US2396564A - Firearm - Google Patents

Description

March 12; 1946. A. GAL 2,396,564

FIREARM Filed Jan. 30, 1939 Fig. 1

INVENTOR ALLESANDRO GA'L 6v 4 6 ATTYS.

Patented Mar. 12, 1946 FIREARM Alessandro Gal, Oltrona a1 Lago, Gavirate, Varese, Italy; vested in the Alien Property Custodian Application January 30, 1939, Serial No. 253,661

In Italy February 5, 1938 2 Claims.

This invention relates to breech closing means for firearms and more particularly for automatic and semi-automatic firearms and it comprises a breech closing mechanism in which the breech bolt cooperates with a slider mounted to move longitudinally with respect thereto, said slider cooperating with means to lock said breech bolt in breech closing position.

An entirely reliable and self-locking closing mechanism is obtained in accordance with this invention by means of parts to which a translatory rectilinear movement only is imparted and with the aid of fiat sloping surfaces which may be easily machined with full precision as required.

An embodiment of this invention is illustrated by way of example on the annexed drawing and Figure 1 is a longitudinal fragmentary section on the barrel axis of an arm equipped with the means of this invention the breech bolt being in closed position.

Fig. 2 is a longitudinal section similar to Fig. 1 with the breech bolt in open position;

Fig. 3 is a longitudinal section, on an enlarged scale, through the firearm of Fig. 1 taken along the line 3-3 thereof;

Fig. 4 is a cross-section, also on an enlarged scale, through the firearm of Fig. 1 taken along the line 4-4 thereof and looking in the direction of the'arrows;

Fig. 5 is a side view of a separate locking member and Fig. 6 is a top plan view of the locking member shown in Fig. 5.

Fig. 7 is a perspective view of the locking member oi'Fig. 5.

In Figures 1 and2, l denotes the firearm barrel and 2 denotes the receiver which has grooves 8 in internal faces of opposite walls thereof, said grooves being connected with sloping seats I0 which diverge transversely to the respective grooves 8 connected therewith and are inclined to the direction in which said groove extends.

An elongated member 26 which serves as a breech bolt is mounted to reciprocate in the chamber confined within the receiver 2 and said enters; said spring abuts on a plug 34 closingthe receiver 2 at its rear end.

The bolt 26 has a transverse slot 35 bounded by side portions 26' intermediate its extension 30 and its spring socket 3| and a slider 32 is mounted to reciprocate along said bolt 26 within the slot 35 thereof.

The slider 32 has upper and lower extensions 33 adapted to embrace the bolt central extension 30 and to abut on the transverse faces 29 of the bolt 26.

Looking shoes 9 are provided for cooperation with the bolt 26, the slider 32 and the receiver 2, and each of said shoes includes a main body (Figs. 5, 6 and 7) having transverse faces 36, 31 at its longitudinal ends and a uiding lug II adapted to enter a cooperating receiver groove 8. On each side the locking shoe 9 provides a nose confined by longitudinally extending faces I2, I 2 and by sloping end faces I3, I3, the faces l2, I2 being intended to slide along cooperating surfaces of the receiver 2 and slider 32 while the sloping faces I3, I3 have an inclination registering with that of the side surfaces of the sloping seats Ill.

The sloping seats H], as shown in Figs. 2 and 3 extend downwardly beyond the inner levels of the grooves 8, so that when the shoes 9 arrive in locking position adjacent the openings of the sloping seats III, the inclined faces I3, I3 engage the said seats at said openings and the shoes 9 move outwardly into the chambers or spaces provided between the slider 32 and the bolt lugs 28, and thus into the locking position shown in Fig. 1, in which the faces I2, I2 of the shoes lie in the seats I0.

The respective positions of the bolt 26, slider 32 and locking shoes 9are shown in Figures 1 and 2. When the bolt 26 is in its open position (Fig, 2) said locking shoes 9 are positioned in the space intermediate the transverse faces 29 of the bolt 26 and the opposite end faces of the extensions 33 of the slider 32 which are in their position at maximum permissible distance withrespect to the bolt extension 30.

On the contrary at the time the locking shoes 9 are .within the sloping seats I9 (Fig. 1) each of them abuts frontally against a face 29 of the bolt 26 and the opposite face of the cooperating seat l0 and it rests against the side face of the adjacent extension 33 of the slider 32 which projects over the bolt extension 30; the breech closing parts of the firearm then are in their locked position.

The striker includes a stem [4 having an end pin l4 said stem i4 is connected with the slider 32 and extends throughout a central bore of the bolt 26 where a spring I5 is located, this spring abutting on a flange M" of the stem M at one of its ends and on a sleeve 38 fast in the bolt 26 at its opposite end.

The spring I5 is thus operative both to drive the striker forward and to move the slider 32 into its advanced position which corresponds with the 'bolt locked position.

The slider 32 is provided with a transverse hold the bolt 26 in open position and the striker spring cocked, said sear |9 being adapted to be released by means of a wedge trigger 29 I a firinggas outlet 25 from the barrel opens.

The bolt 26 has in turn on the path of the finger I8 a similar finger I8 which is engaged by the finger IS in its recoil stroke.

In the position of the parts shown in Fig. 1 the firearm receiver 2 is closed by the front face of the rod 21 of the bolt 26 located against the rear end of the bore of the barrel I Ihe breech bolt 26 is in turn locked. by the locking shoes 9 which abut on the transverse faces 29 thereof and are in turn engaged within the seats ll] of the receiver 2 said shoes 9 being restricted from coming out therefrom due to their abutment against the sides of the extensions 33 of the slider 32.

The breech is thus closed in a fully efiicient manner and its closing is the more reliable the greater the rearward thrust exerted on the bolt 21, 26 because said thrust is imparted to locking shoes 9 which are thus wedged intermediate the faces of the inclined seats l0 and the slider extensions 33.

In fact the force the cartridge base transmits to the bolt, 26 and to shoes 9 at the time a sho't is fired, is resolved into two components one of which acts on the receiver 2 and the other on the slider 32 in a direction perpendicular to the barrel axis, the second named components having the same line of action and opposed directions iii-respect of the two shoes '9 so that no torque is imparted to the receiver.

For opening the bolt 26, 21 the slider 32 is moved back; in the described construction such a back displacement is caused by the pressure imparted by the rod 2| which is moved back, immediately after a shot fired, by the action of the firing gases issuing from the barrel I through the duct 25 and operative on the bottom of the sleeve 23 at the time the bullet has moved past the orifice of said duct 25 in the fixed piston 24.

At the time a shot is fired the rod 2| thus recoils under the action of the shot firing gases and imparts a blow on the finger I8; the slider 32 is thus caused to recoil against the action of the striker spring l5 whilst the bolt 26 at first remains stationary due to the longitudinal gap intermediate said slider 32 and the bolt '26.

In' this operation due to the movement of the slider 32 along the bolt slot 35 the side abutments provided by the slider extensions 33 forthe locking shoes tare removed and. said shoes 9 slide along the sloping seats l0 under the action of bolt faces 29 on the shoe faces 31 due to firing gas pressure on the bolt 26, 21 and to the recoil action of the slider 32 on said bolt, said locking shoes thus finally taking a position in contact with the bolt extensions 30 (Fig. 2)

Then the bolt. 26 recoils against the spring 3 with slider 32 under the action of rod 2| and slider 32 to reach its positionin which the slider finger I8 is engaged behind the sear |9 (Fig. 2).

-To fire a shot a pressure is applied to the push button 39 to shift the trigger 29 and to remove finger |8 intended to cooperate with a sear 19 to the 'sear IS, the bolt 26 thus moving forward with the slider .32 under the action of the spring 3; at the time the bolt 26 stops in its forward end position theslide'r 32 further advances under the action of the striker spring l5 and the front faces of the extensions 33 thereof drive the shoes 9 in front thereto said shoes being finally caused to enter the sloping seats l0 connected with the receiver grooves 8.

The slider 32 may thusreach its most advanced position to drive the striker pin i4, I4 against the cap of a fresh cartridge fed in the barrel bore only after said shoes 9 have entirely released the path of the extensions 33- of the slider 32 and Accordingly the shot is fired'only at the time the bolt is fully closed and looked that is when the bolt 26 is engaged bythe shoes 9 which in turn abut against thesides of the slider extensions39. j

The breech is thus fully closed at the time a shot is fired and a cartridge-may be struck only after the bolt has been locked in closed position, all the requirements inherent to a regular and safe operation of an automatic firearm being thus satisfied. V I

g The above described result is obtained without parts operating with rotarymotion and'accordingly no member of the mechanism issubject to harmful torsional actions.

Further due to the restricted mass of the slider 32 any liability to rebound actions is removed. 7

While in the preferred example shown in' the drawingtwo locking shoes are provided, it is obvious that any other numberof such locking shoes maybe used. If more th'an two locking shoes are provided they should be. conveniently arranged in a symmetrical positionwith respect to the longitudinal axis of the barrel, thusavoiding unbalanced transverse strains. i

What I claim as my invention and desire to secure by United States Letters Patent 1. In a firearm,'a receiver and a barrel extending from said receiver, an-elongated breech bolt mounted to reciprocate in said receiver, said bolt having a slot, intermediate its ends and formed with a rearwardly opening socket, means for urging said bolt in a position to close said barrel, said means including a spring, one end of which spring bears against said receiver and the other end against said bolt in said socket, said receiver having in the internal surface of its walla longitudinal guideway having an extension in a direction inclined to the reciprocatory path of. said bolt, a slider mounted in said receiver and in said slot of said bolt, to reciprocate with respect to said bolt, bolt locking means wholly independent of said bolt and sliderfland mounted to movejin said receiver guideway alongthe pathof said bolt in said receiver, means on said lockingfnieans arranged to enter saidinclined extension of said guideway, and when so 'positionedgto hold said locking means engaged with said slider and said bolt to lock said bolt in its barrel closing position.

means urging said slider forwardly into a position adjacent to said inclined extension to move said locking means forwardly and then outwardly into said inclined extension and finally to hold said locking means in said inclined extension in bolt locking relationship, and means operated by a shot being fired for shifting said slider and removing it from looking position for the release of said bolt locking means.

2. In a firearm, a receiver and a barrel extending from said receiver, an elongated breech bolt mounted to reciprocate in said receiver, said bolt having a slot intermediate its ends and an axial bore in its forward end portion, and formed with a rearwardly opening socket, means for urging said bolt in a position to closed said barrel, said means including a spring, one end of which spring bears against said receiver and the other end against said bolt in said socket, said receiver having in the internal surface of its wall a longitudinal guideway having an extension in a direction inclined to the reciprocatory path of said bolt, a slider mounted in said receiver and in said slot of said bolt to reciprocate with respect to said bolt, a firing pin connected with said slider and extending through said bore of said bolt, bolt locking means wholly independent of said bolt and slider and mounted to move in said receiver guideway along the path of said bolt in said receiver, sloping lug on said locking means arranged to enter said inclined extension of said guideway and when engaged therein to hold said locking means engaged with said slider and said bolt to lock said bolt in its barrel closing position, means urging said slider forwardly into a position adjacent said inclined extension to move said locking means forwardly and then outward- 1y into said inclined extension and finally to hold said locking means in said inclined extension in bolt locking relationship, and means operated by a shot being fired for shifting said slider and removing it from looking position for the release of said bolt locking means.

ALESSANDRO GAL.

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