U.S. patent application number 12/334880 was filed with the patent office on 2009-05-14 for self-powered impulse averaging recoil operated machine gun with a rotary lock bolt driven by bimodal cams.
This patent application is currently assigned to General Dynamics Armament and Technical Products. Invention is credited to Davkd L. Steimke, Parke R. Warner.
Application Number | 20090120276 12/334880 |
Document ID | / |
Family ID | 39682244 |
Filed Date | 2009-05-14 |
United States Patent
Application |
20090120276 |
Kind Code |
A1 |
Steimke; Davkd L. ; et
al. |
May 14, 2009 |
Self-Powered Impulse Averaging Recoil Operated Machine Gun With A
Rotary Lock Bolt Driven By Bimodal Cams
Abstract
A weapon system comprising a receiver, a barrel, a bolt, a
barrel extension, a bolt carriage, and a toggle assembly. The
barrel may have a longitudinal axis. The bolt may be spaced a
distance from a rearward end of the barrel along the longitudinal
axis of the barrel. The barrel extension may be attached to the
bolt and connecting the barrel with the bolt. The barrel extension
and bolt may be adapted to move linearly with respect to the
receiver in a direction parallel to the longitudinal axis of the
barrel. The bolt carriage may be movable relative to the bolt
between an ammunition loading position and a firing position. The
toggle assembly may be adapted to drive the bolt carriage between
the loading position and the firing position in response to
movement of the barrel extension and bolt relative to the
receiver.
Inventors: |
Steimke; Davkd L.;
(Burlington, VT) ; Warner; Parke R.; (Burlington,
VT) |
Correspondence
Address: |
HUNTON & WILLIAMS LLP;INTELLECTUAL PROPERTY DEPARTMENT
1900 K STREET, N.W., SUITE 1200
WASHINGTON
DC
20006-1109
US
|
Assignee: |
General Dynamics Armament and
Technical Products
|
Family ID: |
39682244 |
Appl. No.: |
12/334880 |
Filed: |
December 15, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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11531340 |
Sep 13, 2006 |
|
|
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12334880 |
|
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|
|
60821310 |
Aug 3, 2006 |
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Current U.S.
Class: |
89/132 |
Current CPC
Class: |
F41A 3/26 20130101; F41A
5/08 20130101 |
Class at
Publication: |
89/132 |
International
Class: |
F41A 19/06 20060101
F41A019/06 |
Goverment Interests
GOVERNMENT LICENSE RIGHTS
[0002] The U.S. Government has a paid-up license in this invention
and the right in limited circumstances to require the patent owner
to license others on reasonable terms as provided for by the terms
of W15QKN-04-C-1093 awarded by the Department of Defense.
Claims
1. A weapon system comprising: a receiver; a barrel having a
longitudinal axis; a bolt spaced a distance from a rearward end of
the barrel along the longitudinal axis of the barrel; a barrel
extension attached to the bolt and connecting the barrel with the
bolt, the barrel extension and bolt adapted to move linearly with
respect to the receiver in a direction parallel to the longitudinal
axis of the barrel; a bolt carriage movable relative to the bolt
between an ammunition loading position and a firing position; and a
toggle assembly adapted to drive the bolt carriage between the
loading position and the firing position in response to movement of
the barrel extension and bolt relative to the receiver.
2. The weapon system of claim 1, wherein the bolt is spaced a fixed
distance from a rearward end of the barrel.
3. The weapon system of claim 2, wherein and the barrel is adapted
to move relative to the receiver in conjunction with the bolt and
barrel extension.
4. The weapon system of claim 1, wherein the bolt assembly moves
linearly relative to the bolt in a direction parallel to the
longitudinal axis of the barrel.
5. The weapon system of claim 4, wherein when the bolt assembly is
in the firing position, the bolt assembly overrides the space
between bolt and the rearward end of the barrel, capturing a round
of ammunition in the space between the bolt and the rearward end of
the barrel.
6. The weapon system of claim 4, wherein when the bolt assembly is
in the ammunition loading position, the bolt assembly overrides at
least a portion of the bolt, opening the space between the bolt and
the rearward end of the barrel.
7. The weapon system of claim 6 further comprising a load pawl and
a load pawl cam surface that drives the load pawl through a range
of movement in response to movement of the bolt and barrel
extension.
8. The weapon system of claim 7 wherein the movement of the load
pawl includes lifting a round of ammunition into the space between
the bolt and the rearward end of the barrel as the bolt assembly
moves from the ammunition loading position to the firing
position.
9. The weapon system of claim 7 wherein the movement of the load
pawl includes sweeping the opening between the bolt and the
rearward end of the barrel to remove a spent ammunition cartridge
as the bolt assembly moves from the firing position to the
ammunition loading position.
10. The weapon system of claim 1, wherein the toggle comprises a
cam follower, and the firearm further comprises a cam surface for
guiding movement of the cam follower.
11. The weapon system of claim 10, wherein the cam surface is
attached to an interior surface of the receiver.
12. The weapon system of claim 10, wherein the cam surface is
integrally formed with an interior surface of the receiver.
13. The weapon system of claim 1, wherein the toggle comprises a
forward toggle and a rearward toggle.
14. A recoil operated firearm comprising: a barrel having a
longitudinal bore axis; a bolt being collinear with the bore axis;
a bolt assembly comprising a ammunition-holding cavity formed
therethrough, the ammunition-holding cavity having a longitudinal
axis collinear with the bore axis; the bolt assembly being adapted
for linear movement between a charged position and a firing
position, wherein the linear bolt assembly movement is relative to
the barrel and collinear with the bore axis, wherein, when in the
bolt assembly charged position: the bolt assembly is positioned
rearward end of the barrel, the forward end of the bolt assembly is
spaced a distance away from the rearward end of the barrel, and the
bolt assembly overrides at least a portion of the bolt such that
the bolt occupies at least a portion of the ammunition-holding
cavity; and wherein, when in the bolt assembly firing position: a
forward surface of the bolt assembly sealingly contacts a rearward
surface of the barrel, and a forward end of the bolt sealingly
contacts a rearward end of the bolt assembly.
15. The firearm of claim 14 wherein, when in the bolt assembly
charged position, a forward surface of the bolt is generally
coplanar with a forward surface of the bolt assembly.
16. The firearm of claim 14 further comprising a barrel extension,
wherein the barrel is removably attached to the barrel
extension.
17. The firearm of claim 16 further comprising a receiver, wherein:
the receiver at least partially houses the barrel extension, the
barrel extension being adapted for linear movement relative to the
receiver between a charged position and a firing position
18. The firearm of claim 17 wherein, the receiver further comprises
one or more barrel extension rails to guide movement of the barrel
extension relative the receiver.
19. The firearm of claim 17 further comprising a toggle
assembly.
20. The firearm of claim 19 wherein, the toggle assembly comprises:
a first toggle arm; and a second toggle arm; wherein the first
toggle arm is pivotally connected to the bolt assembly, the second
toggle arm is pivotally connected to the barrel extension; and the
first toggle arm is pivotally connected to the second toggle arm.
Description
[0001] This application is a continuation of, claims priority to,
and incorporates by reference in its entirety, the following U.S.
patent application Ser. No. 11/531,340, entitled "SELF-POWERED
IMPULSE AVERAGING RECOIL OPERATED MACHINE GUN WITH A ROTARY LOCK
BOLT DRIVEN BY BIMODAL CAMS" filed Sep. 13, 2006, which claims
priority from U.S. provisional patent application Ser. No.
60/821,310, filed on Aug. 3, 2006, which is incorporated herein by
reference in its entirety.
FIELD OF THE INVENTION
[0003] Embodiments of the invention relate to an automatic weapon.
More specifically, embodiments of the invention relate to a recoil
operated automatic weapon with a rotary lock bolt.
BACKGROUND OF THE INVENTION
[0004] Throughout history, military forces have been employed in
offensive, defensive, and peace-keeping roles. In all roles, these
military forces have required the use of weapons, and more
particularly, firearm weapons. The present invention is directed to
a machine gun with a rotary lock bolt driven by bimodal cams.
SUMMARY OF THE INVENTION
[0005] One aspect of the present invention provides a weapon system
comprising a receiver having at least one side plate with a bimodal
cam way formed therein. The bimodal cam has an upper surface and a
lower surface. A barrel extension is provided with at least a first
end and at least one side plate with a cam way formed into the at
least one side. A barrel is provided with a longitudinal axis and
mounted to the barrel extension first end. A spring and buffer
assembly is provided with a first end and a second end, wherein the
first end is mounted to the barrel extension and the second end is
mounted to the receiver. The mounted spring and buffer assembly are
generally parallel to the barrel longitudinal axis. A bolt carriage
is provided with a first end, a second end and at least one side
plate, and a carriage cam way formed in the side plate. The weapon
system further comprises a firing pin assembly fixed to the bolt
carriage and having a bolt cam way. A rotary lock bolt having a
first end, a second end, and a hollow pass-through is provided with
the first end comprises a generally flat forward facing surface and
a plurality of lugs radially arranged about the forward facing
surface. The hollow pass-through extends through both first and
second ends, and is shaped to telescopically receive the firing pin
assembly. A bolt cam pin is adapted to be fixedly attached to the
rotary lock bolt and simultaneously capable of sliding in and along
the firing pin assembly bolt cam way. The relative movement of the
bolt cam pin is relative movement along the longitudinal axis
between the firing pin assembly and the rotary lock bolt causes the
rotary lock bolt to rotate about the longitudinal axis due to the
bolt cam pin riding in the bolt cam way. A toggle assembly having a
toggle arm, a carriage cam way roller that rides in the carriage
cam way, a barrel extension cam way roller that rides in the barrel
extension cam way, and a receiver bimodal cam way roller to ride in
the receiver bimodal cam way, the carriage cam way roller, barrel
extension cam way roller and receiver cam way roller being
collinear. The receiver roller rides on at least a portion of the
bimodal cam way upper surface during a forward stroke of a firing
cycle of the weapon system, and the receiver roller rides on at
least a portion of the bimodal cam way lower surface during a
rearward recoil stroke of a firing cycle of the weapon system.
BRIEF DESCRIPTION OF THE FIGURES
[0006] The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and, together with the description, serve to explain
the principles of the invention.
[0007] FIG. 1A is a preferred embodiment of the present invention
shown in a perspective view from the right and rear of the
invention.
[0008] FIG. 1B is a preferred embodiment of the present invention
shown in a perspective view from the left and rear of the
invention.
[0009] FIG. 2 is a perspective view the receiver of the present
invention.
[0010] FIG. 3 illustrates a side view of the bimodal cam of the
present invention.
[0011] FIG. 4 depicts the operating group of the present
invention.
[0012] FIG. 5 is a perspective view of the barrel extension of the
present invention.
[0013] FIG. 6 is a perspective view of the rotary lock bolt
assembly of the present invention.
[0014] FIG. 7A illustrates the rotary lock bolt of the present
invention.
[0015] FIG. 7B shows the components used in conjunction with the
rotary lock bolt of the present invention.
[0016] FIG. 7C depicts the round extractor of the present
invention.
[0017] FIG. 7D is a side view of the round retainer of the present
invention.
[0018] FIG. 7E illustrates the round ejector of the present
invention.
[0019] FIG. 7F illustrates the round rammer of the present
invention.
[0020] FIG. 8A illustrates the firing pin assembly of the present
invention.
[0021] FIG. 8B shows the extraction buffer of the present
invention.
[0022] FIG. 8C depicts the cam pin and cam pin retainer of the
present invention.
[0023] FIG. 8D illustrates the firing pin of the present
invention.
[0024] FIG. 9A depicts the rotary lock bolt assembly installed in
the carriage.
[0025] FIG. 9B depicts the toggle assembly.
[0026] FIG. 10A is a top view of the operating group in the sear
position.
[0027] FIG. 10B is a cross-sectional view of the present invention
showing the position of the rollers in the sear position.
[0028] FIG. 11A is a top view of the operating group at the start
of the firing cycle.
[0029] FIG. 11B is a cross-sectional view of the present invention
showing the position of the rollers at the start of the firing
cycle.
[0030] FIG. 12A is a top view of the operating group at a position
of the firing cycle.
[0031] FIG. 12B is a cross-sectional view of the present invention
showing the position of the rollers at a position of the firing
cycle.
[0032] FIG. 12C is a cross-sectional view showing the bolt assembly
stripping the round from the link with the rammer.
[0033] FIG. 13A is a top view of the operating group closing the
chamber.
[0034] FIG. 13B is a cross-sectional view of the present invention
showing the position of the rollers when the chamber is closed.
[0035] FIG. 14A is a top view of the operating group with the
firing pin contacting the round.
[0036] FIG. 14B is a cross-sectional view showing the position of
the rollers when the firing pin contacts the round.
[0037] FIG. 15A is a top view of the operating group at the start
of recoil.
[0038] FIG. 15B is a cross-sectional view showing the position of
rollers at the start of recoil.
[0039] FIG. 16A is a top view of the operating group ejecting a
spent cartridge.
[0040] FIG. 16B is a cross-sectional view showing the position of
the rollers when a spent cartridge is ejected.
[0041] FIG. 16C is a cross-sectional view showing the bolt assembly
ejecting the round after firing.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042] The following description is intended to convey a thorough
understanding of the invention by providing a number of specific
embodiments and details involving an automatic weapon system 100.
It is understood, however, that the invention is not limited to
these specific embodiments and details, which are exemplary only.
It is further understood that one possessing ordinary skill in the
art, in light of known systems and methods, would appreciate the
use of the invention for its intended purposes and benefits in any
number of alternative embodiments. Throughout the specification,
the use of the terms "front" or "forward" refer to or toward the
weapon system muzzle, and the terms "rear" or "rearward" refer to
or toward the end of the weapon system 100 opposite the muzzle.
[0043] Referring to FIGS. 1A and 1B, a recoil operated gun system
100 is provided as an exemplary embodiment of the invention. The
gun system 100 of the preferred embodiment comprises a receiver 200
and an operating group 300. The gun system 100 comprises a feeder
102, a cartridge guide 104, an eject port 106, and a trigger 108.
These components are generally known in the art.
[0044] Referring now to FIGS. 2 and 3, the receiver 200 is adapted
to at least partially house the internal operating group 300 (see
FIGS. 1A, 1B, and 4). The receiver 200 comprises a longitudinal
generally U-shaped cradle 202 having a horizontal member and two
parallel vertical sidewalls. The cradle 202 is a mounting platform
for parallel left 204 and right 206 side plates. The two side
plates 204, 206 are mounted on the vertical sidewalls of the cradle
202. The cradle 202 further provides a mounting surface for a left
cartridge guide mount 208 on the left side of the weapon 100, and a
sector gear 210. The sector gear 210 interfaces with a pintle (not
shown) to allow for precise control over the elevation or
depression of the weapon system, such sector gears are generally
known in the art.
[0045] A bimodal cam way 212 is formed in each side plate 204, 206.
The two bimodal cam ways 212 are parallel to each other. Each side
plate 204, 206 further comprise barrel extension rails 214 to guide
the movement of the barrel extension 302 and toggles of the
operating group 300, these features are discussed in greater detail
herein. The side plates 204, 206 also comprise mounting surfaces
for a forward feeder mount 216 for mounting the ammunition feeder
102. The left side plate 204 supports an active firing cam 220, and
the right side plate supports a right cartridge guide mount 218.
The active firing cam 220 is spring-loaded and biases the receiver
rollers 382 to the upper surface of the bimodal cam way 212. The
left and right cartridge guide mounts 208, 218 provide a platform
to mount the cartridge guide 104 (see FIGS. 1A-1B). Together, the
side plates 204, 206 comprise mounting surfaces for left 222 and
right 224 sear mounting plates for mounting a sear 226, and
mounting surfaces for mounting a rear side plate support 228. Both
the sear 226 and rear side plate support 228 are mounted transverse
to the longitudinal axis of the cradle 202. The right sear mounting
plate 224 also supports the trigger 108 and trigger axial (not
shown) which extends transversely across to the left 222 sear
mounting through holes in plate.
[0046] Referring to FIG. 3, the bimodal cam way 212 can generally
be described as having an upper flat portion, a sloped portion, and
a lower portion. An active cam gate 213 is attached to the receiver
below the lower portion of the bimodal cam 212. The cam gate 213 is
spring loaded to be biased toward the top of the slots in the cam
plates. The cam way 212 further has upper and lower surfaces. The
function and use of the cam way 212 and its sections are discussed
herein with respect to the weapon system operating cycle.
[0047] With reference to FIG. 4, the operating group 300 comprises
a barrel extension 302, a barrel 304, a chamber 305, a bolt
assembly 306, a toggle assembly 308, a detachable feed post 309, an
impulse averaging buffer assembly 400, and a barrel lock 311.
Referring now to FIG. 5, the barrel extension 302 comprises two
forward 312 (one not shown) and two rear 314 bearings to guide the
barrel extension 302 along the length of the side plates 204, 206,
a forward barrel opening 316, toggle track openings 318 on either
side, barrel extension cam ways 320 on either side, carriage
extractor slots 321, an ejector post slot 322, a carriage rail 323,
an eject window 324, and a buffer mount 325. The barrel 304 is
preferably manufactured from Cr-Mo steel with a chromium-plated
bore. However, the barrel 304 could be manufactured of other
materials known in the art. The barrel 304 is also preferably 0.50
caliber and has a twist ratio of 1 turn per 9 inches of barrel
length. The barrel may also be provided with a quick release
feature, such as by rotating the barrel lock counter-clockwise
until the lock clears the barrel then pull the barrel forward
through the barrel extension opening.
[0048] Referring now to FIGS. 6-9, the bolt assembly 306 comprises
a carriage 326 with 4 bearings 328 and a cam way 330, a rotary lock
bolt 332 with a rammer 334, rammer spring 335, a round extractor
336, a round retainer spring (not shown), an ejector 338 in the
bolt 332, and an ejector spring 340 and a fixed firing pin assembly
342.
[0049] Referring now to FIGS. 7A-7F, the rotary lock bolt 332 has a
generally cylindrical body with a face on a forward surface. The
face of the bolt 332 closes the rear of the chamber 305 during
firing of the weapon system 100. A hollow cylinder runs the length
of the bolt 332 to telescopically receive the firing pin assembly
342. The cylinder extends the entire length of the bolt 332 to
allow the firing pin 343 to extend forward of the bolt head 331 and
into the chamber 305 to impact the primer during firing of the
weapon system 100.
[0050] The round ejector 338 lies generally parallel with the axis
of the barrel 304 and comprises a body 350, a longitudinal finger
352, and an ejector stop post 354. The ejector finger 352 extends
through and beyond the face of the bolt 332. The ejector stop post
354 is formed at the base of the finger 352, and the ejector body
350 is formed rearward of the post 354. The body 350 is elongated
and generally flat, it rides in a groove along the left
circumferential side of the bolt 332. The ejector spring 340 is
circumferentially arranged about the finger 352 and is compressed
between the bolt and the stop post 354, biasing the finger 352
rearward keeping the finger clear of the forward surface of the
bolt head 331.
[0051] The round rammer 334 is mounted in a groove formed in the
top circumferential side of the bolt 332. A pin (not shown) extends
through an opening 333 in the bolt 332 and through the rammer pivot
356. The rammer 334 is mounted to the bolt 332 so as to pivot about
an axis that is perpendicular to the bolt axis and along a vertical
plane. The rammer torsion spring 335 biases the rammer 334 in an
up-pivoting position.
[0052] The round extractor 336 comprises a claw-like edge 357, a
pivot 360, and a hole 362. The round extractor 336 is mounted in a
groove formed in the face of the bolt 332. A pin (not shown)
extends through an opening 337 in the bolt 332 and through the
extractor pivot 360. The extractor 336 is mounted to the bolt 332
so as to pivot about an axis that is perpendicular to the bolt
axis. A compression retainer spring (not shown) biases the
extractor 336 so that it pivots in toward the bolt face 329. The
claw-like edge 357 facilitates gripping a cartridge 110 when it
pivots into the bolt face 329. The pivot 360 is inboard of the
claw-like edge 357 thereby providing a moment about the pivot 360
to close the claw-like edge 357 against the round 110 if it pulls
away from the bolt face 329. The face of the claw-like edge 357 has
an angled surface 359 thereby allowing the round extractor 336 to
be forced open when a round 110 is pushed toward the bolt face 329,
allowing the round 110 into the bolt face 329.
[0053] With reference now to FIGS. 8A-8D, the firing pin assembly
342 comprises a firing pin 343, a bolt cam pin 344, a cam pin
retainer 346, and an extraction buffer 348. The firing pin 343
extends from a forward surface of a firing pin body 366. The firing
pin body 366 comprises a hollow cylinder with two helix bolt cams
368 in which the bolt cam pin 344 rides and a cylindrical rear
opening 367. The bolt cams 368 are openings in the circumferential
surface of the firing pin body 366 with a width slightly wider than
the circumference of the bolt cam pin 344. The forward end of the
cams 368 generally follow helical path generally 30.degree.
relative to a longitudinal axis of the firing pin body 366. The
rearward end of the cams 368, however are generally parallel to the
same longitudinal axis. The firing pin body 366 comprises torsion
restraining lugs 370. The firing pin body 366 further comprises
threads at the rearward end of the opening 367 to threadedly secure
the cam pin retainer 346.
[0054] The cam pin retainer 346 comprises a cylindrical body 349
with lug 351 attached at the rear. A cam pin retainer shaft 347
extends from a forward surface of the cam pin retainer body 349 to
retain the cam pin 344 in the bolt cams 368 by extending into an
opening in the circumferential side of the cam pin 344. The cam pin
344 is free to slide and rotate about the cam pin retainer shaft
347. The cam pin retainer 346 forward end is threadedly received
within the firing pin rear opening 367 so that the shaft 347
extends into the firing pin body 366 and the cam pin 344 is free to
slide through the twisting bolt cams 368. An extraction buffer 348
is retained on the cam pin retainer body 349 between the firing pin
body 366 and the lug 351.
[0055] Referring now to FIGS. 4 and 9, the forward end of the
carriage 326 comprises a bolt opening 364 to telescopically receive
both the firing pin 343 and the bolt 332. The torsion restraining
lugs 370 fit in recesses at the rear end of the carriage 326 to
prevent the firing pin 343 from rotating about the axis of the bolt
332. The bolt 332 is then inserted into the opening 364 and the cam
pin 344 is inserted through the cam pin openings 333 and the bolt
cams 368. The cam pin retainer 346, with the extraction buffer 348
already attached, is then inserted into a retainer opening 372 at
the rear of the carriage 326 and threaded into the firing pin rear
opening 367. The firing pin 343 is now axially fixed to the
carriage 326. The carriage 326 holds the firing pin 343 and bolt
332 collinear. The bolt 332 is now able to slide along the length
of the firing pin 343 and rotate about the firing pin 343,
following the bolt cams 368 through the cam pin 344. The carriage
332 is inserted into the barrel extension 302 through the carriage
extraction slots 321. The barrel extension 302 now retains the
firing pin 343, bolt 332, chamber 305, and barrel 304 collinear.
The bolt cam pin 344 rides in the bolt cams 368 thereby defining
both the rotational and axial position of the bolt 332. A bolt lug
is restrained from rotation by a bolt side rail (not shown) in the
barrel extension 302 thereby retaining the bolt 332 and bolt face
329 forward of the firing pin during the first half of the firing
cycle.
[0056] The toggle assembly 308 comprises left 374 and right 375
toggles, a toggle shaft 376, a carriage roller 378, barrel
extension rollers 380, a receiver roller 382, and rear rollers 384.
The toggle shaft 376 connects the two toggles 374, 375. A rear
roller 384 is positioned between the shaft 376 and each toggle 374,
375 and allows the toggle assembly 308 to ride in the toggle track
openings 318 on the barrel extension 302. The left toggle 374
extends forward and connects to a barrel extension roller 380. The
right toggle 375 extends forward parallel to the left toggle 374.
The right toggle 375 is attached to a collinear stack of rollers,
the carriage roller 378, a barrel extension roller 380, and the
receiver roller 382. The carriage roller 378 rides in the carriage
cam way 330, the barrel extension rollers 380 ride in the barrel
extension cam ways 320, and the receiver roller 382 rides in the
receiver's bimodal cam way 212. Because these rollers are
collinear, the carriage cam way, the barrel extension cam way 320
and the bimodal cam way 212 will always share an intersecting
point. These rollers and cams work together to adjust the position
and speed of the carriage 326 relative to the barrel extension 302
as the barrel extension 302 moves through the receiver 200 during
the operating cycle. An ejector bar 390 is attached to the side of
and is collinear with and free to rotate about the toggle shaft
376. The front of the ejector bar 390 is supported by a groove in
the ejector 338 and the front of the ejector bar 390 rests on the
ejector post 354 pushing the round ejector 338 forward.
[0057] Embodiments of the recoil system are described in U.S. Pat.
No. 6,343,536 which is incorporated herein by reference.
[0058] With reference to FIGS. 10A-17, the cycle of the weapon
system 100 will now be discussed in detail. With the weapon 100 in
a neutral position [?], the operator first charges the weapon 100,
as is known in the art
[0059] Referring to FIGS. 10A-10B, with the weapon 100 is charged
with the barrel extension 302 located at the rear of the receiver
200 where it is held back by a hook on the sear 226 (see FIG. 11B).
The bolt carriage 326 is positioned to the rear of the barrel
extension 302 and held in place by the rollers 378, 380, 382
located at the top of their respective cam ways 330, 320, 212. The
round ejector finger 352 extends forward of the bolt head 331 and
is held in this position by the ejector stop post 354. A cartridge
110 is in the strip position in the cartridge guide 104.
[0060] With reference to FIG. 11, the operator initiates the firing
sequence by carefully aiming the weapon system 100 and pulling the
trigger 108. The trigger 108 moves the sear 226 out of the way,
releasing the barrel extension 302, allowing the buffer main spring
402 to push the barrel extension 302 forward. The receiver roller
382 moves along the upper portion of the bimodal cam way 212. With
the barrel extension 302 0.25 inches from the sear position, the
rammer 334 engages the cartridge 110 and pushes it through a link
(not shown).
[0061] Referring now to FIGS. 12A-12C, the barrel extension 302
continues forward, the receiver roller 382 enters the downward
sloping portions of the bimodal cam way 212, pushing the receiver
roller 382, barrel extension roller 380, and carriage roller 378
through a downward changing slope. Moving through the changing
slope, the barrel extension roller 380 begins to move downward and
decelerate the barrel extension 302. At the same time, the carriage
roller 378 pushes on the carriage cam way 330 to increase the
carriage 326 acceleration relative to that of the barrel extension
302. With the barrel extension 302 2.57 inches from the sear
position, the rammer 334 to begins to push the cartridge 110 into
the barrel chamber 305. At 3.1 inches from the sear position, the
bolt assembly 306 and bolt carriage 326 have traveled farther than
the ejector bar 390. This relieves the ejector stop 354 of the
ejector bar 390 and allows the ejector spring 340 to push the
ejector 338 rearward, clearing the ejector from the bolt face
329.
[0062] With reference now to FIGS. 13A and 13B, the barrel
extension 302 continues forward with enough momentum to drive the
ammunition feeder 102, which indexes the next cartridge into
position. Such feed systems are generally known in the art, such
as, for example, that disclosed by U.S. Pat. No. 6,343,536, which
is incorporated herein by reference. As the barrel extension 302
continues forward, the receiver roller 382 moves through the
relieved portion of the bimodal cam way (see FIG. 13B). The
carriage 326 is slowed down relative to the receiver and barrel
extension and the receiver roller 382 is forced to the upper
surface of the bimodal cam by the active cam gate 213. With the
barrel extension 7.2 inches from the sear position, the bolt head
331 closes the chamber 305 and its forward motion stops. As the
chamber 305 closes, the forward motion of the ammunition round 110
is stopped by the barrel and it is forced into the round extractor
336. The carriage 326 however continues forward relative to the
bolt 332. Moving forward, the carriage 326 pushes the firing pin
forward, which cause the bolt cam pin 344 to move through the bolt
cams 368 forcing the bolt 332 to rotate clockwise.
[0063] Referring now to FIGS. 14A and 14B, the barrel extension 302
continues forward, driving the receiver roller 382 farther through
the bimodal cam 212, accelerating the carriage 326. The firing pin
assembly 342 continues forward, rotating the bolt 332 until it
locks with the chamber 305. With the barrel extension 8.0 inches
from the sear position, the carriage 326 drives the firing pin 343
into the cartridge primer, causing the propulsion train to ignite
and push the bullet out of the barrel 304. At this time, the barrel
extension 302 forward movement is stopped and it is driven rearward
from the impulse of the fired round.
[0064] Referring now to FIGS. 15A-16C, the unlocking of the bolt
will now be explained. Due to the impulse of the fired round, the
barrel extension 302 moves rearward, driving the receiver roller
382 into the lower surface of the bimodal cam 212. The carriage 326
then accelerates rearward by the receiver roller 382 moving through
the upward slope of the bimodal cam 212 (see FIG. 16B). At the same
time, the barrel extension rollers 380 and carriage roller 378 move
upward in their respective cam ways 330, 320. As the carriage 326
moves rearward, the bolt 332 is initially still held in the chamber
305 as the cam pin 344 moves through the straight portion of the
bolt cam 368. When the carriage 326 proceeds farther rearward, the
cam pin 344 enters the helical portion of the bolt cam 368 and the
bolt 332 rotates counterclockwise and is unlocked from the chamber
305 and pulled rearward by the carriage 326.
[0065] With reference to FIGS. 16A-16C, the barrel extension 302
continues rearward driving the rollers 378, 380, 382 upward and
along their respective cam ways 330, 320, 212. The forward
claw-like edge 357 of the round extractor 336 grips the rim of the
cartridge 110 and pulls the cartridge 110 out of the chamber 305.
The receiver roller now enters the upward sloped portion of the
bimodal cam 212 and decelerates the rearward moving carriage 326.
The ejector stop post 354 then engages the ejector stop 354 (See
FIG. 16C) causing the ejector finger 352 to extend forward of the
bolt head 331, impacting the back of the cartridge 110 near its
circumferential edge, pushing the cartridge 110 off the bolt head
331 and out of the grip of the round extractor 336 and rotating the
cartridge 110 laterally clear of the weapon through the eject port
106.
[0066] The barrel extension 302 continues rearward driving the
receiver roller 382 into top portion of the bimodal cam 212 to sear
the carriage 326. The barrel extension 302 continues rearward until
the buffer assembly 400 stops it. The barrel extension 302 will
then sear up or continue forward to repeat the firing cycle,
depending on the operating mode and the orientation of the trigger
108. The sear position is illustrated in FIGS. 10A and 10B.
[0067] While the firing cycle has been described at 7 discrete
points relating to FIGS. 10A-16B, these 7 discrete positions have
been described merely for illustrative purposes only. It should be
understood that, in operation, the present invention's firing cycle
comprises a smooth and continuous sequence of motion, taking the
operating group 300 from sear position, to firing the round, and
back to sear position.
[0068] Other embodiments of the invention will be apparent to those
skilled in the art from consideration of the specification and
practice of the invention disclosed herein. It is intended that the
specification be considered as exemplary only, with a true scope
and spirit of the invention being indicated by the following
claims.
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