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Publication numberUS2487971 A
Publication typeGrant
Publication dateNov 15, 1949
Filing dateApr 23, 1946
Priority dateApr 23, 1946
Publication numberUS 2487971 A, US 2487971A, US-A-2487971, US2487971 A, US2487971A
InventorsJenkinson Robert L
Original AssigneeMarlin Firearms Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Trigger-locking means
US 2487971 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Nov. 15, 1949 R. 1.. JENKINSON 2,487,971

TRIGGER LOCKING MEANS Filed April 23, 1946 hue/flaw 5y Robe/f A. derzhksa/z Patented Nov. 15,1949

UNITED STATES PATENT OFFICE 2,487,971 TRIGGER-LOCKING MEANS Robert L. J enkinson, New Haven, Conn., assignor to The Marlin Firearms (30., New Haven, Conn., a corporation of Connecticut Application April 23, 1946, Serial No. 664,240

1 Claim.

The present invention relates in general to firearms and more especially to firearms commonly known and classified as shotguns, the par- ,ticular shotgun herein shown and described being a double-barreled shotgun of the over-and-under type.

Shotguns having double-barrels may employ two sets of fire-control mechanism including a trigger for each barrel. In using shotguns of this type in the field, a shooter quite generally engages both the first and second fingers of his hand with the front and rear triggers respectively of the shotgun in order to be ready to fire both barrels in rapid succession. However, it happens, not infrequently, that the shooter will inadvertently pull both triggers simultaneously, which not only wastes ammunition but produces an extremely severe recoil blow against the shooters shoulder. Much has been written by way of explaining the cause of doubling, and in general it may be said that the recoil and counter-recoil of the firearm plus the involuntary flinching and excitement of the shooter are contributing factors which may cause the simultaneous and inadvertent release of both triggers.

An object of the present invention is therefore to provide improved means for preventing the release simultaneously of both triggers of a doublebarreled shotgun.

A further object is to provide improved triggerlocking means for a double-barreled shotgun having two triggers, the improved trigger-locking means being adapted to automatically lock one trigger when the second trigger is pulled.

With the above and other objects in view, as will appear to those skilled in the art from the present disclosure, this invention includes all features in the said disclosure which are novel over the prior art.

In the accompanying drawings, in which certain modes of carrying out the present invention are shown for illustrative purposes:

Fig. 1 is a fragmentary side elevation partly in section of the frame structure of a double-barreled shotgun, including the improved triggerlocking means of this invention and a portion of the pistol grip;

Fig. 2 is a fragmentary plan view partly in section on line 2-2 of Fig. 1;

Fig. 3 is a fragmentary sectional elevation on line 3--3 of Fig. 1, showing both triggers in their normal positions;

Fig. 4 is similar to Fig. 3 but shows one of the triggers in its displaced position;

Fig. 5 is a perspective view of the left trigger;

Fig. 6 is a perspective view of the right trigger; and

Fig. 7 is a perspective view of the spacer.

In carrying out the invention, an exemplary embodiment of which is shown in the drawings, the frame I!) of the firearm has, at its forward end, a pivot-pin H for pivotally supporting the double-barrels (not shown) of the firearm, the barrels being of the over-and-under type adapted to be dropped at their muzzle-ends and raised at their breech-ends for inserting cartridges into the chambers of the barrels. The stationary breech-plate of the frame [0 is indicated generally at I2 and is an integral part of the frame structure ID. The trigger-guard I4 is shown as a separable element pinned at its forward end to a portion I5 of the frame structure, and secured at its rear end to the frame ID by a screw I5 or similar fastening-means. The usual barrel unlocking-latch is shown at I! pivotally mounted adjacent the crown of the frame l9. Rearwardly of the latch I1 is the conventional manually-operated safety I8.

The frame structure l0 also includes integral upper and lower tangs l9 and 20 respectively, joined at their rear ends by a post 2| which is integral at its opposite ends with the rear ends of the tangs l9 and 20. Between the rear post 2| and the stationary breech-plate l2 of the frame, is an intermediate-post 22 which is adapted, in a conventional manner, to slidably support the rear ends of the spring-loaded firing-pins (not shown) and to provide pivotal support for the triggersears, the latter being connected to the rightand left-hand triggers 23 and 24 respectively by searconnectors 25 and 26 respectively. Suitable cover-plates are provided on opposite sides of the tangs l9 and 20 of the frame structure [0, as indicated at 41, in Figs. 1 and 2.

The triggers 23 and 24 comprise substantiallyfiat relatively-thin leaf-members (see Figs. 5 and 6) and are substantially identical in shape except that the finger-grip 21 of the right-hand triggermember is nearer the forward end of the trigger than the finger-grip 28 of the left-hand trigger. The trigger-members are provided at their forward ends with pivot-pin holes 29 and 30 respectively, and adjacent their rear ends with notches 3| and 32 in their upper edges to receive the lower ends of the respective sear-connectors 25 and 26. Rearwardly of the notches are elongated apertures 33 and 34 respectively, the longitudinal axis of each aperture being disposed substantially transversely to the longitudinal axis of its triggermember. The longitudinalapertures 33 and 34 are adapted to receive a fixed pin 35 and, as herethe lower tang 26 of the frame structure II] by a transverse-pin 39 which is mounted at its opposite ends in axially-aligned apertures at the forward end of the lower tang, thepin 39 passing through the axially-aligned holes 29 and 30 of the triggers. The triggers are thus arranged in substantially-spaced, parallel relationship in the aperture 38. The triggers .are adapted to be separated by a relatively-thin spacer-plate .40 which, as shown in Fi 7, is apertured at its forward end, as at 4|, to accommodate the transverse trigger pivot-pin 39; and adjacent its rear end, as at 42, to receive the fixed pin 35, the latter bei g mounted in axially-aligned apertures of the tang of the frame structure transversely of the longitudinal axis of the rectangular aperture 38. The spacer-plate 40 is thus held securely in the rectangular aperture 38 substantially coincident with its longitudinal axis, the triggers 23 and being free to move relative to the spacerplate 40 by provision of the elongated reliefapertures 33 and 34 respectively through which the fixed pin 35 passes.

Although in the present embodiment the spacer-plate 40 is shown as a separate element, it will be understood that the plate 4.0 may be an inte ral part of the lower tang 20 of the frame structure.

As shown in Fig. 7, a third transverse aperture 43 is provided in the rear end of the spacer-plate 40. When the two triggers and the spacer-plate are assembled in their normal positions in the frame structure, the transverse aperture 43 is in axial alignment with the two shallow concave recesses in the inner faces of the respective trig gers, as shown in Figs. 2 and 3. The diameter of the aperture 43 in the spacer-plate 40 and the diameters of the circular recesses 36 and v3'! of the triggers are substantially equal, the aperiture 43 and recesses 36 and 31 being adapted to receive a trigger-locking ball 44 which is of a diameter to make a smooth sliding fit in the apers ture 43 and the recesses 36 and 31.

Referring to Fig. 3 in which the two triggers are in their normal positions, the axially-aligned recesses of the triggers and the aperture 43 in the spacer-plate form a closed pocket 45 for the ball 44, the latter being free to move transversely from the left to right or from right to left therein. The thickness of the spacer-plate 40 and the depth of each recess bear a predetermined relationship to the diameter of the ball such that when the ball is in either its extreme rightor left-hand position in the pocket, the periphery of the ball will clear the circumferential edge of the oppositely-disposed recess of the left and right triggers respectively. That is to say, the

minimum effective length of the pocket 45 must be slightly greater than one and onehalf times the diameter of the ball. The effective length of the pocket shall be understood to be the distance measured between the locus of all points on the concave surface of the recess 36 engaged by the spherical surface of the ball, and the locus of all points on the conical surface of the recess 3'! engaged by the spherical surface of the ball. The maximum efiective length of the pocket 45 is a controlling factor in accomplishing the automatic displacement of the ball from either of its extreme positions in the pocket, the prerequisite being that the effective depth of each recess 36 and 31 shall be slightly less than the radius of the ball, so that when the ball is seated in the recess the center of mass of the ball, which coincides with its center of gravity will lie slightly outside of the circumferential edge of the recess. The term effective depth as applied to the recesses in the triggers shall be understood to mean the distance measured between the locus of all points on the conical surface of the recess engaged by the spherical surface of the ball and the circumferential edge of the recess.

In the operation of the triggers of the firearm, assuming the right and left-hand triggers are in their normal positions, as indicated in Fig. 3, and that the trigger-locking ball 44 is seated in the recess 3'! of the left-hand trigger 24, the right-i hand trigger 23 may be pulled without interference from the trigger-locking ball 44. Similarly, if instead of pulling the right-hand trigger 23 the left-hand trigger 24 is pulled, the wiping or camming action between the circumferential edge of the recess 31 of the left-hand trigger and the spherical surface of the ball will sufiice to move the ball out of the recess 31, which action is effected by engagement of the edge of the recess with the spherical surface of the ball in a plane parallel to but offset from a plane through the center of gravity of the ball, the ball being free to move transversely across the pocket into the recess 36 of the right-hand trigger 23. A similar action takes place when the ball rests initially in the recess 36 of the right-hand trigger 23, as shown in Fig. 4,

Assuming, however, that the ball rests. in the recess of the right-hand trigger and that the lefthand trigger '24 has been pulled and held in its retracted position asshown in Fig. 4, its recess 31 is then out of alignment with the adjacent end of the transverse aperture 43 of the pocket 45, thus presenting the inner substantially-plainer surface of the trigger-member 24 opposite the adjacent end of the transverse aperture 43, as a consequence of which the ball 44 is unable to move out of the recess 38 of the right-hand trigger 23 and will thereby efiectively lock the righthand trigger until the left-hand trigger 24 has been released and returned to its normal position. A similar action takes place to automati cally lock the left-hand trigger when the righthand trigger has been pulled. V V

The above described trigger-locking device is of relatively-simple construction embodying but one moving part and is adapted to be readily mounted in shotguns of the type described without necessitating any substantial alterations in the trigger-mechanism oi the firearm, and at a minimum cost.

The invention may be carried out in other specific ways than those herein set forth With out departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claim are intended to be emerged ih a spacer-plate fixedly secured in said frame between said trigger-members and having an aperture extending transversely therethrough substantially in axial alignment with the respective blind-recesses of said trigger-members, the said aperture of said spacer-plate and the respective blind-recesses of said trigger-members forming a substantially-transverse pocket extending between said trigger-members, and a ball mounted to roll freely in said pocket, the diameter of said ball corresponding substantially to the diameter of said pocket and to substantially two-thirds the transverse dimension thereof whereby movement of one trigger-member vertically with respect to the opposite trigger-member and to said transverse aperture serves to cam said ball out of the blind-recess of said one trigger across said aperture into the blind-recess of the opposite triggermernber thereby automatically locking said 0ppositely-disposed trigger positively against movement while the blind-recess of said one trigger is out of alignment with the said transverse aperture.


REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATESVPA'I'ENTS Number Name Date 853,229 DeLand May 14, 1907 882,091 Balloco Mar. 17, 1908 1,463,328 Lewis Feb. 8, 1922 1,830,213 Stiennon Nov. 22, 1930 FOREIGN PATENTS Number Country Date 427,819 France June 7, 1911

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US853229 *Dec 26, 1906May 14, 1907Harry H CoburnTrigger mechanism.
US882091 *Dec 4, 1906Mar 17, 1908Itala Fabbrica Di AutomobiliSpeed-change mechanism.
US1463328 *Feb 8, 1922Jul 31, 1923Lewis Otto LeroyGear-shifting device for transmissions
US1830213 *Nov 22, 1930Nov 3, 1931Winchester Repeating Arms CoSelective trigger-mechanism for firearms
FR427819A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5784819 *Mar 3, 1997Jul 28, 1998Roper; Richard BlairTrigger safety lock
US5946841 *May 8, 1998Sep 7, 1999Roper; Richard BlairLocking device
U.S. Classification42/70.6
International ClassificationF41A19/00, F41A19/18
Cooperative ClassificationF41A19/18
European ClassificationF41A19/18