Firearm hammer spring removal and installation kit

Abstract

The present invention is related to hammer and hammer spring assembly from firearms especially but, not limited to, Stoner Automatic Rifle (SAR) variants, other firearms and other non-firearm mechanisms. The system and method is intended to relieve the hammer spring pressure during removal and installation the hammer. This is accomplished by capturing the hammer and spring legs onto a retainer which holds the spring legs in a position that does not engage any of the nearby features and allows the hammer, spring and retainer to float freely as one assembly on the hammer rotating pin. The system may utilize different shape retainers for other spring shapes and the spring spoon may have other cavity shapes to facilitate manipulating spring legs that are formed to engage on or over pins or other features for use in other firearms or non-firearm assemblies.

Claims

1. A firearm hammer spring removal and installation kit comprising: a spring spoon, a spring retainer, said spring retainer comprising: a channel having a left and right substantially acute triangular blades substantially parallel to each other; the unitary region between said blades being a substantially rectangular backbone; said blades oriented similarly on said backbone; said blades defining an inner area between them; the region of the spring retainer where said blades join said backbone being substantially similar to side A of a right triangle; The region of the spring retainer proximal to side B of the triangle being the lower portion of the spring retainer; the region opposite the lower portion being the upper portion; the region of said blades opposite said backbone defining a spring hook; said spring hooks being distal from said backbone and being substantially rectilinear tabs extending downward from side B; said spring hooks forming an open top channel extending outward from said blades; said lower region of said blades proximal to said backbone defining a semicircular spring saddle; said blades region between said backbone and said spring hooks defining a first and second plane, said first plane proximal to said backbone of said left blade being substantially parallel to the similar plane of said right blade, said second planes being distal to said backbone being converging toward said inner area, said spring hooks being substantially within said first plane; said spring spoon comprising: a shaft having a length, thickness, width and opposite ends; a first end defining a conical spring control cavity whose axis is substantially ninety degrees to the said length and its opening diameter is substantially equal to said thickness, and further defining a cylinder apex, both center lines being axial whose entry is the apex of said conical cavity, together their total depth being less than said width, and first said end further defining a radius radiating from the center of said control cavity substantially equal to one half said thickness defining a keen edge proximal to said conical spring control cavity.

2. A method to remove and install a firearm hammer and spring consisting of the kit described in claim 1 and a firearm: said firearm's receiver defining a firing mechanism cavity having opposing walls, said walls at least defining two opposing hammer pivot pin apertures; said firearm at least including a firing hammer, hammer spring and hammer pivot pin; said hammer having a hammer face end, a length, a thickness and two sides; said hammer defining a hammer pivot pin aperture on an opposite end; said pivot pin apertures adaptive to slideably receive said pivot pin; said hammer having spring mount bosses on each side coaxial to said hammer pivot pin aperture on said opposite end; said hammer spring being double torsion spring with its region between the coils looped around the back of said hammer opposite its face, its coils mounted over said spring mount bosses on each side of said hammer; said spring having legs which extend from said coils; said spring legs having tips opposite said coils; said firing mechanism cavity also having a feature which said legs exert torsion pressure against; said hammer mounted in said firing mechanism cavity between said walls and said pivot pin passed through said pivot pin apertures of said walls and said hammer; said method of use comprising: confirm all ammunition is cleared from said firearm and especially its ammunition chamber; removing any features blocking access to said firing mechanism cavity; positioning said spring retainer on said hammer and spring by passing said blades on each side of said hammer until said backbone rests on said hammer face and said spring saddle rests on said spring coils; pivotably urging said spring hooks toward said spring leg tips; said spring spoon is manipulated into said firing mechanism cavity with said spring control cavity facing said hammer spring leg tip, the spoon being advanced on said hammer spring leg as said keen edge is used to urge the spring tip into said apex cylinder; while continuing to exert force on the spoon toward said hammer spring coil the spring leg is lifted and engaged into said spring hook; the process is repeated on the second spring leg; said pivot pin is pushed out of said apertures sans hammer spring pressure; said hammer with spring can be removed from said firing mechanism cavity; said spring legs removed from said hooks; said spring retainer may be disengaged from said hammer and spring; and the method is reversed for installation of said hammer and hammer spring except confirming clearing all ammunition should be performed first.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1. Shows an oblique view of the right hand side of an AR15 lower receiver with the hammer protruding above the lower reciever.

(2) FIG. 2. Shows an oblique view of the right hand side of an AR15 lower receiver with the hammer and hammer spring assembly removed and above the lower reciever.

(3) FIG. 3. Shows a front view of a hammer spring.

(4) FIG. 4. Shows a side view of a hammer spring.

(5) FIG. 5. Shows a flat pattern view of the hamAR cage spring retainer sheet metal blank.

(6) FIG. 6. Shows the spring spoon.

(7) FIG. 7. Shows a side view of a formed hamAR cage.

(8) FIG. 8. Shows a front view of a formed hamAR cage.

(9) FIG. 9. Shows a front view of the spring spoon including the spring control cavity.

(10) FIG. 10. Shows a cutaway view of the conical spring control cavity.

(11) FIG. 11. Shows the hamAR cage being positioned around an installed hammer.

(12) FIG. 12. Shows the hamAR cage positioned on the hammer/hammer spring assembly with the spring saddle engaged on the spring coils.

(13) FIG. 13. Shows the hamAR cage positioned on the hammer/hammer spring assembly as the group has been rotated on the hammer pin toward the back of the trigger housing.

(14) FIG. 14. Shows a cutaway of the spring spoon spring control cavity with the apex cylinder engaged on the spring leg.

(15) FIG. 15. Shows the spring legs having been secured in the spring hooks of the hamAR cage and the group is free to rotate some degrees of rotation on the hammer pin and all hammer spring force is eliminated from acting on the hammer pin.

(16) FIG. 16. Shows a top view of the hamAR cage engaged on the hammer assembly and rotated as shown in FIG. 13 and the spring spoon positioned to be engaged on the hammer spring leg.

DETAIL DESCRIPTION OF THE DRAWINGS

(17) FIG. 1. Shows an oblique view of the right hand side of an AR15 lower receiver 1 and the forward web 2 of the trigger housing with the hammer 3 protruding above the lower receiver.

(18) FIG. 2. Shows an oblique view of the right hand side of an AR15 lower receiver 1 with the hammer and hammer spring assembly 3, 4 removed and above the lower receiver.

(19) FIG. 3. Shows a front view of a hammer spring 4.

(20) FIG. 4. Shows a side view of a hammer spring 4.

(21) FIG. 5. Shows a flat pattern view of the hamAR cage 6 spring retainer sheet metal blank.

(22) FIG. 6. Shows the spring spoon 7.

(23) FIG. 7. Shows a side view of a formed hamAR cage 6, leg 8, spring saddle 9, hook 10 and back bone 14.

(24) FIG. 8. Shows a front view of a formed hamAR cage 6 leg 8, hook 10 and back bone 14.

(25) FIG. 9. Shows a front view of the spring spoon 7, spring control cavity 11, keen edge 12 and cylinder apex 13.

(26) FIG. 10. Shows a cutaway view of spring spoon 7, spring control cavity 11, keen edge 12 and cylinder apex 13.

(27) FIG. 11. Shows the hamAR cage 6 being positioned around an installed hammer/hammer spring assembly 3, 4 with a leg 8 on each side of the hammer 3 as back bone 14 is moved toward the face of hammer 3 as the hammer is still urged against forward web 2 of the trigger housing.

(28) FIG. 12. Shows the hamAR cage 6 positioned on the hammer/hammer spring assembly 3, 4 with back bone 14 engaged on the face of hammer 3 and the spring saddles 9 engaged on the spring coils.

(29) FIG. 13. Shows the hamAR cage 6 positioned on the hammer/hammer spring assembly 3,4 as the group has been rotated on the hammer pin 5 toward the back of the trigger housing.

(30) FIG. 14. Shows a cutaway of the spring spoon spring 7 control cavity 11 with the apex cylinder 13 engaged on the spring leg.

(31) FIG. 15. Shows the spring legs having been secured in the spring hooks 10 of the hamAR cage 6 and the group is free to rotate some degrees of rotation on the hammer pin 5 and all hammer spring force is eliminated from acting on the hammer pin.

(32) FIG. 16. Shows a top view of the hamAR cage 6 engaged on the hammer and spring assembly 3,4 and rotated on hammer pin 5 as shown in FIG. 13 and the spring spoon 7 positioned to be engaged on the hammer spring leg.