US1895719A

US1895719A - Automatic firearm

Info

Publication number: US1895719A
Application number: US504924A
Authority: US
Inventors: Lahti Aimo Johannes
Original assignee: Individual
Current assignee: Individual
Priority date: 1930-07-05
Filing date: 1930-12-26
Publication date: 1933-01-31
Anticipated expiration: 1950-01-31
Also published as: FR714584A; BE377621A; GB379713A; CH156784A

Description

Jan. 31, 1933. A. J. LAI-ITI 1,895,719

AUTOMATIC FIREARM Filed Deo. 2s, 1930 Patented am. l

Lann, or' mesme, li'INLU-"IDl AUTOMATIC FIBEAREI ,.appuutn mea December 2e, leso, serial No. 504.924, and'in Finland my @5, man.

iii-invention 4relates to an automatic pistol in which the reaction ofthe gunpowder as .pressure and a spring force counter-actnig the as pressure act automatically at the 3 iiilngo the pistohthus effecting feeding 1n o'fa new cartridge, cocking of the pistol, firing off, and ejection of the empty cartridge.

''llhe accompanying drawing illustrates s .cliematically'one way ofcarrying out the invention in practice, and in it:

- Fig. 1 illustrates a vertical longltudinal s 'ectionfofthe automatic pistol accordlng to theinvention. Fig.f2 illustrates the automatic pistol in f side-elevation.

' Fig. illustr'ates the cocking parts ofthe automatic -pistol in horizontal longitudinal section.

. To'the butt-end of the pistol 1s attached "im the'A stationary barrel 31 of the pistol and around'it the cooling mantle 28 of the barrel. The cartridge case 1, which is either a prismatic tube or a round container, 1s 1.,. pishedfinto the feeding aperture in the butt- *5 end 40,th'e cartridge case 1 being retained in the feeding aperture by means of a notch in the side ofthe case'and a corresponding latch 3 pivoted in the butt-end and acted by afspring. A fceding spring in the cartridge case' '1 effects the feeding in of the cartridge inthe usualfmanner. The locking plunger 4' Q'f the cock'acts likewise as the hammer, the said locking plunger 4 having at the rear enditheshape of'a`piston 41, which moves in 'W5 the "stationary cock cylinder 25 in the butthelical spring guidedby a pin 42v acts Ibetween the hefad 32 of the cock cylinder mantle 3 3' andthe locking plunger 4. The' resetting sV ring 8 extends into a centric 'UO bor'43fiix'the ocking' lunger 4, thus making the cock shorter. t the commencement of theirin'g the cocking bolt 5, fitted into the butt-end 4,V is pulled backwards. At the fore ed of the cockingbolt 5 there is a latch 44 prtrilding through a longitudinal cut in tliecock cylinder mantle 33 behind the pistbn 4I the locking plunger 4. The lock- 4`tliu's :moves against the action M o f'til'resettin 's'pringB compressing same. 39" The "stop 6 o the trigger mechanism is pressed behind the shoulder 46 of the locking plunger 4 thus retaining the plunger. The locking piston 41 has'expelled the air from the cock cylinder 25 through holes 22 in the cylinder head 32. These holes 22 are 55 furnished with ya check valve made up of a disc 26 in the valve body 47, the said disc 26 being pressed against the holes 22 by a spring 27. The air escapes through an aperture 24 from the valve body 47. The pistol now beingcocked the cocking bolt 5 is released and reassumes by action of the cocking bolt spring 7 its original forward position and is retained there duringthe firing. When the trigger 15 is pulled the stop 6 1s forced downwards, the locking plunger 4 is released and moves forward by action of the resetting spring 8. 'Due to the

check valve

26, 27 now closing the air passages 22 a vacuum is created in the cock cylinder 25, retarding the forward motion of the locking plunger 4. T'he mantle piece 33 of the locking cylinder 25 may be furnished with a small hole, through which air is let into the cylinder. The e'ect of the vacuum brake 75 may be varied by means of adjusting the size of the hole. The forward end 16 of the locking plunger 4 pushes the cartridge from the mouth of the cartridge case 1 into the cartridge chamber 17 andnally the firing 80 needle 18 at the foremost end of the locking plunger 4 strikes the percussion cap of-the cartridge, thus effecting the firing off of the cartridge. The empty cartridge and the locking plunger 4 are forced backwards by reaction of the gunpowder gases. The eX- tractor 19 pulls the cartridge until the ejector notch 20 in the opposite side ejects the cartridge through the discarding aperture 21. In the foremost part of the lock and above the mouth of the cartridge magazine the cartridge channel 50 is located. In this channel 'the cartridges and the front end of the bolt 4 move successively. The guiding of the empty cartridge in the said'channel 50 is se- E cured by the wall of the channel being provided with a special guiding bar 51 the inner edge of which is parallel or only slightly oblique to the longitudinal axis of the channel and located from the said axis substantialy the same distance as the maximum ra- `dius of the cartridgechamber 17. By this provision the empty cartridge can not, even 1n case the butt edge of the cartridge or the 5 extractor 19 notch are worn, turn crosswise in the channel even .to such a slight extent that the extractor 19 would loose its grip on the cartridge thus resulting in 'improper oeration of the automatic feature. The gui l0 ing is rendered most ei'ective by locating the guiding bar 51 diametrically o posite to the extractor 19. The cartridge .is y this means trapped 'between the guiding bar 51 and the extractor 19 thus retaming its positive axial position. By means of the above described mechanism the empty cartridge is removed in its proper position to the ejector notch 20 which throws the cartridge out through the discarding aperture 21. 80 Whatis claimed is: Y

1. An automatic firearm operating by l means of reaction pressure comprisingJ a cartridge chamber a cartridge channel 'sosed adjacent said chamber, said channel ing pro'vided with a lon 'tudinal guiding bar, the inner e e of whic I is substantially parallel to the axis of said channel, said inner edge also being disposed at substantially the same distance from the axis of said channel as the radius ofl said cartridge chamber.

/ 2. An automatic firearm operating by means of the reaction pressure comprism a cartridge chamber, a cartridge channel 1sposed adjacent sald chamber, an extractor positioned in said channel a lon 'tudinal llxiding bar also positioned in sai channel 'ametrically opposite to said extractor, the

inner edge of said guiding bar extending substantially parallel to the -axis of said chan- '40 nel and the 1nner edge of said bar also being disposed at substantially the same distance from the longitudinal axis of said channelv as the radius of said cartrichamber.

In testimony whereof I A my signature. AIMO JOHANNES LAI-ITI.