Anti-opening bolt assembly system using the hammer

Abstract

The invention relates to an anti-opening bolt assembly system utilizing the hammer springs, achieved by sliding the hammer spring rod end from a first end A to a second end B within a built-in opening of the hammer. This mechanism facilitates the forward movement of the bolt assembly, ensuring its closure following the firearm firing. The system leverages components of the percussion system without additional parts, preserving the simplicity, compactness, and reduced weight of the firearm. While no risk arises from the partial or full opening of the bolt assembly after firing, it is preferred to keep the bolt assembly closed after firing. During firing, the movement of the hammer spring guide rod end from the first end to the second end of the opening enables the hammer to apply forces to the bolt assembly, utilizing the decompression forces of the hammer springs.

Description

Anti-opening bolt assembly system using the hammerField of the invention

[0001] The present invention relates to the field of firearms and, more particularly, to anti-opening bolt assembly systems using the percussion system, particularly the rotating hammer, to keep the bolt assembly in a closed position subsequent to firing.Background of the invention

[0002] Certain firearms, mainly manually operated repeating firearms such as straight pull rifles, pump-action rifles, pump-action shotguns, etc... may experience partial opening or sometimes unlocking after firing. While this poses no safety risk since unlocking occurs after the projectile has left the barrel, it is considered undesirable.

[0003] Some of the existing firearms incorporate dedicated anti-opening breech lever systems supported by percussion systems; however, these systems are characterized by complexity, bulkiness, and numerous additional components. Certain semi-automatic firearms utilize a sliding hammer spring guide, primarily to compromise the starting trigger pull force and percussion energy rather than serve as an anti-opening mechanism for the breech.

[0004] Document US 2010 / 236120 discloses a fire control assembly for a firearm including a trigger engagement link comprising a forward end, a rearward end, and an intermediate portion. The fire control assembly further includes a sear including a bottom portion engageable with the intermediate portion of the trigger engagement link, and a hammer moveable between cocked and firing positions. The hammer includes a link displacement portion operable to displace the forward end of the trigger engagement link as the hammer is moved from its firing position to its cocked position. The displacement of the forward end of the trigger engagement link by the link displacement portion of the hammer disengages the intermediate portion of the trigger engagement link from the bottom portion of the sear so as to at least temporarily deactivate the fire control assembly.

[0005] It is desirable to have firearms equipped with a straightforward integrated anti-opening breech or bolt assembly system. Such a system could utilize components like hammer springs and / or the hammer itself to harness their forces, thereby maintaining the breech or bolt assembly securely in the closed position.Summary of the invention

[0006] The present invention aims to provide a firearm featuring an antiopening bolt assembly system utilizing the hammer. This system incorporates a hammer spring guide rod end that slides within an opening or recess in the hammer. Its purpose is to secure the bolt assembly in its closed position or guide it forward to this position after firing when partially or fully opened. Notably, no additional components are added to ensure the bolt assembly’s closure after firing; only the existing percussion system, comprising mainly the hammer, hammer springs, and hammer spring guide rod, is utilized. This system allows the hammer not only to disengage from the trigger when pulled to fire the firing pin but also to exert sufficient force to maintain or return the bolt assembly to the closed position post-firing due to the firing inertia. This functionality is achieved by moving the hammer spring guide rod end within the hammer’s opening from the first end to the second end, maintaining the hammer spring under compression.

[0007] The present invention is related to a firearm comprising:- a frame defined with a longitudinal axis;- a bolt assembly movably mounted on the frame and displaceable along the longitudinal axis between a closed position and an open position or vice versa; - a trigger pin and a trigger pivotally mounted upon the frame by said trigger pin; - a hammer pin and a hammer pivotally mounted upon the frame by said hammer pin, the hammer being able to adopt a position ready for fire and a subsequent fired position, said hammer comprising an elongated opening or recess with a first end and a second end;- a hammer spring guide rod provided at one end with a hammer spring guide rod end,- at least one hammer spring mounted on said hammer spring guide rod, with said at least one hammer spring configured to induce movement of the hammer between the position ready for fire and the fired position,characterized in that said hammer spring guide rod end is movably mounted within the elongated opening or recess, with a movement from the first end to the second end of the elongated opening or recess when the hammer is in the fired position, allowing the at least one hammer spring to push the bolt assembly forward to the closed position via the hammer.

[0008] Preferably, the at least one hammer spring is configured to exert a force at a point of application located at the first end A when the hammer is engaged with the trigger.

[0009] Preferably, the point of application of the force of the at least one hammer spring is capable of moving relative to the hammer from the first end A to the second end B after firing.

[0010] Preferably, the force exerted by the hammer on the bolt assembly when the hammer spring guide rod end is positioned at the second end B is capable of pushing forward the said bolt assembly to the close position when partially recoiled during or after firing. This takes the advantage from the additional leverage provided by the position B compared to the position A.

[0011] Preferably, the bolt assembly comprises a transverse pin.

[0012] Preferably, the hammer is capable of contacting the transverse pin when the said hammer pushes forward the bolt assembly to the closed position after firing.

[0013] Preferably, the at least one hammer spring is capable of at least partially compressing when the hammer is engaged with the trigger.

[0014] Preferably, the at least one hammer spring is capable of at least partially decompressing when the hammer is decocked, thereby pushing the hammer toward the bolt assembly.

[0015] Preferably, the hammer maintains contact with the transverse pin exerting forces on the bolt assembly after firing to keep the said bolt assembly in the closed position.

[0016] Preferably, the firearm comprises a handcocking arm and a handcocking arm pin with said handcocking arm pivotally mounted on the frame via the handcocking arm pin.

[0017] Preferably, the hammer and the handcocking arm are interconnected by the hammer spring guide rod.

[0018] Preferably, the at least one hammer spring is mounted on the hammer spring guide rod and confined between the hammer and the handcocking arm.

[0019] Preferably, the at least one hammer spring is mounted on the hammer spring guide rod and confined between the hammer and a fixed point of the firearm.

[0020] Preferably, the at least one hammer spring is at least partially compressed when engaged with the trigger.

[0021] Preferably, the at least one hammer spring is partially decompressed after firing.

[0022] Preferably, the hammer spring guide rod end engages with the opening to move from the first end A to the second end B when the hammer is disengaged from the trigger.Brief description of the drawings

[0023] Figure 1 is a cross-sectional view of the firearm and a zoom-in of the percussion system before firing in the position ready for fire.

[0024] Figure 2 is a 3D view representing the percussion mechanism.

[0025] Figure 3 is a cross-sectional view of the firearm and a zoom-in of the anti-opening bolt assembly system after firing in the fired position.Detailed description of the invention

[0026] The present invention will be described in greater detail in one or more preferred embodiments of the invention with reference to the appended figures and for which elements or details can be combined. The same principleapplies when combining elements from the figures that illustrate the principal component of the current invention.

[0027] The expression “opening” or “recess” may refer to various forms such as a hole, aperture, orifice, slot, drill, tunnel, groove, or any similar structure designed for material removal that facilitates the engagement of another mechanical component, enabling specific movements. In more detail, the “opening” is defined with a first end and a second end, designed to accommodate sliding or liner movements of an engaged component such as the hammer spring guide rod rather than solely pivoting or rotational motions.

[0028] In the present invention, the opening is positioned within the body of the hammer, or more precisely, within the lower part of the body of the hammer near its pivot axis and distant from the contact point with the bolt assembly. This positioning ensures that the decompression forces exerted by the hammer springs are effectively utilized to either push forward or maintain the bolt assembly in the closed position.

[0029] Figure 1 illustrates a cross-sectional view of the firearm 50 in the upper-left corner, showcasing the percussion mechanism comprising the hammer, the hammer springs, and the hammer spring guide rod positioned in the firing-ready mode, prepared for striking the firing pin 20. Additionally, Figure 1 includes an enlarged view of this mechanism. The trigger 9 is pivotally mounted on the frame 51 by the trigger pin 13, interacting with the hammer 1 , also pivotally mounted upon the frame 51 by the hammer pin 3. This interaction involves a first hook on the upper side of the trigger 9 engaging a second hook on the hammer 1. Consequently, pulling the trigger 9 disengages the hammer 1, causing it to strike the firing pin 20.

[0030] Figure 1 further depicts the firearm 50 in its charged state, referred to as the firing position or position ready for fire, where the hammer 1 is engaged with the trigger 9 and the hammer springs 5 are at least partially compressed. The hammer springs 5 are respectively mounted on a hammer spring guide rod 4A as shown in Figure 2. This hammer spring guide rod 4A is provided at one end with a hammer spring guide rod end 4. This hammer spring guide rod end 4 forms a transverse extension relative to the axis of the hammer spring guide rod4A. In the example, there is one hammer spring guide rod end 4 connecting both hammer spring guide rods 4A. According to a variant not represented, the firearm can comprise only one hammer spring guide rod. On each hammer spring guide rod, one or several hammer springs can be mounted.

[0031] The hammer 1 comprises a elongated opening 2 extending between a first end A and a second end B, accommodating the hammer spring guide rod end 4. In more detail, in the firing position of the firearm 50, the hammer spring guide rod end 4 resides at the first end A of the opening 2 of the hammer 1, allowing the hammer springs 5 to apply force at this contact point. Users are advised to exercise caution, as pulling the trigger 9 can potentially fire the firearm 50 if loaded.

[0032] In a preferred embodiment, the hammer 1 disclosed herein incorporates a built-in opening 2 designed to accommodate movement or sliding of the hammer spring guide rod end 4 between its first end A and second end B. The opening 2 is preferably configured as a channel. In the example, it is a through opening. In a variant not represented, it can be a non-through opening, also called recess. In this variant, the recess accommodates the hammer spring guide rod end of one hammer spring guide rod.

[0033] Figure 1 further illustrates a handcocking arm 10 linked to the hammer 1 by the hammer spring guide rod 4A, with the hammer springs 5 confined between the hammer 1 and the handcocking arm 10. This configuration may allow the hammer springs 5 to be partially compressed both when the hammer 1 is engaged with the trigger 9, ready to fire the firing pin 20, and when the hammer 1 is disengaged from the trigger 9 after striking the firing pin 20 to discharge the firearm 50.

[0034] The handcoking arm 10 may be abended or replaced by a pin positioned similarly to the hammer spring guide rod support 12 to ensure the intended functionality of the hammer spring guide rod 4 and the hammers springs 5. It should be understood that the present invention may function without the need for the handcocking arm 10. Broadly speaking, the hammer springs 5 are confined between the hammer 1 and a fixed point such as the hammer spring guide rod support 12.

[0035] Upon disengagement of the hammer 1 from the trigger 9 following firing, the hammer springs 5 may experience partial decompression. It is preferred that the hammer springs 5 do not fully decompress after firing, ensuring that forces from the hammer spring guide rod end 4 are consistently applied on the hammer 1 at either the first end A or the second end B of the opening 2.

[0036] Figure 2 provides a comprehensive 3D representation of the percussion mechanism, highlighting its key operational components. The hammer 1 and the trigger 9 are pivotally mounted by the hammer pin 3 and the trigger pin 13, respectively. Thus, when the trigger 9 is pulled while the hammer 1 is engaged, it pivots around the hammer pin 3, potentially striking the firing pin 20.

[0037] It is important to mention that the hammer springs 5 may maintain partial compression both when the hammer 1 is engaged with the trigger 9 and even after the hammer 1 is disengaged from trigger 9 upon firing.

[0038] Figure 2 illustrates the hammer 1 connected to the handcocking arm 10 via two hammer spring guide rods 4, positioned on opposite sides and each equipped with a hammer spring 5. When the first hinge of the trigger 9 engages with the hammer 1, the hammer springs 5 compress, preparing firearm 50 for firing. The trigger 9 pulling initiates the firing sequence, causing the second hook of the hammer 1 to disengage from the first hook of the trigger 9. Utilizing the compression forces from the hammer springs 5, the hammer 1 pivots around the hammer pin 3, delivering sufficient energy to strike the firing pin 20, thereby facilitating successful firing.

[0039] Figure 2 further illustrates the opening 2 within the body of the hammer 1, shaped as either a linear through-hole or a through-channel comprising a first end A and a second end B. The hammer spring guide rod 4A is connected to the hammer 1 through the opening 2, enabling movement along its entire length from one end to the other.

[0040] The hammer springs 5 may be configured to be positioned on the hammer spring guide rod 4, trapped between the hammer 1 and the handcocking arm 10. Specifically, each hammer spring 5 surrounds its respective hammerspring guide rod and is confined between its two ends. When the hammer 1 is engaged with the trigger 9, the hammer springs 5 may undergo partial compression, causing the hammer spring guide rod end 4 within the opening 2 to exert forces at a designated point in the first end A of said opening 2.

[0041] In an alternative embodiment, the opening 2 within the body of the hammer 1 may be replaced by one or more additional mechanical components connected with the hammer 1 designed to accommodate the hammer spring guide rod end 4. This configuration may allow the hammer to pivot either to strike the firing pin 20 or to push forward the bolt assembly 8. However, it is preferred not to add any parts to the percussion mechanism to maintain the firearm 50 as compact and simple as possible, consistent with the invention’s objective and subject matter.

[0042] Figure 3 depicts a cross-sectional view of the anti-opening bolt assembly system post-firing. The hammer 1 is in its fired position, making contact with the firing pin 20. Additionally, the said hammer 1 is contacting the transverse pin 7. The pushing forces exerted by the hammer springs 5 ensure that the hammer 1 remains in contact with the transverse pin 7 while also pushing forward the bolt assembly 8 to its closed position after firing.

[0043] In another embodiment, the transverse pin 7 may be optional and either omitted or substituted by an integrated geometric feature or form within the bolt assembly 8. The bolt assembly 8 may be fabricated either partially or entirely from treated or untreated steel. Furthermore, the section of the bolt assembly 8 that may interface with the hammer 1 may be subjected to hardening or other treatments, or fabricated from different material than the rest of the bolt assembly 8 to withstand impacts from the hammer 1.

[0044] It is worth mentioning that the distance between the hammer 1 and the handcocking arm 10 in the firing position of the firearm 50 may differ after firing. In more detail, the distance between the two ends of the hammer spring guide rod 4, from the hammer spring guide rod support 12 to the end engaged with the opening 2 where the hammer springs 5 are compressed, may be shorter when the hammer spring rod end 4 is at the first end A of the opening 2 of the hammer 1 compared to when it is at the second end B of the opening 2 of thehammer 1. Consequently, when the hammer 1 is engaged with the trigger 9 in the firing position, the hammer springs 5 are in a compressed state, causing the hammer 1 to pivot spontaneously when the trigger 9 is pulled, thereby partially decompressing the hammer springs 5. As the said hammer springs 5 remain partially compressed, the hammer spring guide rod end 4 within the opening 2 will spontaneously slide from the first end A to the second end B of the opening 2 of the hammer 1, allowing further decompression due to the greater distance between these ends. This results in continuous force exertion by the hammer springs 5 from a point of application at the first end A to a point at the second end B, from pulling the trigger 9 through firing and beyond. Consequently, the hammer 1 may be capable of pushing the bolt assembly 8 forward to its closed position, whether partially open or recoiled during or after firing.

[0045] In another embodiment, it is possible to remove the opening 2 and keep allowing the hammer 1 to push the bolt assembly 8 forward to its closed position utilizing the same principle of distance variation. In more detail, when the hammer 1 pivots to fire the cartridge, the distance between the two ends of the hammer spring guide rod 4, from the hammer spring guide rod support 12 to the end A where the hammer springs 5 are compressed, may be shorter when the hammer spring guide rod end 4 is at the first end A of the hammer 1 before firing, compared to after firing. Consequently, when the hammer 1 engages with the trigger 9 in the firing position, the hammer springs 5 are compressed, causing the hammer 1 to pivot spontaneously upon the trigger 9 being pulled, thereby partially decompressing the hammer springs 5. As the said hammer springs 5 remain partially compressed, the hammer spring guide rod end 4 within the end A allows further decompression due to the increased distance between these ends. This results in continuous force exerted by the hammer springs 5 at the end A, pushing the bolt assembly 8 forward and maintaining it in its closed position.

[0046] The decompression of the hammer springs 5 is ensured first by the pivoting of the hammer 1 when the trigger 9 is pulled, and second by the sliding of the hammer spring rod 4 within the hammer spring guide rod support 12 as it moves from the first end A to the second end B of the opening 2. As the effective length of compressed hammer springs 5 increases, they decompress further,exerting force to push forward the bolt assembly 8, maintain it in the closed position, or close it if partially or fully opened due to the resulting inertia from firing.

[0047] The inclusion of the opening 2 serves to enhance the decompression of the hammer springs 5. This parameter is a critical factor in the dimensioning compromise, aimed at achieving an optimal balance between maximizing the hammer spring rod 4 length and minimizing additional decompression. This balance is particularly influential in determining the angle of opening 2 within the hammer 1.

[0048] When the bolt assembly 8 is reloaded, the hammer spring guide rod end 4 remains in the second end B only at the beginning of the backward stroke of the bolt assembly 8. After approximately 10 mm of the movement of the bolt assembly 8, which involves the corresponding rotation of the hammer 1, the hammer spring guide rod end 4 returns to the first position A due to the geometry of the force balance of the system, resulting in a sudden decrease in the opening force.

[0049] In the present invention, the hammer 1 may be directly engaged with the trigger 16. Alternatively, the hammer 1 may be connected to a sear, which is actuated by a more complex separator and trigger mechanism.

Claims

Claims1. A firearm (50) comprising:- a frame (51) defined with a longitudinal axis;- a bolt assembly (8) movably mounted on the frame (51) and displaceable along the longitudinal axis between a closed position and an open position or vice versa; - a trigger pin (21) and a trigger (9) pivotally mounted upon the frame (51) by said trigger pin (21);- a hammer pin (3) and a hammer (1) pivotally mounted upon the frame (51) by said hammer pin (3), the hammer (1 ) being able to adopt a position ready for fire and a subsequent fired position, said hammer (1) comprising an elongated opening or recess (2) with a first end (A) and a second end (B);- a hammer spring guide rod (4A) provided at one end with a hammer spring guide rod end (4),- at least one hammer spring (5) mounted on said hammer spring guide rod (4A), with said at least one hammer spring (5) configured to induce movement of the hammer (1 ) between the position ready for fire and the fired position, characterized in that said hammer spring guide rod end (4) is movably mounted within the elongated opening or recess (2), with a movement from the first end (A) to the second end (B) when the hammer (1) is in the fired position, allowing the at least one hammer spring (5) to push the bolt assembly (8) forward to the closed position via the hammer (1).

2. The firearm (50) according to claim 1, wherein the at least one hammer spring (5) is configured to exert a force at a point of application located at the first end (A) when the hammer (1) is engaged with the trigger (9) in the position ready for fire.

3. The firearm (50) according to claim 2, wherein the point of application of the force of the at least one hammer spring (5) is capable of moving relative to the hammer (1 ) from the first end (A) to the second end (B) in the fired position.

4. The firearm (50) according to claims 2 and 3, wherein the force exerted by the hammer (1) on the bolt assembly (8) when the hammer spring guide rod end(4) is positioned at the second end (B) is capable of pushing forward the said bolt assembly (8) to the close position when partially recoiled in the fired position.

5. The firearm (50) according to any of preceding claims, wherein the bolt assembly (8) comprises a transverse pin (7).

6. The firearm (50) according to claim 5, wherein the hammer (1 ) is configured to contact the transverse pin (7) when the hammer (1) pushes forward the bolt assembly (8) to the closed position in the fired position.

7. The firearm (50) according to any of preceding claims, wherein the at least one hammer spring (5) is configured to be at least partially compressed when the hammer (1 ) is in the position ready for fire.

8. The firearm (50) according to any of preceding claims, wherein the at least one hammer spring (5) is configured to at least partially decompress when the hammer (1) is in the fired position, thereby pushing the hammer (1) toward the bolt assembly (8).

9. The firearm (50) according to any of the claims 5 to 8, wherein the hammer (1 ) is configured to maintain contact with the transverse pin (7) exerting forces on the bolt assembly (8) in the fired position to keep the bolt assembly (8) in the closed position.

10. The firearm (50) according to any of the preceding claims, wherein it further comprises a handcocking arm (10) and a handcocking arm pin (6) with said handcocking arm (10) pivotally mounted on the frame (51) via the handcocking arm pin (6).

11. The firearm (50) according to claim 10, wherein the hammer (1) and the handcocking arm (10) are interconnected by the hammer spring guide rod (4A).

12. The firearm (50) according to any of preceding claims, wherein the at least one hammer spring (5) is confined between the hammer (1) and a fixed point of the firearm (50).

13. The firearm (50) according to any of preceding claims, wherein the hammer spring guide rod end (4) forms a transverse extension relative to an axis of the hammer spring guide rod (4A).

Images