. T. DAWSON & 64T. BUCKHAM.

FIRING MECHANISM 0F BHEACH LOADING GUNS.

APPLICATION FILED JUNEZI. |917.

Patented Apr. 1, 1919.

4 SHEETS-SHEET 3.

A. T. DAWSON & G. T; BUCKHAM.

FIRING MECHANISM 0F BHEACH LOADING GUNS.

APPLICATION FILED 1UNE21. 1911.

Patented Apr. 1,1919.

4 SHEETS-SHEET 4.

UNiTED sTATEs PATENT oEEioE.

, ARTHUR TREVOB DAWSON AND GEORGE THOMAS BUCKHAM, 0F WESTMINSTEE,

LONDON, ENGLAND, ASSIGNOBS TO VICKERS LIMITED, F WESTMINSTEB,

LONDON, ENGLAND.

FIRING MECHA-N ISM HAM, both'subjects of the King of-Grreat l Britain, residing at-Vickers House, Broadv rel in single fire way, Westminster, in the county of London,

England, have invented certain new and useful Improvements in or Relating to the Firing Mechanism of Breech-Loading Guns, of which the following is a specification.

' This invention relates to firing mechanism in which there is interposed between the trigger or firing handle and the sear of the striker or firing needle, a spring controlled member which, when released bythe trigger, serves to transmit to the striker scar the necessary'movement for disengaging it from the striker.

According to the invention we provide in an automatic gun means whereby the aforesaid spring controlled member is 'automatically re-cocked during the recoil ofthe baroperation, the said means preferably comprising a cam carried by the operating crank of the breech mechanism or by any other suitable part contiguous to and Vmovin with the crank. The said spring contro led member may be in the form of a plunger with which engages a sear which is herein referred to as the secondary sear to distinguish it from the striker scar. This secondary sear is adapted to be displaced to release the spring controlled plunger by a sprin controlled slip pawl or tripping piece w ich isy suitably connected to the trigger or firing handle.

Means may be provided by the adjustment` of which the said slip pawl or tripping piece 'can at will be .caused-to perform its tripping function in relation to the second- @ary sear (thereby firing single shots) or can be prevented from performing this function in which'event the firing mechanism is set for the automatic operation of the gun. The said means may also be adjusted to a safe position in which condition the secondarysear is prevented from being disengaged from the spring plunger andthe gun cannot then be fired.

It may happen that during the firingwof the gun the lock does not quite reach lts forward orl firing position, the actuatingv 'handle on the crank shaft in consequence Specification of Letters Patent.

Fig. 1.

or BnEEcH-LOADINGGUNS.

being out of contact with its limit stop.

When this occurs it is customary to strike the actuat1ng handle smartly to brin it against its limit stop and move the loc to its forward position; it has been found that- .means may comprise a safety sear for enratend Apr'. '1, 1 919.

Application illed June 21, 1917. VSerial-N9. 176,110. I f Y gaging with a member moving with the v spring controlled plunger, this safet Sear being disengaged from thesaid mem er as the crank shaft completes its movement to bring the lock to its firing position.'

In order thatthe said mvention may be clearly understood and readily carried into 'effect we will describe the same more fully with reference .to the accompanying drawings, in which Figure 1 isa side elevation vshowing more or less diagrammatically a constructional form of the invention embodied in an automatic gun of the Maxim type, one side of the breech mechanism casing of the gun having been removed'to illustrate the invention moreclearly.

Fig. 2 is a plan of Fig.`1 with parts thereof in section on the lines 1, 1 and 2, 2 of Fig. 3 is a side elevation,fviewed` in the direction of the arrow in Fig. 2, of the change fire device.

- Fig. 4 is a side elevation of Fig. 3.

Fig. 5 and 6 are views similar to Figs. 1

and Q-but with the muzzle of the gunA directed toward the left---illustratii1g'v a constructional form of the means for preenlng the gun from being prematurely re Fig. 7 is a sectiontaken approximately on lthfet line 3, 3 of Fig. 5 and viewed' from the Fig. is a section taken approximately on theline 4, 4 of Fig. 5 and viewed from the `rlght.

A is the mechanismcasing of the automatic gun; A is the operating crank of the breech mechanism and A2 is the Crank shaft.V As represents the aforesaid cam moving with lthe crank A. 'B is the striker sear.v C

represents the spring controlled plunger and D represents the secondary sear appertaining to this plunger. E represents the spring controlled slip pawl or tripping piece for disengaging the said secondary sear from the plunger C. E2 (Figs. 5 to 7) represents the aforesaid safety scar for preventing premature firing of the gun.

In the example .shown the spring plunger C is connected by a pin c to a longitudinally displaceable rod C whoseforward end is pivoted to an arm C2* rigid with an arm C2 lying in Contact with the striker scar B. The rear end of this rod is connected to one arm o of a bell crank lever pivoted to the mechanism casing A, the other arm c2 being adapted to be operated upon by the aforesaid cam A3 on the crank A of the breech mechanism. The secondary seai- D is of bell crank formation; its horizontal arm has a nose-piece engaging with a recess or shoulder of the spring plunger C and its vertical arm is arrangede contiguous to the aforesaid spring controlled tripping piece E; the latter is pivoted to the rear end of a sliding rod E suitably connected to the trigger or firing handle which is not shown. When the trigger is arranged on the elevating or training handwheel or lever, the connecting vmeans comprise a bell crank lever e and a sliding pin e disposed co-axially with respect to the trunnions ex.

The plunger C, the secondary scar D and the tripping piece E are arranged within a casing F upon the outside of which is' pivoted a change over lever F provided Within the casing with a curved arm f pivoted at 7"c tothe casing F and provided with a stop f. This stop is adapted to occupy three different positions by moving the arm f about its pivot; in the first or safety position Which is that shown in Fig. 1 the stop cooperates with the vertical arm of the secondary scar D to prevent it from becoming disengaged from the langer C; in the second or automatic fire position, which is indicated by the numeral 1 in Fig. 1, the stop f is situated above the upper surface of a recess lin the tripping y iece E when the latter is displaced toward t ie left to lire the gun and this tripping piece is thereby prevented from performing its slip function; in the third or single fire position which is indicated by the numeral 2 in Fig. 1, the stop f is situated contiguous to an upward projection on the tripping piece so that when the latter is displaced to fire the gun it is moved by the stop into the position shown by chain linesin Fig. 1 and is therebys1ipped from the secondary Sear D.

When' the change over lever F and the stop f are in the single fire position, the plunger is 1'e-cocked by the aforesaid cam As on the operating crank A. When the said lever and stop are in the automatic lire position, the secondary Sear D is retained out of engagement with the plunger C as long as pressure is exerted upon 'the trigger or firing handle; in this condition of affairs the striker sear B is released automatically as the barrel approaches for reaches its forward position after recoil, by the cooperation of part of the barrel extension with the striker sear.

The initial manual cooking of the plunger C prior to automatic or single fire operation is effected by the usual hand lever (not shown) on the outer part of the crank shaft A2.

- When this hand lever is actuated the aforesaid cam A3 on the crank A depresses the bell crank lever c', c2 which is connected to the longitudinally displaceable rod C', and ompresses and recocks the spring plung The safety sea-r E2 (see Figs. 5 to 7) is pivoted at e2 to a fixed bracket E3 between which and the safety scar a spring e (Fig. 5) is interposed; this spring tends to hold the safety sear in engagement with an extension c* of the arm c so that a shoulder on the safety sear E2 (see Fig. 5) prevents the arm c and therefore the spring plunger'C from moving to liberate the striker sear B. The safety sear E2 has an arm E2X Which lies in the path'of a. projection A4 moving with the crank shaft A2. In the example shown this rojection is carried byl the aforesaid cam 8 and is sol arranged that as the crank shaft' completes its movement to bring the lock to its firing position, the projection will come against the arm E2x and disengage the safety sear E2 from the extension 0' of the arm a.

. What we claim and desire to secure by Letters Patent of the United States is l. An automatic gun having'iring mechanism comprising a spring controlled member which, when released, transmits movement to the striker sear for releasing the striker, and provided with means whereby the said member is automatically re-cocked during recoil of the barrel in single fire operation.

2. In an automatic un, the combination with the operating orari of the breech mechanism and firing mechanism comprising a spring controlled member which, when released, transmits movement to the striker sear for releasing the striker, of means movingvangularly with said crank for automatically re-cocking said member during recoil of the barrel .in single fire operation.

l3. In an automatic gun the combination with the operating cran of the breech mechanism and firing mechanism comprising a spring controlled member which, when released, transmits movement to the striker sear for releasi the striker, of a cam moving with the said operating crank in 'such I manner that when the said crank is displaced during hand operation and during recoil of the barrel in single fire -operation it cocks .the said spring controlled member.

4. In an automatic gun, the combination of a spring controlled member which when released transmits movement to the striker sear for releasing the striker, a scar engaging with the, said member, a slip pawl or tripping piece for displacing the latter sear to release the spring controlled member and means for at will causing the pawl or tripping piece to perform or preventing it from performing its tripping function, substantially as described.

5. An automatic gun provided with firing mechanism comprising a spring. controlled member which when released transmits to the striker sear the necessary movement for disengaging it from the striker, means for automatically re-coc-king the said member during the recoil of the barrel in single Y fire operation and means for preventing the said member from disengaging the striker 'sean until the lock approaches its ring position. v

6. An automatic gun provided with firing mechanism comprislng a spring controlled member which when released transmits to the striker Sear the necessary movement for disengaging it from the striker, means for automatically re-cocking the said member during the recoil of the barrel in single fire operation, a safety sear adapted to prevent firing movement of the said member and a projection moving with the crank shaft of the breech mechanism for displacing the safety scar to liberate the spring controlled member fas therlock approaches its firing position.

In testimony whereof We have hereunto affixed our signatures. c

ARTHUR TREVOR DAWSON. GEORGE THOMAS BUCKHAM.

Witnesses:

JNO. R. CAsWELL, -GERTRUDE WHYTE.