Folding stock coupling system for firearm

Patent metadata

Field	Value
Publication number	US-11543208-B2
Application number	US-202117192173-A
Country	US
Kind code	B2
Filing date	Mar 4, 2021
Priority date	Mar 6, 2020
Publication date	Jan 3, 2023
Grant date	Jan 3, 2023

Abstract

A folding stock coupling system for a firearm. An openable/closeable hinge mechanism comprising front and rear hinge elements pivotably mounts the rear stock to the main body of the firearm. The hinge mechanism is selectively movable between a locked condition when the stock is unfolded and inline with the main body for firing, and an unlocked condition when the stock is folded forward and offset from the main body for compact carrying or storage. A manually movable actuating button of the hinge mechanism selectively locks or unlocks the rear to the front hinge members in the locked and unlocked conditions, respectively. Embodiments include a detent mechanism for removably retaining the folded position. An elongated rear mounting extension coupled to the rear hinge member provides a common stock mounting interface compatible for interchanging a plurality of different stocks to the firearm each sharing a common mounting profile.

First claim

What is claimed is:

1. A stock coupling system for a firearm, the stock coupling system comprising:
a longitudinal axis;
a hinge mechanism comprising a front hinge member configured to be fixedly coupled to a main body of the firearm, and a rear hinge member pivotably coupled to front hinge member;
the hinge mechanism selectively movable between a locked condition in which the rear hinge member is not movable relative to the front hinge member, and an unlocked condition in which the rear hinge member is movable relative to the front hinge member;
an actuating button movably mounted to the hinge mechanism, the actuating button being configured to lock the rear hinge member to the front hinge member in the locked condition of the hinge mechanism;
an elongated rear mounting extension coupled to the rear hinge member, the rear mounting extension configured to detachably couple a rear stock thereto; and
a retention plate fixedly coupling the rear mounting extension to the rear hinge member via a pair of fasteners passing through the rear hinge member and rear mounting extension to threadably engage the retention plate.

2. The system according to claim 1 , wherein the actuating button is slideably mounted to the rear hinge member and manually depressible.

3. The system according to claim 2 , wherein the actuating button is linearly movable between an outward position in which the actuating button is lockingly engaged with the front hinge member and an inward position disengaged from the front hinge member.

4. The system according to claim 3 , further comprising an operating spring which biases the actuating button towards the outward position.

5. The system according to claim 3 , wherein the actuating button comprises a pair of first tapered locking surfaces mutually engageable with a corresponding pair of second tapered locking surfaces of the front hinge member when the actuating button is in the outward position.

6. The system according to claim 5 , wherein the first tapered surfaces are spaced apart on first locking protrusions formed on the actuating button and the second tapered surfaces are correspondingly spaced apart on hook-shaped second locking protrusions on the front hinge member to create a balanced locking force therebetween when the hinge mechanism is in the locked condition.

7. The system according to claim 6 , wherein the second locking protrusions each define an inwardly open locking recess which receives and lockingly engages one of the first locking protrusions of the actuating button when the hinge mechanism is in the locked condition.

8. The system according to claim 7 , wherein the actuating button further comprises an elongated body slideably received in a corresponding receptacle in the rear hinge member, and an enlarged actuating end at one end of the body protruding outwards from the rear hinge member configured to be pressed by a user.

9. The system according to claim 8 , wherein the actuating end of actuating button is nested between the second locking protrusions of the front hinge member when the hinge mechanism is in the locked condition.

10. The system according to claim 1 , wherein the retention plate further comprises a retention protrusion which engages a corresponding retention tab on the actuating button to prevent ejection of the actuating button by the operating spring.

11. The system according to claim 1 , wherein the rear mounting extension is pivotable between an inline position in which a stock axis of the stock is inline with the longitudinal axis and an offset position in which the stock axis is laterally offset from the longitudinal axis.

12. The system according to claim 1 , wherein a lower portion of the rear mounting extension includes a plurality of longitudinally spaced apart indexed mounting holes, the stock being mountable to the rear mounting extension via a fastener or pin engageable with a selected one of the mounting holes to allow a user to adjust a length of pull of the stocks.

13. The system according to claim 1 , wherein the rear hinge member comprises an elongated hinge arm defining a tubular hinge barrel which is pivotably coupled to the front hinge member by a hinge pin.

14. The system according to claim 13 , further comprising a detent mechanism comprising:
the hinge barrel including a detent protrusion defining a pair of tapered first detent surfaces selectively engageable with a corresponding pair of tapered detent surfaces formed in a detent recess of the front hinge member to retain the rear mounting extension in the offset position; and
a spring which biases the detent protrusion into the detent recess.

15. The system according to claim 1 , wherein the front hinge member comprises a tightenable clamp assembly configured for detachable coupling to a rail on the rear end of the main body of the firearm.

16. The system according to claim 1 , wherein:
the rear mounting extension comprises a common mounting interface configured to be interchangeably coupled to a plurality of different rear stocks to the hinge mechanism; and
the rear mounting extension being configured for slideable insertion into a forwardly open longitudinal passageway of common cross-sectional configuration formed in each of the plurality of stocks.

17. The system according to claim 16 , wherein a first stock of the plurality of stocks has a first characteristic and a second stock of the plurality of stocks has a second characteristic different than the first characteristic.

18. A firearm with interchangeable stock coupling system comprising:
a main body comprising a longitudinal axis;
a hinge mechanism comprising a front hinge member fixedly coupled to the main body, and a rear hinge member pivotably coupled to front hinge member;
the hinge mechanism selectively movable between a locked condition in which the rear hinge member is not movable relative to the front hinge member, and an unlocked condition in which the rear hinge member is movable relative to the front hinge member;
an elongated rear mounting extension projecting rearward from the rear hinge member;
a first stock slideably coupled to the rear mounting extension, the stock slideable between a plurality of axial positions on the rear mounting extension for adjusting a length of pull of the firearm;
an actuating button movably mounted to the hinge mechanism, the actuating button being configured to lock the rear hinge member to the front hinge member in the locked condition of the hinge mechanism; and
a retention plate fixedly coupling the rear mounting extension to the rear hinge member via a pair of fasteners passing through the rear hinge member and rear mounting extension to threadably engage the retention plate;
wherein the first stock is movable between an unfolded position in which the first stock is inline with the longitudinal axis when the hinge mechanism is in the locked condition, and a folded position in which the first stock is laterally offset from the longitudinal axis when the hinge mechanism is in the unlocked condition.

19. The firearm according to claim 18 , wherein the actuating button is linearly movable between an outward position in which the actuating button is lockingly engaged with the front hinge member and an inward position disengaged from the front hinge member; and further comprising an operating spring which biases the actuating button towards the outward position.

20. The firearm according to claim 19 , wherein the actuating button comprises a pair of first tapered locking surfaces

Assignees

• Sturm Ruger & Comany Inc
• Sturm Ruger & Co

Inventors

• Saunders Frank J
• Wilkinson Todd
• Hawkins Benjamin Gerard

Classifications

• F41C23/14

  Adjustable stock or stock parts, i.e. adaptable to personal requirements, e.g. length, pitch, cast or drop · CPC title

• F41C23/04 Primary

  Folding or telescopic stocks or stock parts (articulated or collapsible guns F41A11/04) · CPC title