US3718998A

US3718998A - Sear lever for eliminating doubling

Info

Publication number: US3718998A
Application number: US00195600A
Authority: US
Inventors: T Hartog
Original assignee: Browning Industries Inc
Current assignee: Browning Industries Inc
Priority date: 1971-11-04
Filing date: 1971-11-04
Publication date: 1973-03-06
Anticipated expiration: 1990-03-06

Abstract

A SEAR LEVER FOR A DOUBLE BARREL FIREARM SINGLE TRIGGER FIRING MECHANISM INCLUDES A CONTROL SURFACE EXTENDING OVER THE LIFTING SURFACE OF THE SEAR LEVER WHICH COACTS WITH THE FIREARM''S FIRST SEAR, THE CONTROL SURFACE BEING JUXTAPOSED TO THE LIFTING SURFACE AT AN ACUTE ANGLE SUCH THAT THE FIREARM''S FIRST SEAR MOVES AGAINST THE CONTROL SURFACE UNTIL THE FIREARM''S INERTIA BLOCK MOVES THE SEAR LEVER AWAY FROM THE END OF THE FIRST SEAR DURING COUNTER RECOIL.

Description

March 1973 T. J. HARTOG 3,718,998

SEAR LEVER FOR ELIMINATING DOUBLING Filed Nov. 4, 1971 2 Sheets-Sheet l INVENTOR. Thomas J Harfog @MKJZM/Q ATTORNEY -March 6, 1973 T. J. HARTOG 3,718,998

SEAR LEVER FOR ELIMINATING DOUBLING Filed Nov. 4. 1971 2 Sheets-Sheet 2 INVENTOR. Thomas J. Har/og lQ-MM ATTORNEY United States Patent Office 3,713,998 Patented Mar. 6, 1973 3,718,998 SEAR LEVER FOR ELIMINATING DOUBLING Thomas J. Hartog, Ogden, Utah, assignor to Browning Industries, Inc., Morgan, Utah Filed Nov. 4, 1971, Ser. No. 195,600 Int. Cl. F410 11/10, 19/00 US. Cl. 42-42 R 12 Claims ABSTRACT OF THE DISCLOSURE A sear lever for a double barrel firearm single trigger firing mechanism includes a control surface extending over the lifting surface of the sear lever which coacts with the firearms first sear, the control surface being juxtaposed to the lifting surface at an acute angle such that the firearms first sear moves against the control surface until the firearms inertia block moves the sear lever away from the end of the first sear during counter recoil.

BACKGROUND OF THE INVENTION The firing of double barrel firearms such as shotguns is often controlled with a single trigger mechanism which fires each barrel individually on successive pulls of the trigger. For safe operation, the trigger mechanism should positively prevent firing of both barrels (i.e., doubling) on the first trigger pull. A disconnect or delay mechanism has been used for this purpose, the most common type of delay mechanism being an inertia block which pulls the firearms sear lever completely out of engagement with the sears which activate the hammers during much of the recoil sequence. However, during the first phase of recoil, as the firearm moves to the tear, the inertia block does not operate. If the shooter releases and then again pulls the trigger in this phase of the recoil, doubling can result. Accordingly, this invention provides a delay structure for double barrel firearms to prevent the sear lever from disengaging the first sear and engaging the second sear should involuntary trigger release and pull occur during the first phase or initial rearward movement of the recoiling firearm.

SUMMARY OF THE INVENTION In its broadest form the invention relates to an improved sear lever useful in a single trigger firing mechanism for a double barrel firearm. The improvement comprises means secured to the sear lever for positively engaging the firearms first sear during trigger pull and release until the sear lever is moved to a position remote from the first sear by the inertia block during counter recoil. Preferably, the means comprises a control surface extending over the lifting surface of the sear lever which coacts with the firearms first sear, said control surface being juxtaposed to the lifting surface at an acute angle, such that the firearms first sear moves against the control surface until the inertia block moves the sear lever away from the first sear during the counter recoil. Although the preferred acute angle between the lifting and control surfaces of the sear lever will vary among various firearms, normally between about 30 to about 80 degrees, an angle of about 70 degrees has given consistently good results in a popular gauge shotgun.

In some embodiments of the invention, biasing means are attached to the inertia block to urge the sear lever and inertia block to an operative position with respect to the firearms second sear after the counter recoil of the first barrel discharge. Other embodiments include biasing means to disengage the sear lever from the first soar in the event of a misfire or dry fire.

BRIEF DESCRIPTION OF THE DRAWINGS So that the invention may be more readily understood and carried into effect, reference is made to the accompanying drawings which are offered by way of example only and are not to be taken as limiting the invention, the scope of which is defined by the appended claims which obviously embrace equivalent structures.

FIG. 1 is a side elevation view of a portion of a single trigger mechanism of a double barrel firearm when the mechanism is cocked and ready to fire both barrels of the firearm. For purposes of clarity, the biasing spring in the trigger mechanisms inertia block is shown in phantom.

FIG. 2 is a side elevation view of a portion of a single trigger mechanism of a double barrel firearm after the first barrel has been fired.

FIG. 3 is a sectional view taken in the plane of line 33 of FIG. 1, looking in the direction of the arrows.

FIG. 4 is a side elevation view of the preferred sear lever of the invention. For purposes of clarity, hidden surfaces are shown in phantom.

FIG. 5 is a top plan view of the sear lever shown in FIG. 4.

FIG. 6 is a front elevation view of the sear lever shown in FIG. 4.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENT A single trigger mechanism for a double barrel firearm generally includes a trigger 10 pivotally mounted in a conventional fashion to the firearms frame 12 with a pin 14, a sear lever 16, an inertia block 18, a first sear 20 and a second sear 22. The sear lever 16 is pivotally attached to the inertia block 18 with sear lever pin 24 and the inertia block 18 is in turn pivotally attached to the firearms frame 12 with inertia block pin 26. Accordingly, when trigger 10 is successively pulled, released, and then again pulled, sear lever 16 first lifts sear 20 and then the second sear 22 to successively release the firearms hammers (not shown in the drawings) in conventional fashion, thereby successively discharging the barrels of the firearm.

As best shown in FIGS. 4-6, sear lever 16 is formed with

lifting platform surfaces

28 and 30 positioned on opposite sides of an elongated center support member 32. Lifting surface 28 is intended to engage first sear 20 while lifting surface 30 is intended to engage the second sear 22.

Center member 32 may, of course, be shaped in any configuration so as to properly coact with trigger 10, e.g., with the outwardly projecting lip 34 shown. A bore hole 36 is provided at one end of center member 32 to accommodate the sear lever pivot pin 24 (FIG. 1), as heretofore described.

To prevent the end 21 of first sear lever 20 from lifting away from lifting surface 28 prior to sear lever 16 being pulled away from the end 21 during recoil, a control surface 38 is provided above lifting surface 28, preferably at an acute angle B (FIG. 4), as illustrated, to form a detent sized to receive a predetermined portion of one end 21 of the first sear 20. Ideally, the lifting surface 28 and control surface 38 are formed as intersecting surfaces in block 40, shown fixedly secured to one side of center support 32. Biasing means, such as inertia block spring 42 (FIG. 1) coacts with inertia block 18, sear lever 16, and frame 12 to urge sear lever 16 forward toward

sears

20 and 22. Preferably, end 21 of sear 20 which contacts lifting surface 28 and control surface 38 is shaped to substantially conform with said surfaces. The acute angle of the faces of the sear levers surfaces herein described and the end of the first sear is selected such that sear lever 16 tends to disengage sear end 21 of the first sear 20 under the influence of the downward pressure applied by the inertia block spring 42 when the firearm is not recoiling. It is usually desirable to provide supplemental biasing means, such as the spring 44 shown, to ensure disengagement of the sear lever 16 from the first sear 20 in the event no recoil occurs after the trigger is pulled. This expedient ensures automatic mechanical operation to fire the second barrel when the first barrel fails to shoot or is dry fired.

It is to be noted that while it is preferred that

surfaces

28 and 38 be substantially plane surfaces, it is within the scope of the invention that these surfaces be curved, and particularly surface 28. When this is the case, acute angle B is formed by the intersecting tangents formed by the end 21 of sear 20 at the points of contact with

surfaces

28 and 38.

In operation, when both hammers of a double barrel firearm are cocked, the end 21 of scar 20 is positioned between

surfaces

28 and 38 of the sear lever 16. Accordingly, when trigger is pulled, sear lever 16 is lifted by the trigger wherein sear 20 is also lifted with surface 28 to release the first hammer which fires the firearms first barrel. During the resulting recoil sequence the firearm is urged rearwardly and the shooter may involuntarily release and then pull the trigger. If this occurs, the end 21 of sear 20 remains positioned between lifting surface 28 and control surface 38 because of the acute angle formed between said

surfaces

28 and 38. When the initial recoil sequence has been completed, i.e., the firearm is no longer moving rearwardly, inertia block 18 pivots on pin 26 to move in a rearward direction which pulls sear lever 16 completely out of engagement with sear 20 (see FIG. 2). Thereafter, biasing spring 42 urges the inertia block with attached sear lever 16 to move forward towards the second sear 22 so that the sear lever lifting surface is ultimately positioned under said second sear 22. The second barrel of the firearm is now ready to be fired by again pulling trigger 10 which lifts sear 22 to release the second hammer used to fire the firearms second barrel.

For purposes of clarity, the term first phase of recoil as used herein refers to the phase of the recoil where the firearms frame moves rearwardly after being discharged. The term counter recoil as used herein refers to the phase of the recoil where rearward movement of the firearms frame has substantially terminated but where other structure, notably the inertia block, is still in movement.

I claim:

1. An improved sear lever for a double barrel firearm having a single trigger firing mechanism using first and second sears to control firing of the barrels of said firearm, the improvement comprising:

an elongated lever member;

first lifting platform means secured to said lever member for coacting with one end of the firears first sear; and

control surface means juxtaposed with respect to said lifting platform to form a detent between said lifting platform and said control surface means sized to receive a predetermined portion of said one end of said first sear.

2. The improved sear lever of claim 1 wherein second lifting platform means are secured to said lever member for coacting with one end of the firearms second sear.

3. The improved sear lever of claim 1 wherein said first lifting platform is a substantially plane surface and said control surface means forms a substantially plane surface which intersects said first lifting surface at an acute angle.

4. The improved sear level of claim 3 wherein second lifting platform means are secured to said lever member for coacting with one end of the firearms second sear.

5. In a double barrel firearm having a single trigger firing mechanism using first and second sears to control firing of the firearms barrels,

an inertia block pivotally attached to the firearm's frame;

an elongated lever pivotally attached proximate one end to said inertia block;

first lifting platform means secured to said lever member for coacting with one end of the firearms first scar; and

6. The double barrel firearm of claim 5 wherein second lifting platform means are secured to said lever member for coacting with one end of the firearms second sear.

7. The double barrel firearm of claim 5 wherein said first lifting platform is a substantially plane surface and said control surface means forms a substantially plane surface which intersects said first lifting surface at an acute angle.

8. The double barrel firearm of claim 7 wherein second lifting platform means are secured to said lever member for coacting with one end of the firearms second sear.

9. The double barrel firearm of claim 5 including biasing means mounted to coact with said firearm frame, inertia block and lever member to urge said lever member towards said first and second sears.

'10. The double barrel firearm of claim 9 wherein second lifting platform means are secured to said lever member for coacting with one end of the firearms second sear.

II. The double barrel firearm of claim 10 wherein said first lifting platform is a substantially plane surface and said control surface means forms a substantially plane surface which intersects said first lifting surface at an acute angle.

12. The double barrel firearm of claim 10 including biasing means mounted to coact with said firearm frame and lever member to urge said sear lever out of engagement with said first sear when no recoil occurs in response to pulling of the trigger to fire the first barrel of said firearm.

References Cited UNITED STATES PATENTS 1,268,760 6/1918 Novotny 42-42 R 1,519,589 12/1924 Miller 42-42 R 2,295,941 9/1942 Fahlen 4242 R BENJAMIN A. BORCHELT, Primary Examiner C. T. JORDAN, Assistant Examiner