Abstract
Firearm control mechanisms have a frame, a trigger element connected to the frame and movable with respect to the frame, a selector connected to the frame and pivotable with respect to the frame about a pivot axis, the selector including a first cam surface operably engaged to a follower portion of the trigger element, the selector having a detent portion having a detent surface opposing a spring biased detent follower connected to the frame and operable to reciprocate against the detent surface, the detent surface having a plurality of stable positions, each corresponding to an operating condition of the fire control mechanism, and the detent portion being a body lacking any concave surfaces. The detent surface may have a plurality of flat cam surfaces. At least two of the flat cam surfaces may be perpendicular to each other. A corner may join the plurality of flat cam surfaces.
Claims
1. A firearm control mechanism comprising: a frame; a trigger element connected to the frame and movable with respect to the frame; a selector connected to the frame and pivotable with respect to the frame about a pivot axis; the selector including a first cam surface operably engaged to a follower portion of the trigger element; the selector having a detent portion having a detent surface opposing a spring biased detent follower connected to the frame and operable to reciprocate against the detent surface; the detent surface having a plurality of stable positions; the selector including a stop surface limiting the selector to a limited range of pivoting; and the detent portion being a body lacking any concave surfaces.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a front isometric view of a prior art trigger group for semi-automatic firearms that includes a selector used with a spring-loaded detent.
[0021] FIG. 2 is right side view of the current embodiment of a firearm control mechanism constructed in accordance with the principles of the present invention installed in a rifle.
[0022] FIG. 3 is an exploded view of the firearm control mechanism of FIG. 1.
[0023] FIG. 4 is a front isometric view of a safety selector shaft of the selector of FIG. 1 along with a spring-loaded detent.
[0024] FIG. 5 is a front view of the safety selector shaft along with a spring-loaded detent.
[0025] FIG. 6 is a front isometric view of the safety selector shaft along with a spring-loaded detent.
[0026] FIG. 7A is a side sectional view of the safety selector shaft and spring-loaded detent with the safety selector shaft selecting a first mode of operation.
[0027] FIG. 7B is a side sectional view of the safety selector shaft and spring-loaded detent with the safety selector shaft having rotated counterclockwise relative to the position shown in FIG. 7A to begin transitioning to selecting a second mode of operation.
[0028] FIG. 7C is a side sectional view of the safety selector shaft and spring-loaded detent with the safety selector shaft having rotated counterclockwise relative to the position shown in FIG. 7B to further transition to selecting a second mode of operation.
[0029] FIG. 7D is a side sectional view of the safety selector shaft and spring-loaded detent with the safety selector shaft having rotated counterclockwise relative to the position shown in FIG. 7C and 90° relative to the position shown in FIG. 7A to fully transition to selecting a second mode of operation.
[0030] FIG. 8 is a front view of the safety selector shaft along with a spring-loaded detent.
[0031] FIG. 9 is a side sectional view of the safety selector shaft and spring-loaded detent installed in a rifle.
[0032] FIG. 10 is a front sectional view of the safety selector shaft and spring-loaded detent installed in a rifle.
[0033] FIG. 11 is a top view of the safety selector shaft.
[0034] FIG. 11A is a side sectional view taken along line 11A-11A of FIG. 11.
[0035] FIG. 11B is a side sectional view taken along line 11B-11B of FIG. 11.
[0036] FIG. 11C is a side sectional view taken along line 11C-11C of FIG. 11.
[0037] FIG. 11D is a side sectional view of the sections in FIGS. 11A-11C overlaid in axial registration with one another.
[0038] The same reference numerals refer to the same parts throughout the various figures.
DESCRIPTION OF THE CURRENT EMBODIMENT
[0039] An embodiment of the firearm control mechanism of the present invention is shown and generally designated by the reference numeral 200.
[0040] FIG. 2 illustrates the improved firearm control mechanism 200 of the present invention. More particularly, the firearm control mechanism is shown installed in a rifle 300 adjacent to the trigger guard 302 and forward of the trigger 304. The trigger is connected to a frame 310 of the rifle and is movable with respect to the frame. The firearm control mechanism has a selector assembly 248 that is rotationally connected to the frame and pivotable with respect to the frame about a pivot axis 250. The selector assembly has a protruding right selector lever 202 to enable the user to rotate a selector shaft 204 (shown in FIGS. 3-11D) into a selected position to place the rifle in a desired mode of operation. Several different firing modes can be available depending on the characteristics of the rifle, including, but not limited to, safe, semi-automatic, multiple round burst, binary, and fully automatic. There may be a corresponding left selector lever 252 on the opposite side of the rifle (shown in FIG. 3) to facilitate ambidextrous operation of the rifle.
[0041] FIG. 3 illustrates the improved firearm control mechanism 200 of the present invention. More particularly, the firearm control mechanism has a selector assembly 248 that includes a selector shaft 204 having a left side 206 and a right side 208. A right selector lever 202 is connected to the right side of the selector shaft by a right selector screw 254. A left selector lever 252 is connected to the left side of the selector shaft by a left selector screw 256. A right selector label 258 and a left selector label 260 show the firing mode of the rifle 300 selected by the current position of the right and left selector levers and selector shaft. The selector assembly interacts with additional components installed in the frame 310 of the rifle 300 to form the fire control mechanism that determines the mode of operation of the rifle 300 based on the position of the selector assembly when the trigger 304 is pulled. The additional components include the trigger that is rotatably mounted on a trigger pin 330 and spring-biased into a forward position by a trigger spring 312 acting on a trigger spring plunger 314 that contacts the trigger. The additional components also include a disconnector 316 that is spring-biased in an upward direction by a disconnector spring 318, an intermittent disconnector spacer 320 receiving an intermittent disconnector spacer spring 322 and an intermittent disconnector spacer guide rod 324, a hammer 306 that is spring-biased into a forward position by a hammer spring 326 and rotatably mounted on hammer spacers 328 and a hammer pin 332. A fire control housing receives a magazine latch pivot 336 and an ejector pin 338 and is spring biased by a bolt catch pin 340.
[0042] FIGS. 4-6 illustrate the improved selector shaft 204, detent 234, and spring 240 of the present invention. More particularly, the selector shaft has a left side 206 and a right side 208. The left and right sides are enlarged relative to the selector shaft and are adapted for attachment of right selector lever 202 and left selector lever 252. An intermediate portion of the selector shaft defines a selector 210. The selector 210 is a planar body having a square lower portion 212 and a rounded upper portion 214. The rounded upper portion has protruding ends 216, 218 that overhang the square lower portion and form right angles 220, 222. The square lower portion has three sides 224, 226, 228 that are each separated by an angled corner 230, 232. The fourth side of the square lower portion forms the rounded upper portion.
[0043] The spring-loaded detent 234 is a cylindrical body having a flat top 236 and a bottom 238. The spring 240 presses against the bottom and pushes the flat top against the selector 210. The elements shown in FIG. 4 in dashed lines are the trigger 304 pivotally mounted on trigger pin 330 and the disconnector 316 and intermittent disconnector spacer 320 mounted on the trigger pin 330 and intermittent disconnector spacer guide rod 324. These components determine the mode of operation of the rifle 300 based on the position of the selector shaft 204 when the trigger 304 is pulled. FIG. 5 includes the hammer 306.
[0044] FIGS. 7A-D illustrate the improved firearm control mechanism 200 of the present invention. More particularly, the firearm control mechanism is shown rotating counterclockwise 90° to transition the rifle 300 from a first mode of operation to a second mode of operation. In FIG. 7A, the rifle is shown in a first mode of operation. The spring 240 is received in a bore 308 in the rifle and a bore 242 defined by the bottom 238 of the spring-loaded detent 234. The spring urges the flat top 236 against the side 224 of the square lower portion 212 of the selector 210. The selector cannot be rotated further clockwise because of interference created by the protruding end 218 of the rounded upper portion 214. The selector cannot be rotated counterclockwise unless sufficient pressure is exerted to compress the spring and shift the spring-loaded detent out of the way. In FIG. 7B, sufficient pressure has been exerted to compress the spring and shift the spring-loaded detent out of the way such that the selector has rotated counterclockwise relative to the position shown in FIG. 7A so a forward portion 244 of the flat top of the spring-loaded detent is urged against the angled corner 230 of the selector. In FIG. 7C, sufficient pressure has been exerted to compress the spring and shift the spring-loaded detent out of the way such that the selector has rotated further counterclockwise relative to the position shown in FIG. 7B so a rearward portion 246 of the flat top of the spring-loaded detent is urged against the angled corner 230 of the selector. In FIG. 7D, sufficient pressure has been exerted to compress the spring and shift the spring-loaded detent out of the way such that the selector has rotated further counterclockwise relative to the position shown in FIG. 7B so the flat top of the spring-loaded detent is urged against the side 226 of the selector.
[0045] In the position shown in FIG. 7D, the selector 210 has rotated 90° counterclockwise relative to the position shown in FIG. 7A, thereby transitioning the rifle 300 from a first mode of operation to a second mode of operation. The selector cannot be rotated clockwise or counterclockwise unless sufficient pressure is exerted to compress the spring and shift the spring-loaded detent out of the way. The user has the option to rotate the selector further counterclockwise by 90° to transition the rifle from the second mode of operation to a third mode of operation, at which point the flat top 236 is urged against the side 228 of the selector, and further counterclockwise rotation of interference created by the protruding end 216 of the rounded upper portion 214. The user also has the option to rotate the selector clockwise by 90° to return the rifle to the first mode of operation.
[0046] The current invention includes at least the rotational selector 210, at least one linearly translating spring-loaded detent 234, and at least one spring 240 capable of imparting axial load onto the spring-loaded detent. The invention may also include one or more selector levers 202, 252 attached to the selector via the selector shaft 204, any receivers or frames 310 or structures that locate the selector and allow the selector to rotate about a pivot axis 250, any receivers or frames or structures that locate the spring-loaded detent and allow the spring-loaded detent to translate normal to or at an angle to the selector, any receivers or frames or structures that locate the spring such that the spring is able to impart a linear force onto the spring-loaded detent, and any other pieces connected to or rotating with the selector (such as a multi-piece selector).
[0047] The flat top 236 of the spring-loaded detent 234 is shaped such that the surface that contacts the sides 224, 226, 228 of the selector 210 is normal to the axial line of motion of the spring-loaded detent. There is also a corresponding surface or series of surfaces on the sides of the selector. These surfaces on the sides of the selector are parallel to a theoretical tangential plane on the selector's radius of rotation (Rn). The surfaces on the sides of the selector are offset by some distance (Rf) such that rotating the selector rotates the surfaces on the sides of the selector and causes the spring-loaded detent to translate along its axial axis by a distance Rd=Rf*(sec(Θ)−1) where Rd is the displacement distance of the spring-loaded detent, Rf is the distance from the centerline of rotation to a selected surface on a side of the selector, and Θ is the angle from the normal vector of the a selected surface on a side of the selector to the edge of the selected surface on a side of the selector and is generally smaller than 90°. This allows the spring-loaded detent to constrain the angle of the selector by imparting a normal force from the spring-loaded detent surface to the selected surface on a side of the selector, which generally travels through the centerline of the selector. The translational displacement of the spring-loaded detent when the selector is rotated will provide resistance until the selector is rotated greater than 0 and will aid in the rotation of the selector until it is normal to another selected surface on a side of the selector.
[0048] The selector 210 can be made from a variety of materials including metals (steel, aluminum, titanium, etc.), polymers, plastics, composites, and/or ceramics. The selector can be manufactured by machining, turning, casting, injection-molding, forming, or abrasive cutting. The spring-loaded detent can be made out of a variety of materials, including metals, polymers, plastics, composites, and/or ceramics, and is generally round, but can also be any other shape capable of translating axially while being constrained laterally. The spring-loaded detent can be manufactured by machining, turning, casting, injection-molding, forming, or extruding. The spring-loaded detent may also have a feature such as a slot or shelf that limits its axial translation but still allows the selector detent surface to contact the selected surface on a side of the selector.
[0049] The current invention's interface between the selector 210 and the spring-loaded detent 234 is different from other common selector-selector detent interfaces for a variety of reasons. It allows the selector to be biased towards the position it is angularly closest to, with the amount of bias depending on how large the selected surface on a side of the selector is and the angle between the sides of the selector. It also greatly improves manufacturability, replacing conical or hemispherical notches and V-shaped grooves with simple flat surfaces that are more easily manufactured and inspected. In some applications, this design can even aid in installation if the installer needs to depress the spring-loaded detent against the spring 240 using a punch.
[0050] FIGS. 8-10 illustrate the improved firearm control mechanism 200 of the present invention. More particularly, the selector assembly for firearms is shown with the selector shaft 204 in the safe position. With the selector shaft in this position, the trigger camming surface 262 blocks clockwise rotation of the trigger 304, thereby preventing the trigger from being pulled to discharge the rifle 300.
[0051] FIGS. 11-11D illustrate the improved selector shaft 204 of the present invention. More particularly, enlarged sectional views of the trigger camming surface 262, selector 210, and intermittent disconnector spacer camming surface 264 are provided so the details of their surface profiles can be fully appreciated. The trigger camming surface is a first cam surface of the selector shaft 204 operably engaged to a follower portion of the trigger 304. The selector has a detent portion (square lower portion 212) of the selector shaft having a detent surface (sides 224, 226, 228 of the selector) opposing a spring-biased detent follower (detent 234) connected to the frame 310 and operable to reciprocate against the detent surface. The detent surface has a plurality of stable positions (sides 224, 226, 228 of the selector), each corresponding to an operating condition of the fire control mechanism 200. The detent portion lacks any concave surfaces in the current embodiment. The detent surface has a plurality of flat cam surfaces (sides 224, 226, 228 of the selector), at least two of which are perpendicular to each other. A corner (angled corners 230, 232) joins the plurality of flat cam surfaces. The detent follower has a flat face (flat top 236) contacting the detent surface. The detent surface includes a plate having peripheral edges (square lower portion 212) facing away from the pivot axis 250. The detent surface is spaced apart from the first cam surface. The intermittent disconnector spacer camming surface 264 is a second cam surface of the selector shaft. The detent surface is between the first cam surface and the second cam surface. The detent portion has only flat and convex surface portions. The detent portion is a planar body perpendicular to the pivot axis. The detent surface is a peripheral surface of the detent portion. At least a portion of the detent surface extends radially from the pivot axis by a greater amount than angularly corresponding portion of the first cam surface. The detent portion lacks any recesses.
[0052] In the context of the specification, the terms “rear” and “rearward,” and “front” and “forward” have the following definitions: “rear” or “rearward” means in the direction away from the muzzle of the firearm while “front” or “forward” means it is in the direction towards the muzzle of the firearm.
[0053] While a current embodiment of a firearm control mechanism has been described in detail, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
[0054] Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
