US2375381A

US2375381A - Trigger mechanism

Info

Publication number: US2375381A
Application number: US502658A
Authority: US
Inventors: Pale Paul
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-09-16
Filing date: 1943-09-16
Publication date: 1945-05-08
Anticipated expiration: 1962-05-08

Description

May 8, 1945. P, PALE 2,375,381

TRIGGER MECHANISM Filed Sept. 16, 1943 2 Sheets-Sheet 1 gram fay] fale ma ,8, 1945. PALE 2,375,381

TRIGGER MECHANISM Filed Sept. 16, 1943 2 Sheets-Sheet 2 Paul Pale Patented May 8, 1945 UNHTED STATES PATENT OFFICE TRIGGER MECHANISM Paul Pal, Wilkes-Barre, Pa. 1

Application September 16, 1943, Serial No. 502,658

14 Claims.

This invention relates to trigger mechanism for firearms, and more particularly to such mechanism wherein a long trigger stroke is utilized and the point within the limits of the stroke at which the firing mechanism is tripped varies indeterminately and infinitely.

Modern firearms are designed to provide infinitesimal movement of the trigger from cocked to tripped position. Novicesare taught by expert marksmen that the trigger must not be pulled but squeezed very gradually. In other words, the firing is not accomplished by moving the trigger through an appreciable arc, but rather by a gradual increase of pressure against the trigger until it suddenly trips and is -free. To increase the safety factor, rules. have been established for the majority of competitive meets which bar the use of any fire arm requiring less' than a certain specified minimum trigger pressure to fire. This trigger action, light or heavy, presents many hazards to good marksmanship.

First, the gradual, smooth increase in pressure upon the trigger is difiicult to attain, and to most persons comes only through long practice. Uneven or jerky increase in pressure will cause the gun to be deflected from the target and thus spoil the shot. Second, at the instant of release, the trigger mechanism is relieved of its load and the trigger moves freely. The pressure put upon the trigger to fire the gun causes the trigger to snap back quickly to its limit of movement. On those rare occasions, with mode rn ammunition, when a shell hangs fire for a brief interval; the sudden movement of the trigge r after release will cause the gun to deflect and be off the target when the shell fires belatedly. Third, and most important, expert and experienced marksmen learn the action of their firearms after but a few shots so that they subconsciously know or sense the instant that the trigger is ready to release. Only a comparative few are so constituted that they can prevent a slight involuntary flinch in anticipation of the explosion to follow. This also spoils the aim. Even though the marksmanbecomes proficient in the operation of the trigger, he must learn to control his own reactions. He must keep his nerves'under such rigid control that the human tendency to fiinch in anticipation of the noise or shock will be overcome.

The object of this invention is to provide trigger mechanism which will overcome these mental as Well as mechanical handicaps to good marksmanship by incorporating means to give a long equalized trigger pull before and after release, and an indeterminate point of fire that varies infinitely within limits less than the full, trigger stroke and is impossible to predetermine,

attachment for stock firearms, the mechanism including an auxiliary trigger and accompany-g ing mechanism to be secured to the firearm to actuate the existing trigger, or may bebuilt into the gun as a part thereof and have a single trigger. I I

A further object of the invention is to provide in such a device means whereby the auxiliary trigger may be moved throughout its full range when the safety is on or the gun is jammed without damage to the firearms mechanism or that of the attachment. It is also contemplated that in the event of failure of a portion of the mechanism in the attachment, an emergency firing of the gun may be accomplished by actual contact of the auxiliary trigger with the existing trigger if the trigger pull is continued.

The inventive concept includes means adapted v to be applicable to any type trigger actuated firearm regardless of the trigger movement of the firearm as it is being cocked.

Broadly, the object of the present invention is to negative the probability of muzzle deflection during firing of the firearm by providing means to ensure smooth trigger operation and provide for an infinite number of points of fire so that the explosion will come as a surprise to avoid anticipation.

It is an object of the invention to provide means whereby an instructor may control the firing of the gun while standing far enough away to permit full freedom of movement and vision to the pupil.

Other objects of the invention will become apparent from the following specification taken in conjunction with the drawings which accompanyand form a part of the specification and throughout the several figures of which the same characters of reference are used to denote identical parts throughout.

In the drawings:

Figure 1 is a side elevational view of an automatic pistol showing the invention in the form of an attachment;

Figure 2 is an enlarged side elevation of a portion of a gun with the cover plate of the attachment removed;

Figure 3 is a view similar to Figure 2 showing parts in their position after the gun has fired and the trigger is on its return stroke;

Figure 4 is a vertical section taken on the line 4--4 of Figure 2;

Figure 5 is a horizontal section .taken on the line 5-5 of Figure 2;

Figure 6 is a perspective view of the trigger actuating unit;

Figure 7 is a detail view of a modified form of fulcrum cam actuating means;

Figure 8 is a view similar to Figure 2 showing the mechanism as adapted for use with a gun having a diiferent trigger movement;

Figure 9 is a perspective view of a gun showing remote control means for firing the gun;

Figure 10 is a fragmentary section through the case showing the modification necessary for the use of remote control;

Figure 11 is a fragmentary section taken through the remote control means at right angles to the showing in Figure 10.

Referring to the drawings in detail and first adverting to that form of the invention shown in Figures 1 to 6, the invention is shown as applied to an automatic pistol I. It is to be understood that the automatic pistol is merely illustrative of automatic guns in general, or any 1 firearm having an equivalent trigger movement.

In Figures 1 to 6, the invention is in the form of an attachment 2 to be secured to the side of the gun by any appropriate means and in the most desirable position, on the gun illustrated, above and adjacent the'trigger guard. It comprises a small case 3 having a base plate 4 and side walls 5. A cover plate 6 completes the case and protects the mechanism which the case houses.

Near the lower right hand corner of the case,

as viewed in Figure 2, a stud 1 projects outwardly from the base plate to form a pivot for a trigger actuating plate 8. Preferably, although not necessarily, stud I is in axial alignment with the pivot for the trigger 9 of the gun. The trigger actuating plate 8 has a body portion In generally triangular in shape, and a depending trigger engaging arm I extending downwardly from the body portion adjacent the pivot l. The trigger engaging arm passes through an opening 4| in the wall of the case and is offset laterally as at |2 below the body of the gun and within the circle of the trigger guard to permit the arm to lie fiat along the side of the trigger. A lip |3 at the lower extremity of the arm H is bent at right angles to the plane of the arm H to overlie the front of, and to apply pressure to, the trigger 9 at the tip. The forward portion of the base has a tongue struck out and split All to form an upstanding ear l4 and a rearwardly extending lug l5 passing over the edge of the trigger actuating plate to prevent the plate from moving out of its normal plane of movement.

A second plate I1 is pivoted to the trigger actuating plate 8 by means of pin I8. A- portion of plate ,l'! is bent upward and over the plate, as at |9, and a shaft 20 extends from the arm I9 to the plate I! and carries an irregular shaped fulcrum cam 2|. The irregularities of the cam have been greatly exaggerated in the drawings to graphically illustrate the principle of the invention, but, as a matter of fact, the cam will be much more nearly round and the depressions very slight.

Trigger actuating plate 8 has an opening 22 through which a stud 23 passes. Stud 23 is carried by the case base plate and forms a pivot for an auxiliary trigger 24. The lower end of trigger 24 passes through the opening 4| and is offset laterallly, as at 25, to position the finger piece 26 in substantially the same plane as the trigger 9. Trigger 24 has an arcuate portion 21 to fit around the fulcrum cam and a bearing point 28 to engage the cam when the trigger is actuated.

Upstanding lugs 29 and 30 on the trigger actuating plate 8 and second plate ll, respectively, form terminals to which are connected the opposite ends of the spring 3|. Under ordinary circumstances, plates 8 and H act together as a single unit, the spring 3| being of suflicient strength to hold the plate I! against the stop 32 projecting upwardly from the plate 8.

Pivoted to the base plate of the case at 33 is a latch member 34 provided with a sloping shoulder 35 to cooperate with a shoulder 36 provided at the edge of lug 28, as will be hereinafter described. Latch 34 is biased by a spring 31 for movement in a clockwise direction. The latch is also provided with a cam face 38 cooperating with a nose 39 on the trigger 24 for returning the latch to its normal inoperative position.

A spring 40 connects the upstanding ear M to the trigger 24 to hold the trigger in its forward position. The spring is attached to the trigger 24 at such a position that the spring must be deflected from its straight line position in order to pass around and frictionally engage the fulcrum cam 2|.

When the auxiliary trigger is actuated, it swings around its pivot 23 and the point 28 presses against the fulcrum cam 2| and forces the cam and the attached plate I! downward. The spring 3| is of suflicient strength to maintain plates I7 and 8 in their relative positions so that they operate as a unitary member, and when plate I! is forced downward plate 8 moves down around its pivot 1, causing the trigger 9 to move and so fire the gun. Trigger actuated plate 8 must move to a certain point in order to cause the trigger 9 to release. Stop screw II is adjusted to stop the movement of the plate when this point is reached. During its rearward movement, auxiliary trigger 24 has its bearing point 28 in contact with the fulcrum cam 2| and there is a rotating motion of the bearing point 28 upon the cam 2| as the plates move downward. As cam 2| has an irregular outline, the length of the stroke of the auxiliary trigger will vary depending upon the surface of the cam 2| contacted by bearing point 28. Spring 4|! draws the auxiliary trigger forward until it strikes the end of opening 4|. Therefore the auxiliary trigger always starts its stroke from a fixed point. The plate 8 has a positive limit at the end of its downward movement. The particular portion of cam 2| which strikes the trigger will determine the upward limit of movement of the plate. In this manner the amount of downward movement the plate will have will be varied. As the trigger moves the plate, its stroke is proportionately varied. If the face 28 contacts a high point in the cam. the trigger stroke will be relatively short, and if it contacts a low point on the cam, the trigger stroke will be proportionately increased. It is obvious that intermediate points will vary the stroke in accordance with their distance from the center of the cam.

amass-1w As the trigger is drawn backward; the nose 39 on-the upper portion or the-trigger will leave of the spring 3! untilits-upper surface strikes the under side of the shoulder 36. As the-trigger continues to move rearwardly rocking the" plate 3, the shoulder 36 will'move' forward, freeing the shoulder 35 and permitting the latch to rise be-r hind shoulder 36; As the shoulder 35 slopesj the rise is gradual and the latch becomes fu11y'en-" gaged just about the time the plate 8 has reached its limit of movement. The shoulder 35will hold the plate in its downward position, preventing its return, at any point after its initial engagement, so that if the' ma'rksman should-decide not to fire, the cam will have a' new setting the'next time thetrigger is pulled.

The latch-mechanism is provided to hold the plate downward while the auxiliary trigger returns to its position of rest" under the influence of the"spring 40, In this manner the auxiliary trigg'er'isspac'ed from the fulcrum cam 2i during its return swing and the cam is free to be rotated by the frictional bearingof the convolutions of' the contracting spring 40 against its periphery. v

F-ulcrum cam 2| is rotated a little in clockwise direction during the firing stroke'b'y contact with the auxiliary trigger, and it will be obvious that during the firing stroke the frictional bearing of the. trigger against the cam will prevent its oppo" site rotation by thespring 40. The cam will be moved by" the spring on the return stroke when thi pressure is released by means of the latch holding the plate in its downward position. Thus thecam will rotate in a clockwise direction only. This will not provide a positive drive to rotate the" cam and it may be rotated more or less, depending upon the slippage between spring and carh and the length of stroke of the auxiliary trigger. This is true whether the gun is actually fired or not.- This enhances the value of the device, as it renders the firing point even more indeterminate than would be the case if the cam were positively rotated through a set degree of arc each time'the gun was fired. By this arrangement an infinite movement of settings is provided between the highest and lowest points of the cam. I

Just before the auxiliary trigger 24 reaches the limit of its forward swing, the nose 39 contacts cam face 38 of the latch and rotates the latch' in a counterclockwise direction, releasing the plate 3 andpermitting it to return to its position of rest, which position is determined by the cam 2| striking the trigger bearing point 28. Spring 40' serves the mp1 function of returning the auxiliary trigger to its inoperative position,- rotating the cam 21, and drawing the plates 8 and IT back to their inoperative position. The two plates 8 and H, as has been described, function as a single plate when all of the mechanism is in working order. If, however, the safety lock of the gun is on, the gun trigger 9 is immovable. If some means were not provided to compensate for this, actuation of the auxiliary trigger 24 might cause breaking or straining of mechanism. For this reason, two plates are providedpivoted as at I8 50 that should the gun be locked or mechanism jammed, plate I'l may move downward in its usual manner. but plate 8 will remain stationary, the spring 3| lengthening to permit this movement. When the auxiliary trigger is released, the plate I! will return to its former position; which position" is determined by the cam 21' abutting the trigger. spring t r has the additional'fun'ctiori of providing smooth continuation'of auxiliary trigger pull beyondfiring'point' when the gun trigger has released, and itsre= sistance has greatly lessened suddenly. The tension of spring 3| added to that of spring 4Bwill preserve a uniform pull.

This structure provides a longitudinal stroke throughthe limits of which the pressure is substantially uniform'. The firing will take place at an indeterminate point in the stroke'with nothing totindicate to the marksman when thefiring is to take place and there is no sudden drop'in' the pull of the auxiliary trigger after gun has fired. The first indication he'will have that the firing mechanism has been released will be the recoil and sound of the explosion. Any phy-sical'reaction or fiinching which may then occur will not spoil the shot as the bullet has by that time left the gun.

If the mechanism should break, the user of the gun may still fire it by continuingthe backward stroke of the auxiliary trigger until it contacts the face of trigger 9 and by actual pressure moves the gun'trigger' 9.

A slight modification of the above structure is shown in Figure 7. wherein a cam follower t2" is pivotally connected to the auxiliary trigger 24 as at l3 and provided with a downwardly extending arm 44 to which the end of the spring Ml is attached. .The pull of spring will keep the long arm 45' of the follower tight against the surface of the cam and the friction between the follower and the cam will cause the cam to rotate on the return stroke of the auxiliary trigger. Such a device as this would be used primarily in the gun of an expert, where even the almost imperceptible sound of the convolutionsof the spring rubbing against the surface of the cam might give some indication as to when the firing point is about to be reached.

In Figure 8, the device is shown as applied to a revolver. A slightly modified mechanism must be supplied as the trigger action of a revolver is difierent from that of an automatic. Substantially the same movement of the trigger takes place to release the firing mechanism, but the trigger is moved forward when the gun is fired and then moves backward a considerable distance as the hammer isdrawn back. This is a necessary movement involved in the rotation of the cylinder or to cook the hammer. Consequently, provision must be madein the attachment to permit the trigger to follow its regular cycle of movement. This is accomplished by forming the plate 8 in two sections Z6 and 41, the twosections being locked for unitary movement when the gun is fired, by means of a latch 48'; Latch 4-8 is pivotally connected to the main portion of plate 8 as at 49 and is biased towards latching position by means of a spring 50. The latch has a relatively short arm 5| extendingat the opposite side of the pivot from the keeper, which lever is beveled at its upper edge for cooperation with a cam 52 fixed to pivot upon the auxiliary trigger 24. Cam 52 is held outward against a stop 53 by means of spring 54. When the auxiliary trigger is moved, cam 52 will slide over cam 55 of the latch, and as the latch is in position holding the two parts of the plate 8 together, the revolver trigger will be actuated and the gun fired. As the auxiliary trigger 24 returns to its position of rest, the cam 52, due to its frictional engagement with the cam face 55, will swing out-' ward around its pivot, thus preventing its passing the latch on its return without first moving the latch about its pivot. This will release the trigger section ll of the plate 8 and allow the revolver trigger the freedom of movement necessary to follow -its regular cycle as the gun is cooked.

As shown in Figures 9, 10 and 11, the present invention lends itself ideally to the use of remote firing control by instructors. The bottom 4 of the case may be extended slightly, as shown at 5B, and provided with a substantially square opening 51, and the plate 8 may have a similar extension 58 and opening 59. The housing will also have to be dropped to provide opposite openings 60 which form bearings for a remote control rod 6!. Rod 6| may be made in sections coupled together by flexible tubing 62, and carry at its end a metal control shaft 63. The control shaft has circular ends 64 to seat in the openings Gil in the housing when the rod has been inserted in place, and the rod is clamped in position by means of a knurled nut 55. An indicating arrow 66 is attached to the opposite end of the metal control rod and serves to show the position of the shaft in the casing. The central portion of the shaft is cut away, as at 61, leaving only a quadrant of the shaft as at 68. The central portion of the shaft passes through the openings 51 and 59 in the extensions 56 and 58, respectively, with the shaft bearing against the sides 69 and T0 of the opening 59. When the auxiliary trigger 24 is 'moved, only the plate I! will move, as the central portion of the control rod 63 prevents movement of the trigger actuating plate 8. At such time as the instructor desires to fire the gun, the rod is rotated to move the portion 58 to the opposite side of the opening 59 and the contraction of the spring 3| will move the plate 8 and actuate the trigger to fire the gun.

It is to be understood that the invention is adaptable either to an attachment or as a part of the firearm. It, is only necessary that the plate 8 be in operative connection with that part of the firearms mechanism which releases the firing mechanism. When it is to be attached to a firearm, the firearms trigger will be the firing mechanism release, necessitating the use ofan auxiliary trigger, but when built into a firearm will be connected to only that portion of the trigger which is inside the firearm, the remainder of the trigger being eliminated.

Although certain specific, practical embodiments of the invention have been shown and described, it is to be understood that the inventive concept is capable of many adaptations and changes from the structure shown and the invention is to be limited only by the scope of the appended claims.

Having thus described my invention, what I claim is:

1. Trigger mechanism for firearms comprising, a trigger, firing mechanism release means, a member to operate said firing mechanism release means, and pivoted means having a perimeter which varies in distance from the pivot interposed between said trigger and said member for transmitting movement of said trigger to said member, said means being shiftable where by the length of the trigger stroke is varied on successive operations of the trigger.

2. Trigger mechanism for firearms comprising, a trigger, firing mechanism release means, a member to operate said firing mechanism release means, a pivoted cam having a perimeter which varies in distance from the pivot interposed between said trigger and said member for transmitting movement of said trigger to said member, and means to impositively rotate said cam each operation of the trigger whereby the length of the trigger stroke is varied on successive operations of the trigger.

3. Trigger mechanism for firearms comprising, a trigger, firing mechanism release means, a member to operate said firing mechanism release means, a pivoted cam of irregular outline having its periphery at varying distances from the pivot interposed between said trigger and said member for transmitting movement of said trigger to said member, and frictional means to impositively rotate said cam on each operation of the trigger, whereby the cam is rotated in indeterminate amounts and the length of the trigger stroke is varied on successive operations of the trigger.

4. Trigger mechanism for firearms comprising, a trigger, firing mechanism release means, a member to operate said firing mechanism release means, a pivoted cam of irregular outline having its periphery at varying distances from the pivot interposed between said trigger and said member for transmitting movement of said trigger to said member, and means to bias said trigger toward inoperative position, said means being in frictiona] engagement with the periphery of said cam to impositively rotate said cam in indeterminate amounts during each trigger stroke whereby the length of th trigger stroke is varied on successive operations of the trigger.

5. Trigger mechanism for firearms comprising, a trigger, firing mechanism release means, a member to operate said firing mechanism release means, a pivoted cam of irregular outline having its periphery at varying distances from the pivot interposed between said trigger and said member and in contact with said trigger for transmitting movement of said trigger to said member, means to bias said trigger toward inoperative position, said means being in frictional engagement with the periphery of said cam whereby the cam will be impositively rotated in indeterminate amounts during each stroke of the trigger, and means to hold the member in operative position during the return stroke of the trigger whereby the trigger will be removed from engagement with the cam to permit the cam to rotate freely.

6. Trigger mechanism for firearms comprising, a trigger, firing mechanism release means, a member to operate said firing mechanism release means, a second member pivoted to said firstmentioned member, yieldable means interconnecting said members to cause said members to operate in unison, a cam carried by said second member in contact with said trigger for transmitting movement of said trigger to said second member.

'7. An attachment for firearms having a trigger comprising, a trigger actuating member adapted to contact said trigger, an auxiliary trigger, and pivoted means having its perimeter at varying distances from the pivot interposed between said auxiliary trigger and said trigger actuating member for transmitting movement of said auxiliary trigger to said trigger actuating member, said means being shiftable whereby the length of stroke of the auxiliary trigger is varied on successive operations of the auxiliary trigger.

8. An attachment for firearms having a trigger comprising, a trigger actuating member adapted to contact said trigger, an auxiliary trigger, a pivoted cam of irregular outline having its perimeter at varyingdistances from the pivot carried by saidtrigger actuating member for transmitting movement of said auxiliary trigger to said trigger actuating member, and means to impositively rotate said cam whereby the length of stroke of the auxiliary trigger is varied on successive operations of the auxiliary trigger.

9. Trigger mechanism for firearms comprising, a trigger, firing'mechanism release means, an actuating member for said firing mechanism release means operable by said trigger, said actuating member comprising relatively movable sections, means to unite the sections for unitary movement when the firearm is to be fired, and means to release said uniting means after the firearm has been discharged to permit independent movement of-the said sections.

10. Trigger mechanism forfirearms comprising, a trigger, firing mechanism release means, an actuating member for said firing mechanism release means, a cam interposed between said trigger and said actuating member to transmit movement of said trigger to said actuating member, said actuating member comprising relatively movable sections, latch means to unite the sections for unitary movement when the firearm is to be fired, and means to release said latch after the firearm has been discharged to permit independent movement of the said sections.

11. Trigger mechanism for firearms comprising, a trigger, firing mechanism release means, an actuating member for said firing mechanism release means, a, cam interposed between said trigger and actuating member to transmit movement of said trigger to said actuating member, means to rotate said cam, said actuating member comprising relatively movable sections, latch means to unite the sections for unitary movement when the firearm is to be fired, and means to release said latch after the firearm has been discharged to permit independent movement of the said sections.

12. In trigger mechanism for firearms as claimed in claim 5, means carried by said trigger to release said member holding means as the trigger approaches its position of rest.

13. Trigger mechanism for firearms comprising, a trigger, firing mechanism release means, a member to operate said firing mechanism release means, a pivoted cam of irregular outline interposed between said trigger and said member for transmitting movement of said trigger to said member, means to bias said trigger toward inoperative position, a link interposed between said trigger and said biasing means frictionally contacting said cam and urged toward said cam by said biasing means for impositively rotating the cam in indeterminate amounts during each stroke of the trigger.

14. In trigger mechanism for firearms as claimed in claim 6, remote control means comprising, a rod rotatably connected to said firearm, and a cam carried by said rod to engage said first-mentioned member to prevent its movement when the cam carried by the rod is in one position and to release the member when the rod is rotated.

PAUL PALE.