The invention concerns trigger and trigger bar assemblies used with firearms.
Trigger return springs of the extension or torsion type, used in semiautomatic pistols, are subject to relatively high stress reversals (alternating compression and tension stress). As the paramount design parameter of such a spring is its stiffness, the design of the spring cannot generally take the spring's fatigue life into account. Extension and torsion springs may thus suffer from premature fatigue failure. It would be advantageous to use a compression spring to mitigate fatigue failure and increase the fatigue life of trigger return springs.
This invention concerns a trigger return spring assembly for a firearm. In this example embodiment, the trigger return spring assembly comprises a trigger, a trigger bar, a bore, a shoulder, a plunger and a spring. The trigger is mountable on the frame for pivoting motion about a first axis of rotation fixed on the frame. The trigger bar is attached to the trigger and is pivotable relatively thereto about a second axis of rotation fixed on the trigger. The bore extends through the trigger along a third axis oriented transversely to and positioned between the first and second axes of rotation. The shoulder is positioned within the bore proximate to the trigger bar. The plunger extends through the bore and is movable along the third axis. A first end of the plunger is attached to the trigger bar, and a second end of the plunger comprises a retaining surface oriented transversely to the third axis. The compression spring is captured within the bore between the shoulder and the retaining surface. The compression spring exerts a force pushing the retaining surface away from the shoulder.
In an example, the first end of the plunger terminates in a first head and the second end terminates in a second head. In a particular example, the retaining surface is located on the second head facing the spring. In another particular example, the second head is rotatable about a fourth axis transverse to the third axis. In a particular example, the assembly further comprise a yoke mounted on the trigger bar. In this example, the first head pivotally engages the yoke.
As an example, the assembly further comprises a first pin which attaches the trigger bar to the trigger. In an example, the assembly further comprises a second pin which attaches the trigger to the frame.
This invention also concerns a firearm. In this example embodiment, the firearm comprises a frame. A trigger return spring assembly comprises a trigger, a trigger bar, a bore, a shoulder, a plunger, and a compression spring. The trigger is mounted on the frame for pivoting motion about a first axis of rotation about the frame. The trigger bar is attached to the trigger pivotable relatively thereto about a second axis of rotation fixed on the trigger. The bore extends through the trigger along a third axis oriented transversely to and positioned between the first and second axes of rotation. The shoulder is positioned within the bore proximate to the trigger bar. The plunger extends through the bore and is movable along the third axis. A first end of the plunger is attached to the trigger bar, and a second end of the plunger comprise a retaining surface oriented transversely to the third axis. The compression spring is captured within the bore between the shoulder and the retaining surface. The compression spring exerts a force which pushes the retaining surfaced away from the shoulder.
In an example, the first end of the plunger terminates in a first head and the second end terminates in a second head. In a particular example, the retaining surface is located on the second head facing the spring. In another particular example, the second head is rotatable about a fourth axis transverse to the third axis. In a particular example, the assembly further comprise a yoke mounted on the trigger bar. In this example, the first head pivotally engages the yoke.
As an example, the assembly further comprises a first pin which attaches the trigger bar to the trigger. In an example, the assembly further comprises a second pin which attaches the trigger to the frame.
As shown in
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Also shown in
The assembly 10 may further comprise a yoke 46 mounted on the trigger bar 18. The first head 42 pivotally engages the yoke 46. The pivoting of the first head 42 within the yoke 46 accommodates the offset of the first head 42 from the third axis 26 due to the rotation of the trigger 16 about the first axis 20.
The assembly 10 may also further comprise a first pin 48 which attaches the trigger bar 18 to the trigger 16, advantageously facilitating the pivoting of trigger bar 18 relative to the trigger 16 about the second axis of rotation 22. As shown in
In use force is applied to trigger 16 rotating it about the axis of rotation 20 in a direction of trigger bar 18. As trigger 16 rotates from the “ready” position the trigger bar 18, pivotally connected to trigger 16 by the first pin 48, moves in a direction 54 away from the trigger 16. As the trigger bar 18 moves the yoke 46, first head 42, and plunger 30 also move further compressing spring 40 between the retaining surface 36 and shoulder 28. When the force is released from trigger 16 the compressed spring 40 exerts a force pushing the retaining surface 36 away from the shoulder 28 returning the trigger 16 to the “ready” position.
The firearm 10 with the trigger return spring mechanism 14 described herein is expected to mitigate fatigue failure and increase the fatigue life of trigger return springs.
This application is based upon and claims benefit of priority to U.S. Provisional Application No. 62/910,516, filed Oct. 4, 2019, the application being hereby incorporated by reference.
Number | Date | Country | |
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62910516 | Oct 2019 | US |