US1427079A - Crank-operating gear for moving the breech in machine guns - Google Patents

Description

A. H. G. FOKKER. CRANK OPERATINGGEAR FOR MOVING THE BREECH IN MACHINE GUNS.

APPLICATION FILED SEPT. 1. I920- v 1 427 079 Patented Aug. 22, 1922 wlfiZ/w UNITED STATES PATENT OFFICE.

ANTHONY HERMAN GERARD FOKKEIR, OF AMSTERDAM, NETHERLANDS.

CRANK-OPERATING GEARFOR MOVING THE BREEGH IN MACHINE GUNS.

Application filed September 1, 1920. Serial No. 407,539.

To all whom itmag concern.-

Be it known that I, ANTHONY HERMAN GERARD FOKKER, a subject of the Queen of the Netherlands, residing at Amsterdam, Netherlands, have invented certain new and useful Im rovements in Crank-O erating Gear for Kloving the Breech in achine Guns (for which I have filed a plication in Germany, No. 310,067, filed Fe 12, 1918), of which the following is a specification.

The type of machine gun in which the breech block, the movement of which places a cartridge in position and operates the firing pin, is given a reciprocating movement by mechanical means, such as a rotating crank, instead of being returned to the cooked position by the recoil of the explosion in the gun, is well known. In the usual form of construction in such a gun, the extreme forward position of the crank brings the breech block to the point where it holds the cartridge in position and the shot is fired.

The object of the present invention is to provide a means of bringing the breech block into its forward position before the operating crank has reached the end of its throw in order to utilize the remainder of that throw for operating a device for locking the breech block in position before the shot is fired. This means of locking forms the subject of my copending apglication for Letters Patent of the United tates, Serial No. 407,540, filed September 1, 1920.

The accompanying drawing illustrates the construction of the n mechanism which forms the subject of this invention.

In said drawing Figs. 1 and 2 respectively show vertical and horizontal sections through the gun mechanism.

Fig. 3 is a cross section through A-B Fig. 1.

The operatin crank A is connected to the breech block E by means of a connecting rod, which. however, consists of two telescoping parts and C, one of which slides axially inside the other, the two parts being extended as far as allowed by the crank A and the breech block E by means of a spring D.

When the crank A has completed part of its forward throw as indicated by the center line F, the breech block is forced against the abutment G and holds the cartridge carrier- L in place. In continuing its rotation from the position shown from the center line F to its furthest forward point (the position in WhlCh 1t 1s shown in the diagram), the crank A forces the two parts of the connecting rod together, thus compressing the spring During this time the breech block E remains stationary while the movement of the crank is utilized to move the lockin levers K into the position in which they look the breech block in the manner described in my copend ng appl cation hereinbefore identlfied, Serial No. 407,540. When this has been efi'ected the shot is fired. The continued rotation of the crank A first unlocks the breech block by moving the locking levers K, duringwhich time the breech block remains statlonary while the two parts of the connectmgrod slide outwards, decompressng the spring D. When the connecting rod 1s fully extended the further rotation of the crank draws the breech block away from the abutment and the cycle of operations is repeated by the means described. The rotation of the operating crank remains continuous and uniform throughout the cycle of operations.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 2-- 1. In a breech block mechanism for machine guns, a rotating crank, a connectin rod between the crank and the breech block,

divided into two parts in a manner allowing the said connecting rod to change in length during the transmission of the movement of the crank to the breech block, whereby the movement of the breech block is less than the total throw of the crank.

2. In a breech block mechanism for machine guns, a rotating crank, a connectin rod connecting the operating crank with the breech block, divided into two parts, one sliding axially within the other, and a spring holding the two parts extended as far as allowed by the relative positions of the crank and the breech block.

In testimony whereof I afiix my signature in presence of two witnesses.

ANTHONY HERMAN GERARD FOKKER. Witnesses:

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