US1382317A - Automatic pistol - Google Patents

Description

' Patented June 21 ammo/Mom mum/7,

UNITED STATES aarss'r ,QFFHCE.

EDWARD s. POMEROY, or SPRINGFIELD, MASSACHUSETTS, ASSIGNOR To SMI H & WESSON, or SPRINGFIELD, MASSACHUSETTS, A VOLUNTARY TRUST AssooIATIoN. v

AUTOMATIC PISTOL.

To all whom it may concern:

Be it known that I, EDWARD S. PoMERoY, a citizen of the United States of America, residing in Springfield, in the county of Hampden and State of Massachusetts, have invented certain new and useful Improvements in Automatic Pistols, of which the following is a specification.

This invention introduces certain improvements in automatic pistols, particularly those of the gas-operated or blow-back type, wherein the hammer is cocked, the spent shell ejected, and the barrel reloaded by the movement of a breech block WlllCll is thrown backby the reaction of the gases when the pistol is fired.

The improvements relate to the operative connection between'the hammer and sear, and the means for pressing the sear into position to hold the hammer cocked; and to a detachable stop for limiting the forward movement of the .housing slide normally connected to the breech block.

An embodiment of the invention is illustrated in the accompanying drawings, wherein I Figure 1 is a side elevation, partlyin vertical section, showing the pistol cocked and ready for firing, except that the trigger is blocked by the automatic safety device;

Fig. 2 is a.-. fragmentary vertical section showing the hammer thrown forward in the position it occupiesat the instant of firmg, the trigger being still held pulled;

Fig. 3 is asimilar section showing the operation of cooking, the breech block and housing having been thrown back by the recoil;

Figs. 4 and 5 show the hammer andsear detached in two .difl'erent positions, the hammer being partly in section F 1g. 6 is a rear view ofthe parts in the position shown in Fig.

Referring to ,the drawings, the. plstol shown is of the well known Smith & Wesson type. The barrel A is mounted in the usual manner upon the main frame B,.which. in-

cludes the hollow stock or grip C within which is insertedthe magazine (not shown) in the usual mannen Behindthe barrel; is the breech block D, which is mounted to slide in the usual. breech openingE, andis normally lockedby a catch Fto a sliding housingor'hoodG which overlies the barrel and stock, and is thrown back withfthe Specification of Letters Patent. Patented une 21, Application filed January 8, 1921. Serial No. 435,820.

breech block by the back pressure of gases in fir1ng, so that it occupies momentarily the posltion shown in Fig. 3, being instantly thereafter projected forward bythe stress of its actuating spring H,-which isjconfined wlthin a chamber in the housing in the Well understood manner, pressing forward against the housing and backwardly against the solid rear wall of this chamber.

. through the link is so nearly alined with the pivot of the hammer that the spring acts at itsminimum mechanical advantage; while as the hammer falls, the spring-. stress'is communicated with continually increasing advantage until the position shownin Fig.

2 is reached. ,The hammeris held cocked by a sear K pivoted to the hammerat 13, extending thence downwardly, and having a shoulder 14 which seats upon a ledge 15 which be conveniently fQI II1eCl1 aS part of the rear wall '16 of the magazine chamher, this wall being cut away above 15 to form a recess inwhichthe seanmay play. The-sear carries a transversely-movable catch-piece 17 the construction of which is fully set-forth in patentto J.',H. Wes-;, son, No. 985,482. Against ,this catch-piece .acts the rear face of a trippingjmember18 forming part ofzthe trigger L, or

suitably connected thereto, so that when the trigger is pulled the sear is pushed rearwardly off from the ledge15, leaving the hammer unsupported, and as the hammer falls, the sear: is pushed endwise down into a chamber 20 behind thewall l6, as shown in Fig. 2. The fall of the hammer acts throughthe usual firing pin to explode the cartrid e and the ex )losion isfollowed b the usual recoil movement, at the end of' which the parts are n the position shown in Fig. 3, the breech block having moved,

over the hammer and thrown the latter back i to its extreme position. In this movement the-sear is liftedand (the trigger being'still held, as the time is too short to have per-V mitted its release) the catch-piece 17 passes up alongside the tripping member 18 of the trigger, being pressed in in this movement, but springing out upon the release of the trigger to again get behind the tripping member 18, being the position shown in Fig. 1.

The arm is provided with the usual automatic safety device consisting of a fingerpiece M acting through a bar 21 pressed forward by a spring 22 against an upright locking slide 23 carrying at its upper enda locking block 24 which lies behind the tail of the sear and prevents the latter being pushed back until this block is displaced by the backward movement of the bar 21, the connection between the two consisting of a pin 25 on the one part, and an inclined slot 26 in the other, the arrangement shown being such that the pulling back of the finger-piece M pushes up the safety bar 20 and elevates the block 24 to a point above the locking projection on the back of the sear, so that the latter may be freely pressed back by the trigger.

In this type of automatic arm as heretofore made, the sear has been acted upon by a long leaf spring mounted in the grip, work ing in the chamber 20, and bearing at its upper end against the tail of the sear, as shown in said patent No. 985,482.

The present invention substitutes a sear spring which is housed in the hammer. The construction is best shown in Fig. 4, where the hammer is bored out to form a chamber 30 in which is a helical spring 31 pressing outwardly against a plunger 32, having preferably an enlarged head 33, which bears against a face 34 on the rear of the sear, in the position shown in Figsrl, 3 and 4. 1n the position shown in Figs. 2 and 5, the

parts are so far separated that the plunger no longer bears against the sear, being held by a pin 35 from being pressed too far out by the sprin This pin 35 may be the same pin which orms the pivot 12 of the link 11, or it may be a separate pin. The hammer is formed with a face 36 which, when fully pressed back, as shown in Fig. 3, bears againstthe face 34 on the sear, thereby for the-moment rigidly connecting the two parts and communicating the cocking thrust of the breech block to the sear to force the latter positively into the position shown in Fig. 3, where'its shoulder 14 stands directly above the ledge 15, and the sear tail 37 strikes the back of the wall 16. This construction insures that the sear shall be brought positively into position for engagement with the ledge 15. Then upon the forward movement of the breech block, whereby the hammer is released and permitted to 'make a'slight initial upward movement, the sear is carried down and its shoulder 14 seated on the ledge 15, this movement of the sear being almost exactly longitudinal, any recoil or displacesear. In this position the clearance between 34 and 36 is suflicient to enable the sear to be pushed back by the trigger off from the ledge 15, and this backward thrust is opposed only by the comparatively light spring 31, and by the friction between the shoulder 14 and ledge 15, which friction is induced by the stress of the spring 9 acting, however, at a mechanical disadvantage, as above explained, by reason of the direction of thrust through the link 11. It results that a very light trigger pull will be sufficient to fire the arm.

Thus the described construction insures the bringing of the sear to cocking position by an absolute thrust, any recoil is prevented by the action of the sear spring carried by the hammer, while yet the sear in cocked position is free from any serious spring stress, and consequently the arm may be given a hair trigger fire.

In Wesson Patent No. 1,181,416, the forward movement of the slide or housing is limited by a transverse pin (therein lettered t) which, at the end of the forward movement under the stress of the actuating spring, strikes against a shoulder formed on an upright projection or post at the rear of the frame. In that construction, in order to dismount the housing the pin 25 may be driven out laterally, whereupon the housing, being disconnected from the breech block,

may be slid forward over the barrel and respring 42 within this socket, and its'upper end projecting into a cavity 43 where in'the normal forward position of the housing slide it is struck by a shoulder 44 thereon. The upward movement of the pin or bolt 1? is limited by a stop pin 45. When it is desired to dismountthe housing, any "pointed instrument, such as that shown at Q in, Fig. 1, may be inserted through a hole 46 in the top of the housing just over the pinP, and the latter thereby pressed down to beneath the top 'of the post 41, whereby the shoulder 44 is released and the housing may be'pressed forward by its spring HQ and dismounted. The cavity '43 is sufiiciently long so that in the extreme back-throw of the housing it 7 previously used, that there is no loose looking part which may become lost; that a larger locking pin may be used, and that the disconnection is more conveniently accomplished than by driving out a tightly fitted transverse pin.

While the invention is shown as applied to an automatic arm of the Smith & Wesson type, it is to be understood that it is not necessarily limited thereto, but may be applicable with other constructions, and that the preferred construction shown may be varied or departed from within the scope of the appended claims.

What I claim is 1. In an automatic pistol having in combination a movable breech block, a pivoted hammer arranged to be cocked by the breech block on its backward movement, a sear pivoted to the hammer and having a stop shoulder to rest on a fixed ledge in the frame, and a trigger adapted when pulled to engage said sear and push it off such ledge, the relative construction of hammer and sear with closely abutting shoulders adapted during the cocking movement to force the sear forward into position over such ledge, and a spring engaging the hammer and sear acting to press forwardly against the sear and prevent rebound thereof at the beginning of the return movement of the hammer and until the sear is seated on said ledge to hold the hammer cocked.

2. In a pistol according to claim 1, the sear spring engagingthe hammer and sear only, and acting to press them apart.

3. In a pistol according to claim 1, the sear spring carried by and reacting against the hammer.

4. In a pistol according to claiml, the sear spring carried by the hammer and movable to take up lost motion between hammer and sear between the extreme back-throw of the hammer and the cooking position of said parts.

5. In a pistol according to claim 1, the V V hammer having a socket, a spring in said socket, and a plunger in said socket seated against said spring and protruding therefrom to engage the sear. i

6. In a pistol according to claim 1, the hammer having a socket, a spring in said socket, a plunger in said socket seated against said spring and protruding therefrom to engage the scar, and a stop for limiting the protrusion of said plunger.

7. In an automatic pistol having a movable breech block and a housing slide normally connected thereto, a'stop forlimiting the forward movement of said housing slide, comprising a spring-pressed pin engagin said slide.

8. n a pistol according to claim 7, the

'60 housing slide having a hole through which an instrument may be inserted to depress 7 said spring-pressed pin to release the slide. In witness whereof, I have hereunto signed my name.

I EDWARD S. POMEROY.

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