Mechanism for locking and adjusting the assembly tension of the stock to a receiver of a firearm

• US 7,866,078 B1
• Filed: 10/03/2007
• Issued: 01/11/2011
• Est. Priority Date: 10/17/2006
• Status: Expired due to Fees

• Current Assignee: Fabbrica D'Armi Pietro Beretta SPA (Upifra SA)
• Original Assignee: Fabbrica D'Armi Pietro Beretta SPA (Upifra SA)
• Inventors: Beretta, Ugo Gussalli
• Primary Examiner(s): JOHNSON, STEPHEN
• Application Number:
  US11/906,684
• Time in Patent Office: 1,196 Days
• Field of Search: 42/750.1, 42/750.3
• US Class Current: 42/75.03
• CPC Class Codes: F41C 23/14 Adjustable stock or stock parts, i.e. adaptable to personal requirements, e.g. length, pitch, cast or drop

Abstract

A mechanism (40) for locking and adjusting the assembly tension of the stock (20) to a receiver (12) of a firearm (10), characterized in that it comprises locking and tensioning means (50) integrally connected in an swinging manner to the stock (20) and in turn provided with a contact profile (51) adapted to be commanded in rotation around a hinging pin (41) and an engagement portion (54) adapted to cooperate with a stock bolt (16) integral with the receiver (12), in order to make said locking and tensioning means (50) pass, following the rotation of the contact profile, from an unlocked position of the stock bolt (16) to an engagement position of said stock bolt with increasing tension, and vice versa.

Claims

1. An adjustable locking device for locking and adjusting the assembly tension between a stock (20) and a frame (12) of a firearm (10), characterised in that said adjustable locking device comprises a stirrup (50) connected by a hinging pin (41) to the stock (20) where said stirrup (50) is provided with a contact profile (51) and said stirrup (50) is adapted to be commanded in rotation around a said hinging pin (41), said stirrup having an engagement portion (53) in the form of a fork (54) adapted to cooperate with a stock bolt (16) connected to the receiver (12), said contact profile (51) being adapted to receive a thrust from a screw (60) that causes said stirrup (50) to rotate around hinging pin (41), from an unlocked position of the stirrup (50) to an engagement position of said stirrup (50) on the stock bolt (16) wherein the tension between the stirrup (50) and the stock bolt (16) is increased by the rotation of the stirrup, and when the thrust from screw (60) is reversed, to rotate from the engagement position where said stirrup (50) is in tension with said stock bolt (16) to the unlocked position.

2. An adjustable locking device according to claim 1, wherein said stirrup (50) in which the engagement portion (53) is made in the form of a fork (54) said fork (54) having a pair of tips (55) adapted to retain a head (17) located at the terminal portion of the stock bolt (16), wherein said terminal portion of stock bolt (16) has adjacent to said terminal portion a neck (18) of lower diameter prearranged for receiving a groove (56) located between said pair of tips (55).

3. An adjustable locking device according to claim 2, wherein said stirrup (50) is centrally equipped with an extended portion formed by two parallel arches (57), separated by a slot (58), said arches (57) being connected to the contact profile (51) and being crossed by a pair of holes (59) for the insertion of the hinging pin (41).

4. An adjustable locking device according to claim 3, wherein the slot (58) is adapted for housing a coil spring (42) wound on the pin (41) and adapted to bring the stirrup back to the unlocked position.

5. An adjustable locking device according to claim 4, wherein the screw (60) which is provided for thrust driving the contact profile (51) for the rotation of the stirrup (50), has a force application point on the stirrup (50) which is misaligned with respect to the rotation axis of the pin (41).

6. An adjustable locking device according to claim 5, wherein the stirrup (50) is housed within a bush (43) to be inserted within a cylindrical slot (33) made in the stock (20).

7. An adjustable locking device according to claim 6, wherein said stock (20) has a shaped seat (30) made in a pistol grip (22) on said stock (20) and comprises a chamber (31) which leads to a base of the pistol grip (22) where said pistol grip (22) is connected on an upper part to said cylindrical slot (33) inside the stock.

8. An adjustable locking device according to claim 7, wherein said bush (43) comprises a hollow cylindrical body equipped with side openings (47) for the passage of the stock bolt (16), and equipped at the base with a tooth (45) and an eyelet (44) adapted to receive a check bottom plate (61) adapted to retain the screw (60), preventing said screw (60) from disengagement from the bush.

9. An adjustable locking device according to claim 8, wherein said tooth (45) is provided which can be coupled by a hook (63) provided on the bottom plate (61) while a perforated plate (62) is provided for to correspond with the eyelet (44) for the passage of a fixing screw of the bottom plate of the bush that bears the stirrup (50) on the stock of a long gun.

10. An adjustable locking device according to claim 9, wherein said bottom plate (61) has an opening (64) for the passage of a suitable key (80) adapted to engage the screw (60) for adjusting the tightening tension or for unlocking the stock.

11. An adjustable locking device according to claim 10, wherein a plug (70) is provided for closing said chamber (31), said plug (70) being equipped with a spring door (71) which closes the bottom of the pistol grip (22) and when said spring door is open the screw (60) is directly drivable with said key (80).