IP Library › Granted Patent US 11,280,570
Granted Patent B2
US 11,280,570 · App. 16/815,993 · Granted Mar 22, 2022

Firearm operating mechanisms and bolt release

Inventors: James Matthew Underwood (Kennesaw, GA); Larry Cullen Underwood (Canton, GA)
F41A19/10F41A19/25F41A19/43F41A19/14
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Quick Facts
Patent No.
US 11,280,570
App. No.
16/815,993
Granted
Mar 22, 2022
Kind
B2
Abstract

An operating system for a firearm includes a trigger, a hammer, a disconnector, a pivoting arm, and a lower member. The trigger includes a lower portion, an upper portion, and a trigger pivot. The disconnector includes a lower portion, an upper portion, and a disconnector pivot. The pivoting arm includes a forward protrusion, a pivoting arm opening, and a pin extending through the pivoting arm opening. The lower member includes a lower member opening and a pin hole that is coaxial with the trigger pivot and the disconnector pivot. At least a portion of the trigger and at least a portion of the disconnector are disposed within the lower member opening. Motion of the trigger causes the forward protrusion of the pivoting arm to engage a bolt carrier group and hold the bolt carrier group in an open position.

Claims (36)

1. An operating system disposed within a receiver of a firearm, the operating system comprising:

a trigger comprising a lower portion, an upper portion, and a trigger pivot;

a hammer comprising a hammer pivot;

a disconnector comprising a lower portion, an upper portion, and a disconnector pivot;

a pivoting arm comprising a forward protrusion, a pivoting arm opening, and a pin extending through the pivoting arm opening, wherein at least a portion of the hammer and at least a portion of the disconnector are disposed within the pivoting arm opening; and

a lower member comprising a lower member opening and a pin hole that is coaxial with the trigger pivot and the disconnector pivot, wherein at least a portion of the trigger and at least a portion of the disconnector are disposed within the lower member opening,

wherein motion of the trigger causes the forward protrusion of the pivoting arm to engage a bolt carrier group of the firearm and hold the bolt carrier group in an open position.

2. The operating system of claim 1 , wherein the pivoting arm is attached to the lower member by a rotation pin and wherein at least a portion of the pivoting arm is disposed within the lower member opening.

3. The operating system of claim 1 , wherein motion of the trigger results in pressure on the pivoting arm pin causing the pivoting arm to move upward and engage the bolt carrier group of the firearm.

4. The operating system of claim 3 , wherein releasing the trigger causes the pivoting arm to move downward and disengage the bolt carrier group of the firearm.

5. The operating system of claim 3 , wherein a subsequent trigger actuation causes the pivoting arm to move downward and disengage the bolt carrier group of the firearm.

6. The operating system of claim 1 , further comprising a disconnector plate, a cam, and a reset arm, wherein:

the disconnector plate is disposed adjacent to the disconnector and comprises a pivot hole that is coaxial with the trigger pivot and the disconnector pivot;

the cam comprises (i) a nose that interfaces with a rear interface portion of the disconnector plate and (ii) a cam pivot that is coaxial with a pin connection between the pivoting arm and the lower member; and

the reset arm comprises a notch that interfaces with a tooth of the cam.

7. The operating system of claim 1 , wherein the hammer pivot is coaxial with a forward pivot hole of the lower member.

8. The operating system of claim 1 , wherein the forward protrusion of the pivoting arm interfaces with a bolt release of the firearm.

9. The operating system of claim 1 , wherein the pivoting arm comprises at least one upward protrusion, wherein the at least one upward protrusion is configured to contact an underside of the bolt carrier group of the firearm.

10. An operating system disposed within a receiver of a firearm, the operating system comprising:

a trigger comprising a lower portion, an upper portion, and a trigger pivot;

a hammer comprising a hammer pivot;

a disconnector comprising a lower portion, an upper portion, and a disconnector pivot;

a lower member comprising a lower member opening; and

a pivoting arm comprising a forward protrusion, a pivoting arm opening, and a pin extending through the pivoting arm opening, wherein:

the pivoting arm is pivotably attached to the lower member; and

motion of the trigger causes the forward protrusion of the pivoting arm to engage a bolt carrier group of the firearm and hold the bolt carrier group in an open position.

11. The operating system of claim 10 , wherein motion of the trigger results in pressure on the pivoting arm pin causing the pivoting arm to move upward and engage the bolt carrier group of the firearm.

12. The operating system of claim 11 , wherein releasing the trigger causes the pivoting arm to move downward and disengage the bolt carrier group of the firearm.

13. The operating system of claim 11 , wherein a subsequent trigger actuation causes the pivoting arm to move downward and disengage the bolt carrier group of the firearm.

14. The operating system of claim 10 , further comprising a disconnector plate, a cam, and a reset arm, wherein:

the disconnector plate is disposed adjacent to the disconnector and comprises a pivot hole that is coaxial with the trigger pivot and the disconnector pivot;

the cam comprises (i) a nose that interfaces with a rear interface portion of the disconnector plate and (ii) a cam pivot that is coaxial with a pin connection between the pivoting arm and the lower member; and

the reset arm comprises a notch that interfaces with a tooth of the cam.

15. The operating system of claim 10 , wherein the hammer pivot is coaxial with a forward pivot hole of the lower member.

16. The operating system of claim 10 , wherein the forward protrusion of the pivoting arm interfaces with a bolt release of the firearm.

17. The operating system of claim 10 , wherein the pivoting arm comprises at least one upward protrusion, wherein the at least one upward protrusion is configured to contact an underside of the bolt carrier group of the firearm.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 16, 2020
From: UNDERWOOD, JAMES MATTHEW; UNDERWOOD, LARRY CULLEN
To: MEAN L.L.C.
Reel/Frame 052412/0790 →
Continuity (2)
Provisional Application 62816476 · Mar 11, 2019
Related Publication 20200292266A1 · Sep 17, 2020
Cited By (3)
US 12,241,703 US 12,305,943 US 12,710,241