US2495428A - Semiautomatic pistol with blowback breechblock - Google Patents

Description

SEMIAUTOMATIC PISTOL WITH BLOWBACK BREECHBLOCK' Filed June 4, 1948 E. J. slMoNsoN ETAL Jan. 24, 195o 2 Sheets-Sheet'l 1 Jan. 24, 1950 E. J. slMoNsoN ETAL SEMIAUTOMATIC PISTOL WITH BLowBAcx BREEcHBLocx Z'Sheets-Sheet 2 Filed June 4, 1948 N QL Patented Jan. 24, 1950 SEMIAUTOMATIC PISTOL WITH BLOWBACK BREECHBLOCK Ernest J. Simonson and Joan Carter Simonson, Muskegon, Mich.

Application June 4, 1948, Serial No. 31,177

3 Claims. 1

This invention relates to ilrearms and more particularly to a semi-automatic pistol with a blow-back breech block.

A main object of the invention is to provide a novel and improved semi-automatic pistol which is simple in construction, inexpensive to manufacture and which is reliable in performance, said not require any milling operations, the barrel and rlng mechanism being secured in said main body in a simple manner and wherein wearable parts are very easy to replace whenever required.

f Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

Figure 1 is a vertical longitudinal cross-sectional view taken through a semi-automatic pistol constructed in accordance with the present invention.

Figure 2 is a horizontal cross-sectional view taken on line 2-2 of Figure 1.

Figure 3 is a cross-sectional view taken on line 3-3 of Figure 1.

Figure 4 is a cross-sectional View taken on line 4-4 of Figure 1.

Figure 5 is a side elevational view of the semiautomatic pistol of Figure 1.

Figure 6 is a fragmentary longitudinal vertical cross-sectional detail view taken through the upper rear portion of the pistol of Figure 1, showing a cartridge being loaded from the magazine into the ring chamber of the pistol responsive to the rearward movement of the breech block.

Figure 7 is an enlarged cross-sectional detail view taken on line 'I-'I of Figure 5.

Figure 8 is an enlarged cross-sectional detail viewA taken on line 8-8 of Figure 1.

Referring to the drawings, II designates the main body of the pistol, said main body being made, for example, as a die casting and being formed with a top frame portion I2 and with a grip portion I3. The body is further formed with the nger guard portion I4. The trigger of the pistol is designated at I5 and is pivoted within the top frame portion I2 at I6.

Top frame portion I2 is formed with a longitudinal bore which contains a Wear sleeve IT,- said sleeve being split longitudinally and engaging with a longitudinal internal rib I8 formed in said bore, whereby rotation of sleeve I1 in the bore is prevented. Slidably positioned in the sleeve I'I is a breech block I9, said block having a forwardly extending tubular portion 20. Secured within the forward end of tubular portion 20: as by welding or brazing, is a stop ring 2|. Secured to breech block I9 is a finger-engaging projection 22 extending laterally through a longitudinal slot 23 formed through the rear portions of sleeve I1 and top frame portion I2.

Threaded into the forward end portion of top frame portion I2 of the pistol body is a plug member 24 formed with an elongated rearwardly extendingbarrel 25 terminating in a ring chamber member 26. The member defined by elements 24, 25 and 26 is axially 'formed with-a rifled bore 21. .As shown in Figures 1, 2 and 6, the rear end of member 26, converges inwardly to- Ward the end of bore 21 and defines a conical recess 28 adapted to receive the rim of a cartridge 29, when said cartridge is in firing position in member 25, as illustrated in Figures 1 and 2. Encircling barrel 25 is a coiled spring 30 which bears between ring 2I and member 26 and biases the breech block I9 forwardly toward the position shown in Figures 1 and 2.

Slidably mounted in breech block I9 is the firing pin 3I, said pin being provided with a rear head portion 32. Head portion 32 is located in a bore containing a spring 33 encircling pin 3l and biasing head portion 32 rearwardly toward a position wherein it projects slightly from the rear end of block I9. In this position the pin 3I engages the rim of the cartridge 29 in chamber 26 and when the head portion 32 is struck, as will be subsequently described, the pin 3l iires the cartridge.

The grip portion I3 is formed with a cavity 34 in the upper portion of which is pivotally mounted, by a transverse pin 35, the hammer 36, said hammer being shaped generally as the sector of a circular disc. Sleeve I1 is longitudinally slotted at 37 to allow hammer 36 to rotate upwardly into striking contact with the end of head portion 32, as shown in dotted view in Figure 1. Pivotally engaging the hammer 36 rearwardly adjacent pin 35 is the top loop 38 of a twisted wire rod member 39 whose bottom end is received in a recess 40 formed in the bottom of cavity 34. Designated at 4I is a Sear bar formed with a sharp bottom bend 42 pivotally engaging in a V- shaped recess 43 formed forwardly adjacent recess 46 in the bottom of cavity 34. Bend 42 terminates in an apertured arm 44 through which the twisted wire rod 39 slidably passes. Encir- 34 with another cavity 46 which receives the i cartridge magazine 41. Magazine 41 is conventional in structure and is releasably held in cavity 46 by a spring-biased detent lever .48 pivotally carried by grip portion I3 at its bottom end fand engaging a notch in the rear wall A of the .magazine to lock the magazine in place. The detent lever 48 may be manually rotated counterclockwise from the position shownin Figure 1^to `release the magazine. The magazine contains a follower spring 49 acting upwardly on a follower .block 5I).

The cartridges are stacked above the `block 55 and are lurged upwardly .by the .action of spring 43. The top end .of .magazine 41 is open and is formed with upwardly-.inclined .inwardly-convergent anges 5I,.5| which-guide .the cartridges toward the firing chamber as -Said cartridges 4are moved upwardly. The 4.tubular breech block extension 20 is suitably apertured at -52 forwardlyof the block I9 to provide-apassage for the upward movement vof Athe cartridges f into the firing chamber when the .breech .block is in a rearwardly moved position, as shown in .'Figure 6.

Hammer 36 is formed with anarcuatepassage A53, eccentric withrespect to-,pin 35, which1extends from its bottom edge to its top edge, land'extending through said passage and longitudinally movable-therein is a .curved vertical depending hook element 54 formed at the rear end of :a -sear rod 55. Sear rod 55 is-formed of stii wire aand extends horizontally aroundzthe top.end 1of=maga zine 41, passes transversely through the .upper forward portion of trigger I 5, .as shown at .56, `and is secured at -its forward end :to the .upper y portion of a coiled spring 51 seated Ain a recess 58 formed in body H, at .the trigger guard fporvtion I4. The transverse searrod'portion'561makes a vpivotal connection with the'upper forward por tion of trigger I5, and when the `ltrigger -I 5 fis pulled rearwardly, the Sear rod 55 is moved`=longi tudinally forwardly, compressing spring 51, the end of hook element 54 moving the sear bar 41'I :forwardly out of engagement with the notch in hammer 35. This releases the hammer, whereby the spring `is allowed to expand and rotate the centric passage 53 and the end of the hook ele-r ment v54 slips into the opening 54', releasing the vpressure of said hook element on the sear'bar 4I..

The sear bar 4| is then returned by spring 45 :into contact with the smaller end of hammer '36.

' Rearwardly of the ring chamber portion '26, s'leeve I1 is vformed opposite slot 23 with an fin- -wardly struck lug 59, breech block I9 being formed with a'longitudinal groove 6I] slidably Areceiving said lug 59, whereby the breech block' is longitudinally slidable inthe sleeve I 1 and vis held against axial Arotation therein. Lug 591s iorme with an inclined inner edge 6I which is engaged by a rearwardly moving cartridge shell after explosion thereof and causes said shell to be ejected laterally through the slot 23, as will be presently explained.

Secured to the rear end wall of the bore cavity dened by sleeve I1 is a cushion member G2 of `suitable resilient material, such as rubber or the '.like, which cushions the rearward impact of the breech block I9 on recoil.

To cock the pistol, breech block I9 is manually retracted by means of projection 22. As said lbreech block uncovers the opening 52 communi- -cating with magazine 41, the uppermost car- `tridge 29 :therein is moved upwardly into the inclined position shown in Figure 6, the nose of the cartridge entering the conical recess 28 and being moved into the end of bore 21. When the breech block is released, it pushes the cartridge into the ring chamber portion 2'6 and the parts .assume .thepositions .shown inligure l. -It will benoted .that rearward movement of .the breech -block rotates lthe 'hammer .36 .downwardly .and .allows .the .top end .of .sear .har 4I to interlock withthemotchin theforwardend of the hammer,

so that 4when the vbreech block is released, the -hammer is held by thesear bar inthe cockedpo- .sition .of Eigure .1.

lWhen the trigger 'is pulled, the .end of hook .portion .54 moves .the searlbar 4I forwardly out .of engagement with=the Vhammer notch,.as above explained, .and .said .end .enters opening 5I' .as the .hammer .is rotated .upwardly by spring 45 to .strike :the lring .pin head .32 .and re the car r tridge. `'.'llhe lead .pellet .is .blown -forwardly through `the .bore -21. The recoil of the .exploding gases moves the cartridge shell and breech block I9 rearwardly. The `shell engages `the inclined .lug zedge Il and is ejected .laterally through the slot 23.

The rearward movementof breech block 19 o n recoilrotates-hammerrdownwardly and the top .end Kof .sear -barv 4I lagain interlocks with 4the notch .in :the 'forward `end `of said hammer. At the same time a new cartridge is moved upwardly by the action of the spring-biased follower block 50, and enters the space between breech -block I9 .and .firing chamber l2E in the position of Figure 6. Spring 30 is compressed vby the rear- 'ward recoil -movement of the breech block, and after the recoil force is spent said spring returns the .breech block to the position shownin Figure l. Upon release of trigger ;I5.spring 51 moves 'element-54 'rearwardly out of opening 54', whereupon the -piston may again be med, to repeat .the above described action. VIt is thus seen that 4after .the pistol has been linitially cocked manual- .ly .it -is vmerelynecessary to pull the trigger each time it is desired to -re a-cartridge and to then `'release the trigger. The pistol is Vautomatically recocked by the -recoil of the fired cartridge.

The parts carried in top frame lportion I 2 may be readily removed vfor cleaning by unthreading .the .plug .member 24 from the forward Vend of `said :top frame portion. 'To facilitate this operation, the forward end of `said plug member `is formed with aligned radial notches '63, B3 into which the :edge of a. .coin orthe :blade of a screw V.driver may be inserted for .rotating said plug member with respect to the mentioned `top .frame portion I 2.

Secured .to the -sides of the grip portion 4I3 are cover .plates .64, 64 .of suitable knurled =or other` 15 the like. from Figure .3 it will be :seen .that

access to the interior of grip portion I3 may be.

had by removing the cover plate 64'.

While a specific embodiment of an automatic pistol has been disclosed in the foregoing description, it will be understood that various modications within the spirit of the invention may occur to those skilled in the art. Therefore it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.

What is claimed is:

1. In a semi-automatic pistol comprising a pistol body having a hollow grip portion, a slidable breech block with a firing pin extending movably therethrough, and a trigger pivoted at one portion thereof in the pistol body, the combination of a hammer extending rearwardly in cocked position andv pivoted at the forward end thereof in said pistol body below the level of the breech block and having a notch in the forward end thereof, the hammer being rotatable upwardly into striking contact with the rear end of said pin, a sear bar pivotally mounted in the grip portion and extending upward forwardly adjacent the hammer, resilient means biasing the upper end of the sear bar rearwardly into engagement with the notch on the hammer to cock the latter and simultaneously acting on said hammer to bias the hammer upwardly, a rod member in the pistol body pivotally connected to the trigger eccentrically of the pivot mounting thereof and having a rear depending hook portion extending about but out of ,contact with the pivot mounting of the hammer and movable forwardly into engagement with said sear bar in response to operative rotation of said trigger and thereby effective to release the sear bar from the notch on said hammer and allow the latter to rotate upwardly and strike the firing pin under the bias of said resilient means, the hammer being engageable by said breech block as the latter is moved rearwardly to rotate said hammer downwardly to the cocked position wherein the upper end of said sear bar engages in the notch of said hammer, and further resilient means biasing the rod member rearwardly with its rear depending hook out of operative engagement with said sear bar.

2. In a semi-automatic pistol comprising a pistol body having a hollow grip portion, a slidable breech block with a firing pin extending movably therethrough, and a trigger pivoted at one portion thereof in the pistol body, the combination of a hammer extending rearwardly in cocked position and pivoted at the forward end thereof in said pistol body below the level of the breech block and having a notch in the forward end thereof, the hammer being rotatable upwardly into striking contact with the rear end of said pin, a sear bar pivotally mounted in the grip portion and extending upward forwardly adjacent the hammer, an apertured rearwardly-extending projection upon the lower end of the sear bar, an elongated spring guide member extending upwardly through the aperture in the latter projection and pivotally connected at the upper end thereof to the hammer eccentrically of the pivot mounting thereof, a stop on the spring guide l member spaced a distance below the hammer, a

helical compression spring mounted on said spring guide member in a position to engage downwardly upon said rearwardly-extending projection of the sear bar and the stop on said spring guide in order to bias the upper end of said sear bar rearwardly into engagement with the notch on said hammer and to bias the latter upwardly, a

frod member in the pistol body pivotally con- -bar from the notch on said hammer and allow the latter to rotate upwardly and strike the nring pin under the bias of said helical spring, the hammer being engageable by said breech block as the latter is moved rearwardly to rotate said hammer downwardly to the cocked Position wherein the upper end of said sear bar engages in the notch of said hammer, a second spring engaging with the rod member forwardly of the trigger and biasing said rod member rearwardly with its rear depending hook out of operative engagement with said sear bar.

3. In a semi-automatic pistol comprising a pistol body having a hollow gri-p portion, and a slidable breech block with a ring pin extending movably therethrough, the combination of a trigger pivoted at one portion thereof in the pistol body forwardly of the normal operative position of said breech block, a rearwardly-flaring hammer extending rearwardly in cocked position and pivoted at the forward end thereof in said pistol body below the level of the breech block and having a notch in the forward end thereof, the hammer being rotatable upwardly into striking contact with the rear end of said firing pin, a sear bar pivotally mounted at the lower end thereof in the grip portion and extending upwardly forwardly adjacent the hammer, a rearwardly-extending apertured projection upon the lower end of the sear bar, an elongated spring guide member extending upwardly through the aperture in the latter projection and pivotally connected to the hammer eccentrically of the pivot mounting thereof. a stop on the spring guide member spaced a distance below the hammer, a helical compression spring mounted on said spring guide member in a position to engage downwardly upon said rearwardlyextending projection of the sear bar and against the stop on said spring guide in order to bias the upper end of said sear bar rearwardly into engagement with the notch on said hammer and to bias the latter upwardly, a rod member in the pistol body pivotally connected to the trigger eccentrically of the pivot mounting thereof and having a rear depending hook portion extending through the hammer and movable forwardly into engagement with said sear bar in response to operative rotation of said trigger and thereby effective to release the sear bar from the notch on said hammer and allow the latter to rotate upwardly and strike the firing pin under the bias of said helical spring, the hammer being engageable .by said breech -block as the latter is moved -rearwardly to rotate said hammer downwardly to the cocked position wherein the upper end of said sear bar engages in the notch of said hammer, a forward projection upon said rod member extending forwardly of said trigger, a spring in said pistol body engaging against said forward projection and biasing the rod member rearwardly with its rear depending hook out of operative engagement with said sear bar, said sear bar having a transverse aperture therethrough above the normal p0- sition of the lower termination of the rear depending hook portion on the rod member, and an eccentric cam portion -u-pon the hammer effective to raise said rear depending hOOk portion upon 'from effective contact withssaid hook :portion and allow the' same under the bias of the .rst-mentioned helical spring -to engage resilientlyagainst the forward end of the hammer and upon downward movement thereof .by means of the breech :block to engage with the notch on said hammer,

and thereby cock the latter for a new cycle of operation.

ERNEST .J. SIMONSON.

J GAN CARTER :SIMONSON REFERENCES .CITED UNITED STATES PATENTS Number 'Name Date 1,017,119 Ioborgv Feb. 13, 1912 1,138,379 Hammond May 4, 1915 1,405,765 Diehm Feb. 7, 1922 FOREIGN PATENTS Number Country Date 226,588 Germany Oct. 6, 1910 464,054 France Jan. 5, 1914

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