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 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 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

Field 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] 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

[0005] The present invention aims to provide a firearm featuring an anti-opening bolt assembly system utilizing the hammer. This system incorporates a guide rod that slides within an opening 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 within the hammer's opening from the first end to the second end, maintaining the hammer spring under compression.

[0006] 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 comprising an opening with a first end A and a second end B; a hammer spring guide rod and hammer springs acting into the opening of the hammer via said hammer spring guide rod for causing movement of the hammer along a path to cock the firearm and to close the bolt assembly; wherein, the hammer spring guide rod is movable from the first end A to the second end B of the opening of the hammer after firing, allowing the hammer springs to push the bolt assembly forward to the closed position via the hammer.

[0007] Preferably, the hammer springs are configured to exert a force at a point of application located at the first end A when the hammer is engaged with the trigger.

[0008] Preferably, the point of application of the force of the hammer springs is capable of moving relative to the hammer from the first end A to the second end B after firing.

[0009] Preferably, the force exerted by the hammer on the bolt assembly when the hammer spring guide rod 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.

[0010] Preferably, the bolt assembly comprises a transverse pin.

[0011] 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.

[0012] Preferably, the hammer springs are capable of at least partially compressing when the hammer is engaged with the trigger.

[0013] Preferably, the hammer springs are capable of at least partially decompressing when the hammer is cocked, thereby pushing the hammer toward the bolt assembly.

[0014] 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.

[0015] 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.

[0016] Preferably, the hammer and the handcocking arm are interconnected by the hammer spring guide rod.

[0017] Preferably, the hammer springs are mounted on the hammer spring guide rod and confined between the hammer and the handcocking arm.

[0018] Preferably, the hammer springs are at least partially compressed when engaged with the trigger.

[0019] Preferably, the hammer springs are partially decompressed after firing.

[0020] Preferably, the hammer spring guide rod 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

[0021] Figure 1 is a cross-sectional view of the firearm and a zoom-in of the percussion system before firing. Figure 2 is a 3D view representing the percussion mechanism. Figure 3 is a cross-sectional view of the firearm and a zoom-in of the anti-opening bolt assembly system after firing. Detailed description of the invention

[0022] 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 principle applies when combining elements from the figures that illustrate the principal component of the current invention.

[0023] The expression "opening" 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.

[0024] 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.

[0025] 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 cocking. 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.

[0026] Figure 1 further depicts the firearm 50 in its charged state, referred to as the firing position, where the hammer 1 is engaged with the trigger 9 and the hammer springs 5 are at least partially compressed. The hammer 1 comprises a linear opening 2 extending between a first end A and a second end B, accommodating the hammer spring guide rod 4. In more detail, in the firing position of the firearm 50, the hammer spring guide rod 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.

[0027] 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 4 between its first end A and second end B. The opening 2 is preferably configured as a channel.

[0028] Figure 1 further illustrates a handcocking arm 10 linked to the hammer 1 by the hammer spring guide rod 4, 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.

[0029] 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.

[0030] 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 4 are consistently applied on the hammer 1 at either the first end A or the second end B of the opening 2.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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 4 is connected to the hammer 1 through the opening 2, enabling movement along its entire length from one end to the other.

[0035] 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 hammer spring 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 end of the hammer spring guide rod 4 within the opening 2 to exert forces at a designated point in the first end A of said opening 2.

[0036] In an alternative embodiment, a varied configuration of the opening 2 may be machined into the body of the hammer 1. More importantly, this machined shape within the body of the hammer 1 should enable at least partial accommodation of the end of the hammer spring guide rod 4 inside the opening 2, facilitating displacement from the first end A to the second end B within the opening 2 during the firing of the hammer 1. The opening 2 may also take the form of a non-through opening or groove.

[0037] 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 end of the hammer spring guide rod 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.

[0038] 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.

[0039] 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.

[0040] 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 end of the hammer spring rod 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 the hammer 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 end of the hammer spring guide rod 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.

[0041] 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 end of the hammer spring rod 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 end of the hammer spring guide rod 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.

[0042] 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.

[0043] 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.

[0044] When the bolt assembly 8 is reloaded, the hammer spring rod 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 rod 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.

[0045] 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

1. 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) comprising an opening (2) with a first end (A) and a second end (B); - a hammer spring guide rod (4) and hammer springs (5) acting into the opening (2) of the hammer (1) via said hammer spring guide rod (4) for causing movement of the hammer (1) along a path to cock the firearm (50) and to close the bolt assembly (8); wherein, the hammer spring guide rod (4) is movable from the first end (A) to the second end (B) of the opening (2) of the hammer (1) after firing, allowing the hammer springs (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 hammer springs (5) are 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).

3. The firearm (50) according to claim 2, wherein the point of application of the force of the hammer springs (5) is capable of moving relative to the hammer (1) from the first end (A) to the second end (B) after firing.

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 (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 during or after firing.

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 capable of contacting the transverse pin (7) when the said hammer (1) pushes forward the bolt assembly (8) to the closed position after firing.

7. The firearm (50) according to any of preceding claims, wherein the hammer springs (5) are capable of at least partially compressing when the hammer (1) is engaged with the trigger (9).

8. The firearm (50) according to any of preceding claims, wherein the hammer springs (5) are capable of at least partially decompressing when the hammer (1) is cocked, 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) maintains contact with the transverse pin (7) exerting forces on the bolt assembly (8) after firing to keep the said 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 (4).

12. The firearm (50) according to claim 11, wherein the hammer springs (5) are mounted on the hammer spring guide rod (4) and confined between the hammer (1) and the handcocking arm (10).

13. The firearm (50) according to claim 12, wherein the hammer springs (5) are at least partially compressed when engaged with the trigger (9).

14. The firearm (50) according to claims 12 and 13, wherein the hammer springs (5) are partially decompressed after firing.

15. The firearm (50) according to any of the preceding claims, wherein the hammer spring guide rod (4) engages with the opening (2) to move from the first end (A) to the second end (B) when the hammer (1) is disengaged from the trigger (9).

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