BACKGROUND
Firearm design is progressing towards smaller and lighter designs. A key driver for the overall size and weight of many firearms is the location of the operating system in relation to the bolt carrier. Whether it's direct impingement, short stroke, long stroke, or internal piston, the operating system often features components located above the bolt carrier. In many firearms, the operating system is positioned above the cam pin. Contouring the cam pin can allow for the operating system to be positioned closer to the bolt. A low profile cam pin is needed to avoid contact with a low operating system, reducing the overall height and weight of many modern firearm designs.
SUMMARY OF THE INVENTION
This summary aims to introduce a simplified version of the concepts that are further explained in the Detailed Description. The following text is not intended to identify any key or essential features of the claimed subject matter, nor is the summary designed to determine the scope of the claimed subject matter.
The present invention is a low-profile cam pin compatible with an M4/M16 pattern bolt carrier group, a shortened M4/M16 bolt carrier group, an M110 bolt carrier group, a shortened M110 bolt carrier group, or similar models. The cam pin features a contoured head that allows the operating system components to be positioned closer to the bolt than is possible with existing cam pins, enabling a shorter and lighter overall firearm design.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front top left prospective view of an embodiment of a low profile cam pin, rotating bolt and bolt carrier.
FIG. 2 is a front top right prospective view of an embodiment of a low profile cam pin, rotating bolt, bolt carrier, and low operating rod.
FIG. 3 is a front top right prospective view of an embodiment of a low profile cam pin, rotating bolt, and bolt carrier in the unlocked position.
FIG. 4 is a front top right prospective view of an embodiment of a low profile cam pin, rotating bolt, and bolt carrier in the locked position.
FIG. 5 is a front top right exploded prospective view of an embodiment of a low profile cam pin, rotating bolt, and bolt carrier.
FIG. 6 is a front top right prospective view of an embodiment of a low profile cam pin and a rotating bolt.
FIG. 7 is a front elevation view of an embodiment of a prior art cam pin, rotating bolt, bolt carrier and standard operating rod in the unlocked position.
FIG. 8 is a front elevation view of an embodiment of a prior art cam pin, rotating bolt, bolt carrier and standard operating rod in the locked position.
FIG. 9 is a front elevation view of an embodiment of a prior art cam pin, rotating bolt, bolt carrier and low operating rod in the unlocked position.
FIG. 10 is a front elevation view of an embodiment of a prior art cam pin, rotating bolt, bolt carrier and low operating rod in-between the unlocked and locked position with prior art cam pin making contact with the low operating rod.
FIG. 11 is a front elevation view of an embodiment of a low profile cam pin, rotating bolt, bolt carrier and low operating rod in the unlocked position.
FIG. 12 is a front elevation view of an embodiment of a low profile cam pin, rotating bolt, bolt carrier and low operating rod in the locked position.
FIG. 13 is a front election view of an embodiment of a low profile cam pin, rotating bolt, bolt carrier and low operating rod in the unlocked position.
FIG. 14 is a front elevation view of an embodiment of a low profile cam pin, rotating bolt, bolt carrier and low operating rod in the locked position.
FIG. 15 is a front elevation view of an embodiment of a prior art cam pin.
FIG. 16 is a front top right prospective view of an embodiment of a prior art cam pin.
FIG. 17 is a front elevation view of an embodiment of a low profile cam pin.
FIG. 18 is a front top right prospective view of an embodiment of a low profile cam pin.
FIG. 19 is a front elevation view of an embodiment of a low profile cam pin.
FIG. 20 is a front top right prospective view of an embodiment of a low profile cam pin.
FIG. 21 is a front elevation view of an embodiment of a low profile cam pin, rotating bolt, bolt carrier and low operating rod in the unlocked position with a measuring line from the center of the bolt to the body of the operating rod.
FIG. 22 is a front elevation view of an embodiment of a prior art cam pin with a center line on the firing pin aperture.
FIG. 23 is a front elevation view of an embodiment of a low profile cam pin with a center line on the firing pin aperture.
FIG. 24 is a front elevation view of an embodiment of a low profile cam pin with a center line on the firing pin aperture.
FIG. 25 is a front elevation view of an embodiment of a low profile cam pin, rotating bolt, bolt carrier and low operating rod in the unlocked position with a dotted circle that displays the general cylindrical shape bolt carrier at the low profile cam pin.
DETAILED DESCRIPTION
A few of the preferred embodiments are presented with illustrations and descriptions. Understandably, many modifications could be made without escaping the scope of the invention. Skilled professionals will appreciate the many inventive concepts that qualify as equivalents under the claims. The embodiments described below do not limit the spirit of the invention or the claims.
Not every figure contains every reference number. Terms such as “forward,” “rearward,” “upper,” “lower,” “bottom,” “top,” and “side” are used to refer to the orientations of the invention, as shown in the images. One skilled in the art will be able to determine how these orientational terms may change during the use of the invention.
Two embodiments of the claimed invention are included in the drawings, not to limit the invention's scope but to show how elements and features may be positioned to achieve the same goal of this invention. The prior art cam pin is identified as 10, one embodiment of the low-profile cam pin is identified as 100, and another embodiment of the low-profile cam pin is identified as 200. The embodiments share many characteristics with the prior art. To highlight these similarities, these features will be given the same identification number. Any changes that need to be recognized by the embodiments 100 and 200 will be labeled in the identification number range 100-112 and 200-212, respectively.
FIG. 1 displays an embodiment of a low profile cam pin 100, with a rotating bolt 28 and a shortened M4/M16 type bolt carrier 26. The rotating bolt 28 and low profile cam pin 100 are positioned forward on the cam path 30 and in the unlocked position.
FIG. 2 displays the embodiment from FIG. 1 with the addition of a low profile operating rod 110.
FIG. 3 and FIG. 4 display the embodiment from FIG. 1. FIG. 3 displays a low profile cam pin 100 and a rotating bolt 28 forward on the bolt carrier 26 cam path 30 and in the unlocked position. FIG. 4 displays a low profile cam pin 100 and a rotating bolt 28 rearward in the cam path 30 and in the locked position. The low profile cam pin 100 follows the cam path 30 to rotate the rotating bolt 28 and low profile cam pin 100 in relation to the bolt carrier 26. The low profile cam pin 100 failing to complete its travel in the cam path 30 will cause a failure in the firearm. The bolt must complete its travel in the cam path 30 to successfully lock and unlock to the barrel extension. When successfully unlocked, the bolt carrier may move rearward and forward within the firearm receiver during operation.
FIG. 5 displays an exploded view of the embodiment in FIG. 1.
FIG. 6 displays the relationship between the rotating bolt 28 and a low profile cam pin 100.
FIG. 7 and FIG. 8 Display a front elevation view of a prior art cam pin 10, standard height operating rod 24, rotating bolt 28, and bolt carrier 26. FIG. 7 displays the rotating bolt 28 and the prior art cam pin 10 in the unlocked position. FIG. 8 displays the prior art cam pin 10 and the rotating bolt 28 successfully in the locked position. There is enough clearance between the standard operating rod 24 and the prior art cam pin 10 for the prior art cam pin 10 and rotating bolt 28 to rotate uninterrupted by the standard operating rod 24.
FIG. 9 and FIG. 10 Display the prior art cam pin 10, rotating bolt 28, and bolt carrier 26 from FIG. 9 and FIG. 10 with a low profile operating rod 210. This low profile operating rod 210 is lower on the bolt carrier 26 or closer to the center of the rotating bolt 28 than the standard operating rod 24. FIG. 9 displays the prior art cam pin 10 in the locked position. FIG. 10 displays the prior art cam pin 10 making contact with the low profile operating rod 210 preventing the complete travel of the rotating bolt 28 into the locked position. FIG. 10 displays the area of contact and is marked within a dotted circle.
FIG. 11 and FIG. 12 display the bolt carrier 26, rotating bolt 28, and low profile operating rod 210 of FIG. 9 and FIG. 10 with an embodiment of a low profile cam pin 200. The contoured profile 212 on the head section 14 of the low profile cam pin 200 allows the rotating bolt 28 to rotate successfully between the unlocked and locked position.
FIG. 13 and FIG. 14 displays an embodiment of a low profile cam pin 100 with a low profile operating rod 110 that is lower than the low profile operating rod in the embodiment in FIGS. 9-12. FIG. 13 displays the contoured profile 112 compensating for the low profile operating rod 110 in the unlocked position. FIG. 13 displays the contoured profile 112 allowing the rotating bolt 28 to rotate into the locked position without interference from the low profile operating rod 110.
FIG. 15 and FIG. 16 display a prior art cam pin 10 with a head section 14 and a shaft section 12. Said head section 14 contains a receiver bearing surface 20 that makes contact inside the firearm receiver to prevent the rotating bolt 28 from rotating into the locked position prematurely. The shaft section 12 contains a firing pin aperture 16 allows for a firing pin to pass through the prior art cam pin 10 and a cam path bearing surface 18 that makes contact with the cam path 30 on the bolt carrier 26.
FIGS. 17-20 display embodiments of a low profile cam pin 100 and 200. These embodiments share the shaft section 12, head section 14, firing pin aperture 16, cam path bearing surface 18, and the receiver bearing surface 20 found in FIG. 15 and FIG. 16. However, these embodiments of a low profile cam pin 100 and 200 also contain a contoured profile 112 and 212 that allow proper rotation of a rotating bolt 28 within a bolt carrier 26 with the use of a low profile operating rod 110 and 210 respectively.
FIG. 21 displays an embodiment of a low profile cam pin 200 with rotating bolt 28, bolt carrier 26, and a low profile operating rod 210 with the rotating bolt 28 in the unlocked position. A center line 34 runs from the center of the bolt to the low profile operating rod 210, in an upward parallel direction to the bolt face, perpendicular to the low profile operating rod 210 at the cross section of the low profile cam pin 200. The center line 34 is the distance from the low profile operating rod 210 to the center of the rotting bolt 28 at the low profile cam pin 200. This distance defines a low profile operating rod 210. Low profile operating rod 210 is within 0.6″ from the center of the rotating bolt at the low profile cam pin 200. Low profile operating rod 110 is within 0.59″ from the center of the rotating bolt 28 at the low profile cam in 100. A standard operating rod 24 is has a center line 32 distance greater than 0.6″ from the center of the rotating bolt 28 at the cam pin 10. The dotted lines define the perimeters for a contoured profile 212. The dotted line A1 is the distance from the center of the rotating bolt 28 to the body of the low profile operating rod 210 at the low profile cam pin 200. The dotted line A2 is the same distance as A1 rotated opposite of the rotating bolts rotation, in this embodiment to the A2 is rotated left or counter clockwise. The dotted line B displays the path from the end most point of A1 to A2 rotating counterclockwise from the center of the rotating bolt 28. The the contoured profile 212 of the embodiment of a low profile cam pin 200 exists inside the dotted line B. This insures there is no contact between the low profile operating rod 210 and the low profile cam pin 200 during the rotating bolt 28 rotation in the bolt carrier 26 from the unlocked to the locked position. The Area inside dotted lines A1, A2, and B is the defined clearance area and this defines the contoured profile in this embodiment.
FIG. 22 displays a prior art cam pin 10. The head section 14 of the prior art cam pin 10 exists outside of the dotted line B. This head section 14 outside of B makes contact with the low profile operating rod 210 as illustrated in FIG. 10.
FIG. 23 displays a low profile cam pin 200. The head section 14 of the low profile cam pin 200 contains a contoured profile 212 that reduces the head section of prior art cam pin 10 to remain inside the dotted line B. This contoured profile 212 prevents the low profile cam pin 200 from making contact with the low profile operating rod 210 as illustrated in FIG. 12.
FIG. 24 displays an embodiment of a low profile cam pin 100. The head section 14 of the low profile cam pin 100 contains a contoured profile 112 the reduces the head section to remain inside the dotted line B to the left of the center line 32. This contoured profile 112 prevents the low profile cam pin 100 from making contact with the low profile operating rod 110 illustrated in FIG. 14. In this embodiment the contoured profile 112 also exist to the right of the center line in a con-vexed path marked by the dotted line C to ovoid contact with the low profile operating rod 110 while the bolt is in the unlocked position illustrated in FIG. 13.
FIG. 25 displays an embodiment of a low profile cam pin 200 with rotating bolt 28, bolt carrier 26, and a low profile operating rod 210 with the rotating bolt 28 in the unlocked position. A dotted circle line G displays the general cylindrical shape bolt carrier at the low profile cam pin. Dotted line E is the top of the circular bolt carrier. Dotted line D is the bottom of the low profile operating rod at the cam pin. F is the distance between D and E. In this embodiment F is 0.1″ or less. This can define a low profile operating rod when the bolt carrier group is larger or smaller than a mil-spec diameter. For example a M110 sized bolt carrier group is larger than a M4 sized bolt carrier group, however, both bolt carrier groups are generally circular and operate in a generally circular hole in the receiver.
Those skilled in the art understand the commonality of these parts and appreciate how they interact with the invention compared to common and standard M4/M16 type receivers, M4/M16 type bolt carrier groups, firing pins and their functions.
These embodiments feature a standard operating rod 24, a low profile operating rod 110, and a low profile operating rod 210. These operating rods are placed a different elevations relative to the center of the rotating bolt 28. Although all of the operating rods represented in these embodiments are short stroke recoil spring housings, this does not exclude other operating systems that are positioned above the bolt carrier group. Other operating systems that are encompassed by this invention to be replaced with a low profile operating rod 110 and 210 include but are not limited to DI gas keys found on mill spec M4 bolt carrier groups, short stroke piston rods that impact the bolt carrier group tombstone, guide rod with a recoil spring as the outside diameter, and long stroke pistons or the like positioned low on the bolt carrier 26 requiring the use of a low profile cam pin 100 and 200.
Patent Application
20240288235
