Adjustable firearm stock

Abstract

An adjustable stock comprises a frame and a housing that slides telescopingly with respect to the frame between at least two configurations: a shortened configuration and a lengthened configuration. Preferably there is at least one configuration of intermediate length. To permit the adjustment of the stock, a lever arm, biased in a locking position, is pressed, whereupon it unlocks the housing from the frame and allows the user to slide the housing with respect to the frame from one configuration to another. The lever arm has a projection on the end that is either seated in one of several recesses in the housing, thereby locking the frame to the housing, or slidable within a channel formed in the housing and running from one recess to another.

Description

CROSS REFERENCE TO RELATED PATENTS

None.

BACKGROUND OF THE INVENTION

The present invention relates to firearm stocks and adjustable firearm stocks in particular.

A typical rifle or machine gun will include a stock that enables the user to brace the firearm against his shoulder. The stock is fastened to a receiver and a barrel. Most stocks are sized for a typical adult and are not adjustable. Adjustable stocks are most often found in high performance, competition rifles, that allow the user to adjust the stock to the particular dimensions of the user. These adjustable stocks can be moved between a shorter configuration and a longer configuration by telescopingly sliding one part of the stock with respect to another and then securing the stock to the frame at the preferred configuration. Once fixed to the dimensions of the user, they are locked in place and only rarely adjusted a second time.

Military firearm stocks, on the other hand, may need to be configured for a particular mission, and possibly reconfigured during the mission for a change in use rather than for the body dimensions of the user. For example, a shorter stock may be preferred for its easier maneuverability in close quarters in urban fighting; a longer stock may be preferred for shooting at a distance. In either case, the adjustable stock will require some way to lock the stock in its preferred configuration. In military applications, the adjustability must be quicker and easier, driven by mission rather than the personal body dimensions of a user.

Thus there remains a need for a better way to adjust the length of a stock for military applications.

SUMMARY OF THE INVENTION

According to its major aspects and briefly recited, the present invention is an adjustable stock. The present stock comprises a frame and a housing that slides telescopingly with respect to the frame between at least two configurations: a shortened configuration and a lengthened configuration. Preferably there is at least one intermediate configuration. To permit the adjustment of the stock, a lever arm, biased in a locking position, is pressed, whereupon it unlocks the housing from the frame and allows the user to slide the housing with respect to the frame from one configuration to another. The lever arm has a projection on the end that is either seated in one of several recesses in the housing or slidable within a channel formed in the housing and running from one recess to another.

An important feature of the present invention is the locking lever, which allows the user to quickly, reliably and easily change the configuration of the stock. Merely by squeezing the locking lever, the user is able to unlock the housing with respect to the frame. Releasing the locking lever assures that the housing and frame will lock when they in one of the configurations.

Another important feature of the present invention is the combination of a pin positioned in the stock that prevents excessive rearward movement of the locking lever, the projection on the end of the lever, and the channel the projection slides in when the housing is moved relative to the frame. Only a small amount of travel of the locking lever is required to move the projection out of its recess and thereby unlock the housing from the frame; excessive movement of the locking lever, if permitted, would cause the projection on the lever to become misaligned with respect to the channel. The pin in the stock prevents excessive movement of the locking lever, and, accordingly, misalignment. Additionally, the channel assures controlled movement of the projection from one locking position to the next.

These and other features and their advantages will be apparent to those skilled in the art of firearm design from a careful reading of the Detailed Description of Preferred Embodiments accompanied by the following drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

In the drawings,

FIG. 1A is a perspective view of a firearm with a stock according to a preferred embodiment of the present invention, the stock in the shortened configuration;

FIG. 1B is a detail of the firearm of FIG. 1A showing the stock in a lengthened configuration;

FIG. 2 is a side exterior view of the stock in the shortened configuration with its locking lever pulled, according to a preferred embodiment of the present invention

FIG. 3 is a side exterior view of the stock of FIG. 2 in the extended configuration and with its locking lever released;

FIG. 4 is a side cross sectional view of the shortened stock of FIG. 2; and

FIG. 5 is a side cross sectional view of the lengthened stock of FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a new, replacement stock for an existing firearm and a new firearm equipped with the present stock. The stock is characterized by the fact that the user can quickly and easily lengthen and shorten the stock without tools.

Referring now to the figures, FIG. 1A illustrates a light-weight machine gun 10 having a barrel 12, a receiver 14, and a stock 16. Barrel 12 has a receiver end 22 connected to a first end 24 of receiver 14. An opposing, second end 26 of receiver 14 is attached to a first end 28 of stock 16. Ammunition (not shown) is inserted into a breech 30 of receiver 14 and fired through barrel 16 in the usual manner using a fire control system. Except for a portion of trigger 18, the fire control system is housed in receiver 14.

Although FIG. 1A shows light-weight machine gun 10, any firearm capable of having a stock attached to it may be improved with the present stock 16. Furthermore, the operation and construction of firearms, particularly standard military rifles and machine guns, are well known.

FIG. 1B illustrates a detailed view of a firearm focused on stock 16 and a portion of receiver 14. It will be clear from a comparison of stock 16 in FIGS. 1A and 1B that stock 16 in FIG. 1A is shorter and stock 16 in FIG. 1B is longer. In particular, stock 16 has a frame 32 and a housing 34 slidably carried by frame 32. Housing 34 slides over frame 32 in a telescoping fashion between a shortened configuration, as illustrated in FIG. 1A, and a lengthened configuration, as illustrated in FIG. 1B. As will be described, stock 16 may have at least one intermediate configuration.

Stock has a cheek piece 36 and butt plate 38, a rear sling attachment 40 and a front sling attachment 42. When first end 28 of stock 16 is disconnected from second end 26 of receiver 14, a receiver coupler 44 can be seen with an upper pin connection 46 and a lower pin connection 48. A portion of a locking lever 56 is visible along the bottom of frame 32. Acting somewhat like a trigger that can be pulled or squeezed to release the internal locking mechanism and thereby allow the reconfiguration of stock 16 between the shortened configuration, as shown in FIG. 1A as well as FIG. 2 and FIG. 4, and the lengthened configuration, as shown in FIG. 1B, FIG. 3 and FIG. 5.

The cross sectional views of FIGS. 4 and 5 illustrate the operation of the locking mechanism. As the user squeezes exterior portion 60 of locking lever 56, locking lever 56 pivots about a pivot pin 62. Its distal end 64 rotates counter-clockwise when stock 16 is viewed from the left and pulls a projection 66 carried on its distal end downward and out of a recess 68 formed in a channel 70 in frame 32. Once projection 66 is clear of recess 68, housing 34 is free to slide with respect to frame 32. When housing 34 is sliding, projection 66 remains within channel 70, and thus channel 70 acts as a guide or cam race for projection 66, keeping it confined to a narrow track. Projection 66 thus serves two functions. First, when in recess 68, it holds frame 32 locked to housing 34. Second, when out of recess 68 but still in channel 70, it serves as a cam, an alignment device, to keep housing 34 aligned with frame 32 when the two are moving relative to each other.

It is important for alignment and repeatable operation of frame 32 and housing 34 of stock 16 to limit the travel of exterior portion 60 of locking pin 56 so that projection 66 does not pivot clear of channel 70. It is also important to urge projection 66 into recess 68. Therefore, a retaining pin 76 biased by a spring 78 is positioned behind exterior portion 60 to limit its rearward travel and urge it forward. When locking lever 56 is pressed against a first end retaining pin 76, pin 76 moves rearward against the urging of spring 78 until pin meets butt plate 38, whereupon it and locking lever 56 can move no further.

It is intended that the scope of the present invention include all modifications that incorporate its principal design features, and that the scope and limitations of the present invention are to be determined by the scope of the appended claims and their equivalents. It also should be understood, therefore, that the inventive concepts herein described are interchangeable and/or they can be used together in still other permutations of the present invention, and that other modifications and substitutions will be apparent to those skilled in the art from the foregoing description of the preferred embodiments without departing from the spirit or scope of the present invention.

Claims

1. A stock for a firearm, said stock comprising: a frame; a housing slidably carried by said frame between a shortened configuration and a lengthened configuration; a locking lever pivotally carried by said housing and pivotable between at least one locking position and an unlocking position, said locking lever locking said frame to said housing when said locking lever is in said at least one locking position; and means for urging said locking lever into said at least one locking position, said urging means limiting movement of said locking lever from said at least one locking position to said unlocking position.

2. The stock as recited in claim 1, wherein said locking lever is adapted to lock said frame to said housing in said shortened configuration and in said lengthened configuration.

3. The stock as recited in claim 1, wherein said frame has two recesses formed therein and said locking lever carries a projection, each recess of said two recesses dimensioned for receiving said projection, said locking lever locking said frame to said housing when said projection is received within said each recess.

4. The stock as recited in claim 1, wherein said urging means further comprises: a pin; a spring; and a butt plate, said spring urging said locking lever into said locking position and said pin limiting movement of said locking lever when said pin meets said butt plate.

5. The stock as recited in claim 1, wherein said locking lever has a first end and an opposing second end, said first end extending outside of said housing, said second end being inside said housing.

6. The stock as recited in claim 5, wherein said second end carries a projection and said frame has at least two recesses, said projection of said locking lever being received by either recess of said at least two recesses when said frame is locked to said housing.

7. The stock as recited in claim 6, wherein said frame has a channel formed therein and running between said at least two recesses, and wherein said projection moves within said channel when said frame is moving with respect to said housing.