TWO-PIECE HAMMER FOR A FIREARM

Description

FIELD OF THE INVENTION

The present invention relates to firearms, and more particularly, to a hammer for use within a firearm, and still more particularly, to a two-piece hammer adapted to be used within a firearm firing mechanism, such as that of the M1911 pistol.

BACKGROUND OF THE INVENTION

There are a number of automatic and semi-automatic pistols used by military personnel, as well as by law enforcement and civilians. Due to its early adoption by the United States military, and its prolonged service life within the armed forces spanning nearly a century, arguably the most popular pistol in use, particularly within the United States, is the M1911 pistol (and its later updated version designated M1911A1) and its clones, generally “the M1911 pistol.” The M1911 pistol is a recoil-operated semi-automatic pistol firing from a closed breech. The pistol is magazine-fed and is typically chambered for the .45 Automatic Colt Pistol (ACP) cartridge wherein each magazine generally holds 7 to 8 rounds (bullets). While typically configured to fire .45 caliber rounds, dedicated versions of the M1911 pistol may be modified to fire 9 mm rounds.

In operation, a full magazine is inserted in the stock portion of the pistol's frame. Being a single-action with multiple safeties built in, the M1911 pistol is designed to be worn “cocked and locked”—that is, the hammer is pulled back in the cocked position and the manual safety is engaged to prevent firing of the pistol. With a round in the chamber, a shooter squeezes the grip and disengages the manual safety whereby pulling (squeezing) of the trigger which disengages the sear from the hammer. The hammer is then pivoted forward due to force applied via the main spring. The hammer then propels the firing pin forward whereby the firing pin ignites the cartridge primer which causes the powder inside the cartridge to ignite.

The burning powder evolves high pressure gases which propels the bullet down the barrel and ultimately out the muzzle. The expanding gases simultaneously push the cartridge case and the locked slide and barrel rearward. As the bullet exits the muzzle of the barrel, the pressure inside the barrel is diminished. Also at about this time, the barrel has completed its rearward travel and, due to the action of the barrel link, is pulled downward such that the barrel disengages from the slide. The slide, however, continues to travel rearward pulling the spent cartridge case with it. The cartridge case then strikes the ejector whereby the cartridge case is ejected from the chamber. As the slide continues its rearward movement, it re-cocks the hammer thereby preparing the pistol for the next firing sequence.

To prevent the pistol from operating as a fully automatic pistol, the disconnector is also pushed down by the slide such that the disconnector prevents the hammer from coming forward again as the slide starts its forward movement under the force of the recoil spring. As the slide returns forward, it strips a new round from the magazine and pushes the round into the barrel's chamber. After the cartridge is fully inserted in the chamber, the slide reengages the barrel and pushes the barrel forward. Due to the barrel link, the barrel moves upwards until the barrel's slots engage the slide and lock the barrel and slide together. At this point, the pistol is ready to be fired again.

Many pistols, including the M1911 pistol, allow customization of various components of the firearm. One particularly popular customization is swapping of the pistol grip plates, whether for improved grip, aesthetics, or both. Another popular customization is swapping of the hammer for a different hammer design or configuration. However, while exchanging pistol grips simply requires unscrewing and reattaching the plate mounting screws, swapping of the hammer requires one to disassemble the entire pistol grip to extract the hammer from the firing mechanism. The various springs and other internal components must also be carefully accounted for while swapping in the new hammer. Due to this complexity, hammer swaps are typically conducted by trained professionals. Thus, while pistol owners are free to periodically change the appearance of their firearms by changing the grip plates, customization of the hammer is usually limited to selecting the desired hammer at time of purchase.

As such, there is a need for a customizable hammer for a firearm which does not require disassembly of the firearm grip to interchangeably swap the hammer, such as for improved grip, aesthetics, or both. The present invention addresses these, as well as other needs.

BRIEF SUMMARY OF THE INVENTION

In general, one aspect of the present invention is directed to a hammer for use within a firing mechanism of a firearm wherein the firing mechanism includes the hammer, a sear, sear spring, and a hammer strut. The hammer comprises a thumb portion removably coupled to a sear portion. The thumb portion includes a spur end configured to be engaged by a thumb of a user to cock the hammer to a firing position, and a sear end having a sear mating end wall defining a non-planar surface. The sear portion includes a triggering end configured to engage the sear and a thumb end having a thumb mating end wall defining a corresponding non-planar surface which is adapted to mate with the sear mating end wall of the thumb portion. The thumb portion is configured to be removable from the sear portion without requiring decoupling of the sear portion from the remainder of the firing mechanism. The spur end may further include one or both of a left extended wide spur portion and a right extended wide spur portion, and the thumb portion may be adapted to receive and display one or more ornamental features.

In a further aspect of the present invention, the thumb portion may include a first sidewall and an opposing second sidewall wherein the sear mating end wall extends between the first and second sidewalls. The sear mating end wall comprises a first end segment extending inwardly from the first sidewall toward the second sidewall; a second end segment extending inwardly from the second sidewall toward the first sidewall; and third, fourth and fifth contiguous wall segments extending from the first end segment to the second end segment. The third wall segment forms a concave nodule extending inwardly from the first end segment, the fourth wall segment forms a convex recess, and the fifth wall segment forms a linear portion between the fourth wall segment and the second end segment.

The sear portion may include a first sidewall and an opposing second sidewall wherein the thumb mating end wall extends between the first and second sidewalls. The thumb mating end wall comprises a first end segment extending inwardly from the first sidewall toward the second sidewall; a second end segment extending inwardly from the second sidewall toward the first sidewall; and third, fourth and fifth contiguous wall segments extending from the first end segment to the second end segment. The third wall segment forms a convex recess dimensioned to receive the concave nodule formed by the third wall segment of the sear mating end wall, the fourth wall segment forms a concave nodule dimensioned to be received within the convex recess formed by the fourth wall segment of the sear mating end wall, and the fifth wall segment forms a linear portion between the fourth wall segment and the second end segment.

Accordingly, the sear mating end wall and the thumb mating end wall may interlockingly engage one another, and the sear end may include a throughbore and the thumb end may include a threaded bore. The throughbore and the threaded bore are configured to be aligned so as to receive a threaded fastener therein to secure the thumb portion to the sear portion.

Additional objects, advantages and novel features of the present invention will be set forth in part in the description which follows, and will in part become apparent to those in the practice of the invention, when considered with the attached figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings form a part of this specification and are to be read in conjunction therewith, wherein like reference numerals are employed to indicate like parts in the various views, and wherein:

FIG. 1 is a side view of a representative firearm, such as an M1911 pistol, suitable for incorporating an embodiment of an interchangeable hammer in accordance with present invention;

FIG. 2 is an exploded view of the representative M1911 pistol shown in FIG. 1;

FIG. 3 is a perspective view of an exemplary embodiment of an interchangeable hammer in accordance with present invention;

FIG. 4 is a cross sectional view of the exemplary interchangeable hammer taken generally along line 4-4 in FIG. 3;

FIG. 5 is a bottom side perspective exploded view of the exemplary interchangeable hammer shown in FIG. 3;

FIG. 6 is a top side perspective exploded view of the exemplary interchangeable hammer shown in FIG. 3;

FIG. 7A shows an exemplary alternative thumb portion of an interchangeable hammer in accordance with the present invention;

FIG. 7B shows another exemplary alternative thumb portion of an interchangeable hammer in accordance with the present invention; and

FIG. 7C shows still another exemplary alternative thumb portion of an interchangeable hammer in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings in detail, and specifically to FIGS. 1 and 2, an exemplary firearm, such as the M1911 pistol, is generally indicated by reference numeral 10. Pistol 10 consists of a number of components and subcomponents. Major components of pistol 10 include barrel 12, slide 14, frame (also referred to as a receiver) 16 and magazine 18. Barrel 12 may be any desired length, such as the standard 5 inch length, but may be also be shorter, such as 4.5 inches, 4 inches or even 3 inches. Frame 16 is generally comprised of a stock portion 20, a barrel receiving portion 22 and trigger guard 24. When pistol 10 is assembled, magazine 18 (filled with one or more rounds or bullets) is inserted in the stock portion of frame 16. A single round is then fed into chamber 26 of barrel 12. Barrel 12 is coupled to slide 14 via barrel bushing 28. When slide 14 is in its forward position, such as that shown in FIG. 1, barrel slots 30 on barrel 12 mate with and engage corresponding tabs within slide 14 (not shown) so as to lock the barrel with the slide.

To fire the pistol, a shooter pulls (squeezes) trigger 32 causing sear 34 to rotate about sear pivot pin 35 to disengage from hammer 36. Hammer 36 then pivots forward about hammer pin 37 due to a force applied via hammer strut 31 and main spring assembly 39 residing within main spring housing 38. Main spring housing 38 is secured to stock portion 20 via a main spring housing pin 41. Hammer 36 then propels firing pin 40 forward against the force of firing pin spring 43 whereby the firing pin ignites the cartridge primer which causes the powder inside the cartridge to ignite. The burning powder evolves high pressure gases which propels the bullet down barrel 12 and ultimately out muzzle 42, as generally indicated by arrow 44. The expanding gases simultaneously push the cartridge case and the locked slide and barrel rearwardly (i.e., opposite muzzle 42 of barrel 12) as generally indicated by arrow 46 whereby the spent cartridge case is removed from chamber 26 via extractor 53. As the bullet exits the muzzle of the barrel, the pressure inside the barrel is diminished. Rearward travel of barrel 12 is limited due to barrel link 48 which pivots to cause barrel 12 to slide downwardly and disengage from slide 14. Slide 14 continues its rearward movement such that the spent cartridge is ejected out breech 50 via ejector 55. As the slide continues its rearward movement, it recocks hammer 36 thereby preparing the pistol for the next firing sequence.

To prevent pistol 10 from operating as a fully automatic pistol, disconnector 52 is pushed downward by the rearward travel of slider 14. Together, sear 34, hammer 36 and disconnector 52 may be referred to as a fire control group. In this manner, disconnector 52 prevents hammer 36 from coming forward again as slide 14 starts its forward movement under the force of compressed recoil spring assembly 54. As slide 14 returns to its forward position (FIG. 1), it strips a new round (bullet) from magazine 18 and pushes the round into chamber 26 of barrel 12. After the cartridge is fully inserted in chamber 26, slide 14 reengages barrel 12 thereby pushing barrel 12 forward. Under action of barrel link 48, barrel 12 moves upwards until barrel slots 30 engage with their respective tabs within slide 14, thereby locking barrel 12 and slide 14 together. At this point, pistol 10 is ready to be fired again.

After firing the last round in magazine 18, or through manual actuation, slide stop 47 locks slide 14 in its rearward position. Slide stop 47 is pivotally actuated about slide stop pin 49 by the follower (not shown) within the emptied magazine impacting slide stop post 51 such that slide stop pin 49 and slide stop post 51 operate to secure slide 14 to frame 16. Barrel link 48 is also pivotally mounted to slide stop pin 49 so as to enable the rearward and downward movement of the barrel as the slide moves rearwardly immediately after firing a round.

The M1911 pistol, such as that shown in FIGS. 1 and 2, includes numerous safety features to prevent unwanted discharge of the pistol. Safety lock 56 (also known as a thumb safety) may be pivoted upwardly via safety pin 58 such that movement of sear 34 is prevented. Safety lock 56 may be located on either or both of the left side or right side of the stock to accommodate the preferred handedness of the shooter. Pistol 10 may also include grip safety 60 having a grip safety arm 62. When pistol 10 is in its resting state, grip safety arm 62 contacts trigger 32 and prevents movement of trigger 32 until grip safety 60 is depressed by the web of the shooter's hand as he or she grasps the pistol stock portion 20. Once the pistol is grasped, grip safety 60 pivots about safety pin 58 thereby disengaging grip safety arm 62 from trigger 32 such that trigger 32 can then be pulled to initiate firing of the pistol as discussed above.

To maintain the above safety features in their proper resting positions, pistol 10 may include a sear spring 64. Sear spring 64 is housed within the stock portion 20 of pistol 10 and is held in place via main spring housing 38. Sear spring 64 is typically a three-prong flat spring wherein one prong of the spring pushes trigger 32 forward (i.e. in the direction of arrow 44), a second prong pushes sear 34 so as to maintain sear 34 contact with hammer 36, and a third prong which pushes grip safety 60 backward (i.e. in the direction of arrow 46) so as to keep grip safety arm 62 in contact with trigger 32 when the pistol is not gripped by the shooter.

Covering each side of stock portion 20 is a respective stock member 66 (for simplicity, only one stock member is shown in FIG. 2). Stock member 66 (also commonly referred to as a grip) is customizable so that each shooter can create a pistol grip which provides the desired aesthetics and degrees of comfort and gripability. Stock member 66 is secured to stock portion 20 via stock member screws 68 threaded into a stock bushing 70.

Turning now to FIGS. 3 through 6, an exemplary embodiment of a hammer 100 that may be adapted for use within a firearm, such as but not limited to pistol 10 shown in FIGS. 1 and 2, may be a comprised of a two-component subassembly including a thumb portion 110 and sear portion 112. Thumb portion 110 generally includes a spur end 114 and a sear end 116 while sear portion 112 generally includes a thumb end 118 and a triggering end 120. Sear end 116 includes a sear mating end wall 122 while thumb end 118 includes a thumb mating end wall 124 whereby the respective end walls 122, 124 define corresponding non-planar surfaces such that thumb portion 110 and sear portion 112 matingly couple to one another to form a continuous web defining the body of the hammer 100.

In one aspect of the invention, respective end walls 122, 124 interlockingly engage one another to prevent unwanted or inadvertent displacement of thumb portion 110 and/or sear portion 112. To further secure the two portions 110, 112 together, sear end 116 of thumb portion 110 may include a throughbore 126 while thumb end 118 of sear portion 112 may include a threaded bore 128. Throughbore 126 and bore 128 are configured to align with one another when portions 110, 112 are properly seated against one another whereby a threaded fastener, such as but not limited to a set screw or bolt 130 may threadably engage bore 128 to secure thumb portion 110 to sear portion 112.

As shown in FIGS. 5 and 6, thumb portion 110 includes a first sidewall 132 and a second sidewall 134, with the tortuous sear mating end wall 122 extending therebetween. In an exemplary embodiment, sear mating end wall 122 may include a first end segment 136 extending inwardly from first sidewall 132 toward second sidewall 134. Second end segment 138 extends inwardly from second sidewall 134 toward first sidewall 132. Third, fourth and fifth contiguous wall segments 140, 142, 144 extend between first end segment 136 and second end segment 138. Third wall segment 140 extends inwardly from first end segment 136 and forms a concave nodule 146 followed by fourth wall segment 142 which defines a convex recess 148 within sear mating end wall 122. Fifth wall segment 144 extends between fourth wall segment 142 and second end segment 138 and forms a generally planar surface 150.

As further shown in FIGS. 5 and 6, sear portion 112 includes a first sidewall 152 and an opposing second sidewall 154, with the thumb mating end wall 124 extending therebetween. In continuing the above exemplary embodiment, thumb mating end wall 124 may include a first end segment 156 extending inwardly from first sidewall 152 toward second sidewall 154. Second end segment 158 extends inwardly from second sidewall 154 toward first sidewall 152. Third, fourth and fifth contiguous wall segments 160, 162, 164 extend between first end segment 156 and second end segment 158. Third wall segment 160 extends inwardly from first end segment 156 and forms a convex recess 166 dimensioned to receive concave nodule 146 formed by third wall segment 140 of sear mating end wall 122. Fourth wall segment 162 forms a concave nodule 168 dimensioned to be received within convex recess 148 formed by fourth wall segment 142 the sear mating end wall 122. Fifth wall segment 164 may then form a linear portion 170 defining a generally planar surface between fourth wall segment 162 and second end segment 158.

In one aspect of the present invention, thumb portion 110 is configured to be removable from sear portion 112 without requiring decoupling of sear portion 112 from the remainder of the firing mechanism. That is, sear portion 112 may include right and left leg portions 180, 182 defining a channel 184 therebetween. Channel 184 may be dimensioned to receive a hammer strut (e.g., hammer strut 31, FIG. 1) therein, wherein the hammer strut is pivotally secured via a hammer strut pin (e.g., hammer strut pin 31a, FIG. 1) within hammer strut pin holes 186a, 186b defined within leg portions 180, 182, respectively. Right leg portion 180 and left leg portion 182 may also define respective hammer pin holes 188a, 188b therein for receiving a hammer pin (e.g., hammer pin 37, FIG. 1) to pivotally mount sear portion 112 to the pistol frame (e.g., pistol frame 16, FIG. 1).

In an exemplary embodiment, hammer 100 may be secured to the pistol frame (e.g., frame 16) solely via sear portion 112. Accordingly, thumb portion 110 may be swapped/replaced/adjusted as needed or desired via set screw or bolt 130 without requiring manipulation of the hammer strut, sear spring, main spring, and all associated elements of the firing mechanism. As a result, the general owner/user of the firearm (e.g., pistol 10) is free to customize the hammer (e.g., thumb portion 110) without requiring special tools or know-how.

Turning now to FIGS. 7A-7C, exemplary alternative thumb portions 110a, 110b, 110c may be interchangeably mounted to sear portion 112 as described above. As shown in FIGS. 3-6, thumb portion 110 may include spur end 114 having a first width W. However, should the user desire a wider spur end for ease in cocking hammer 100, thumb portion 110 may be replaced by thumb portion 110a which has a wider spur end 114a having a width W_A formed by extended wide spur portions E_L and E_R while sear end 116a and throughbore 126a retain the same configuration as sear end 116 and throughbore 126.

Alternatively, depending upon the handedness of the user, thumb portion 110 may be swapped with a right-handed spur extension thumb portion 110b or left-handed spur extension thumb portion 110c. Similar to thumb portion 110a having wide spur end 114a, right-handed spur extension thumb portion 110b may have a width W₃ and include a right extended wide spur portion E_R while sear end 116b and throughbore 126b retain the same configuration, while left-handed spur extension thumb portion 110c may have a width W₄ and include a left extended wide spur portion E_L while sear end 116c and throughbore 126c retain the same configuration. It should be noted that W₃ may be the same as or different than W₄.

It should be noted that while other mating surface profiles between sear mating end wall 122 and thumb mating end wall 124 may be envisioned, fourth portions 144, 164 are linear to promote receipt of and proper threadability of throughbore 126 and bore 128 between various interchangeable thumb and sear portions. It should be further noted that the interaction between nodules 146 and 168, along with linear portions 144, 164 promote cocking of hammer 100 (such as along arrow 190) with no play or wobble at the junction of the thumb and sear portions 110, 112. The interaction between nodules 146 and 168 also provides for efficient transfer of force F through hammer 100 when the surface of first sidewall 132 strikes the firing pin upon pulling of the trigger without imparting shear forces at the junction of the thumb and sear portions 110, 112.

In a further aspect of the present invention, thumb portion 110 and sear portion 112 may each be fabricated through current extrusion manufacturing techniques and processes leading to reduced costs of manufacture and increased production yields. It should be further noted that while shown and described with regard to a M1911 pistol, any suitable firearm may be adapted or modified to include a hammer in accordance with the present invention.

Although the present invention has been described in considerable detail with reference to certain aspects thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the aspects contained herein.

All features disclosed in the specification, including the claims, abstract, and drawings, and all the steps in any method or process disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. Each feature disclosed in the specification, including the claims, abstract, and drawings, can be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.