U.S. patent application number 15/607545 was filed with the patent office on 2017-09-14 for gas key.
This patent application is currently assigned to D.S. Arms, Incorporated. The applicant listed for this patent is Marc Christenson. Invention is credited to Marc Christenson.
Application Number | 20170261278 15/607545 |
Document ID | / |
Family ID | 50185591 |
Filed Date | 2017-09-14 |
United States Patent
Application |
20170261278 |
Kind Code |
A1 |
Christenson; Marc |
September 14, 2017 |
Gas Key
Abstract
An improved gas key assembly for a fire arm, such as an AR 15 or
a M4 rifle, having a gas key fastened by fasteners on a bolt
carrier assembly where the gas key moves with the bolt carrier when
the fire arm is fired, wherein the gas key has a slot for receiving
a key element in the slot and the key element has a stem which is
seated in the slot and a rail which overlays the fasteners to
removably secure the gas key to the bolt carrier and holds gas key
resisting unintended separation of the gas key from the bolt
carrier. Also the invention includes a method for securing a gas
key to a bolt carrier in such a fire arm.
Inventors: |
Christenson; Marc;
(Glenview, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Christenson; Marc |
Glenview |
IL |
US |
|
|
Assignee: |
D.S. Arms, Incorporated
Lake Barrington
IL
|
Family ID: |
50185591 |
Appl. No.: |
15/607545 |
Filed: |
May 29, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13717335 |
Dec 17, 2012 |
9664467 |
|
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15607545 |
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61576716 |
Dec 16, 2011 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F41A 5/18 20130101 |
International
Class: |
F41A 5/18 20060101
F41A005/18 |
Claims
1. A bolt carrier assembly for a fire arm, said assembly
comprising: a bolt carrier barrel arranged for reciprocal movement
on said fire arm, a gas key adapted to move with said fire arm,
fastener means on said gas key for securing said gas key to said
barrel, a keyway in said gas key, and a key element in said keyway
overlying said fastener means adapted to retain said gas key in
place during movement of said bolt carrier barrel on said fire
arm.
2. The bolt carrier assembly recited in claim 1, wherein said gas
key is seated on one side of said bolt carrier barrel, and said
fastener means is accessible on one side of said gas key remote
from said barrel assembly.
3. The bolt carrier assembly recited in claim 2, wherein said gas
key has recess means on said side for receiving said fastener
means.
4. The bolt carrier assembly recited in claim 3, wherein said
fastener means and said gas key have corresponding structure for
retaining said fastener in said gas key.
5. The bolt carrier assembly recited in claim 1, wherein said
keyway in said gas key has a nitch for receiving said key
element.
6. The bolt carrier assembly recited in claim 5, wherein said
keyway and said key element have corresponding shapes adapted to
seat said key element in said gas key niche.
6. The bolt carrier assembly recited in claim 6, wherein said key
element and said keyway are trapezoidal in shape.
8. The bolt carrier assembly recited in claim 6, wherein said
trapezoidal shape on a side closest to said barrel is wider than on
a side remote from said barrel.
9. The bolt carrier assembly recited in claim 1, wherein said key
element has a stem adapted for seating in said keyway and rail
extending from said stem adapted for seating over said fastener
means.
10. A gas key for a fire arm adapted for reciprocal movement
responsive to firing said fire arm, said gas key comprising,
fastener means on said gas key for securing said gas key to said
fire arm, a keyway in said gas key, and a key element removably
seated in said keyway overlying said fastener means adapted to
secure said gas key in place on said fire arm during movement and
selectively removable from said fire arm.
11. The gas key recited in claim 10, wherein said key element
comprises a stem adapted for securement in said keyway and a rail
extending from said stem adapted to overlay said gas key.
12. The gas key recited in claim 10, wherein said key element stem
and said keyway have corresponding shapes.
13. A method for fastening a gas key to a bolt carrier in a fire
arm comprising the steps of (a) providing a gas key and bolt
carrier for a fire arm; (b) inserting fastener means into said gas
key and said bolt carrier for securing said gas key to said bolt
carrier; (c) cutting a slot into said gas key of a size and shape
to accept a key element; and (d) inserting said key element into
said gas key slot to overlay said fastener means.
14. In the method recited in claim 13, with the additional step of
providing a stem and a rail on said key element.
15. In the method recited in claim 13, with the additional step of
arranging said key element on said gas key in a position where said
stem is seated in said slot and said rail is seated over said
fastener means.
Description
PRIORITY CLAIM
[0001] This application is a divisional and claims priority from
U.S. Utility patent application Ser. No. 13/717,335, filed Dec. 17,
2012, that in turn claims priority from U.S. Provisional
Application No. 61/576,716, filed on Dec. 16, 2011.
BACKGROUND OF THE INVENTION
[0002] At this time, the number one complaint of AR15 and M4 rifle
users is that the gas key separates from the bolt carrier. The
result is that the rifle ceases to fire. The gas key and bolt
carrier, known jointly as the bolt carrier assembly or carrier
assembly, separate because the screws that hold the gas key to the
bolt carrier loosen over time as the rifle is fired. The original
equipment screws are typically hex bolts. The gas key is drilled to
accept two screws through two holes on the top of the gas key. The
gas key is made with concavities so that the heads of the hex bolts
are recessed. When fired, the bolt carrier assembly travels in the
firing chamber ejecting the round and resetting the hammer under
substantial force.
[0003] Many AR15 users undertake staking the gas key. When staking,
the user would buy staking device and would seek to stake the gas
key in mounting recesses to prevent the hex bolts from backing out.
Unfortunately, the forces at work in the fire arm carrier assembly
nonetheless push out the hex bolts,
[0004] The present invention cures the problem of the fasteners
backing out while allowing the bolt carrier and gas key to be taken
apart for maintenance, which is required from time t time.
[0005] Bolt carrier groups are made by numerous manufacturers. Some
manufacturers stake the bolts holding the gas key to the bolt
carrier. Staking a gas key and the bolts pinches the material on
the gas key to the bolts and inhibits the bolts from turning and
backing out. The problem with such staking is that sometimes the
bolts need to be loosened to maintain the gas key or the bolt
carrier or to repair the fire arm.
[0006] Some users have sought to inhibit back out of the gas key
bolts by applying a cement-type material, such as "LOCTITE." Such
cement products are not a solution to the problem because of the
hot gasses liberated in the firing chamber during the firing of the
AR15 or 14 affect the cement material and the bolts still become
loose or there can be other adverse effects. The bolt reciprocates
during firing, and this reciprocating action produces great force
on the gas key, which further complicates retention of the gas key
on the bolt carrier.
SUMMARY OF THE INVENTION
[0007] The solution to the problem is a change in the fastener
configuration that takes into account the functionality of the bolt
carrier assembly, the environment of the firing chamber, and the
stresses on the fasteners. Presently, the gas key is fitted with
two hex bolts separated forward and aft by about two centimeters.
In one embodiment, the two hex bolts used to attach the gas key to
the bolt carrier have been cut to provide each hex bolt with a flat
edge on one side of the hex bolt head parallel to the shaft of the
hex bolt. The gas key is slotted with a keyway transverse to its
longitudinal direction with a channel to expose the flat edge of
each hex holt. The slot is perpendicular to the long dimension of
the gas key. A key element slides snuggly into the keyway slot such
that the long edge of the key element abuts the flat edge of each
fastener. Also, the key element has an elongated section or rail
forward and aft of the slot that extends over at least part of each
hex bolt. The key element is dimensioned so that it will not
interfere with the travel of the gas key when the rifle is fired.
The key element holds the hex bolts by both stopping the flat edge
of the hex bolt from turning and by blocking the path of a
loosening hex bolt. The key element may be removed from the keyway
so that the gas key, bolt carrier, and hex bolts may be replaced or
maintained.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0008] The preferred embodiment of the invention requires a Gas Key
to be fabricated that has a keyway Channel cut into the Gas Key to
receive the key element, which may be in the shape of a Dovetail.
In the preferred embodiment, the key element is somewhat "T" shaped
with a Stem vertical member and a Rail horizontal member. The Stem
is trapezoidal in shape. The keyway Channel is made to receive
snuggly the key element. In the preferred embodiment, the bottom
edges of the keyway Channel are wide enough that they open into
Fore Hex Bolt Receiving Hole and the Aft Hex Bolt Receiving hole.
In the preferred embodiment, each Hex Bolt would be tightened so
that a flat edge of the Hex bolt would run parallel and in line
with one of the edges of the keyway Channel. When the key element
is set in place, an edge of the Stem of the key element presses
against a flat edge of a Hex Bolt, thereby stopping the Hex Bolts
from turning and thereby loosening. Additionally, the Rail of the
key element at least partially covers the Fore Hex Bolt Receiving
Hole and the Aft Hex Bolt Receiving Hole preventing a Hex Bolt from
backing out of its socket. The Rail Top is curved and of a size
that it operates within the standard AR 15/M4 receiver.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a right side view of the bolt carrier
assembly.
[0010] FIG. 2 is a perspective view of part of the bolt carrier
assembly showing a portion of the gas key secured to the bolt
carrier barrel.
[0011] FIG. 3 is a perspective view of the key element embodying
the present invention.
[0012] FIG. 4 is a top view of part of the gas key secured to the
bolt carrier barrel, with the key element partially set in the
keyway channel and with the rail of the key element partially
covering the hex bolt fasteners.
[0013] FIG. 5 is an enlarged perspective view of part of the bolt
carrier barrel without the key element set into place and showing
the keyway channel and the hex bolts.
[0014] FIG. 6 is right side view of part of the bolt carrier barrel
with the key element set in place in the keyway channel.
[0015] FIG. 7 is a right side perspective view of part of the bolt
carrier barrel with the key element set into the keyway channel and
covering the hex bolt fasteners.
[0016] FIG. 8 is a rear perspective view of the gas key partially
overlying the bolt carrier barrel showing the key element entering
the channel to overlay the hex bolt fasteners.
[0017] FIG. 9 is a left side view of the bolt carrier assembly
showing the gas key secured to the bolt carrier barrel and the key
element set in the keyway channel on the gas key.
[0018] FIG. 10 is a top view of the bolt carrier assembly with the
gas key secured to the bolt carrier barrel.
[0019] FIG. 11 is a bottom plan view of the bolt carrier
assembly.
[0020] FIG. 12 is a front elevation view of the bolt carrier
Assembly with the gas key mounted thereon.
[0021] FIG. 13 is a rear elevation view of the bolt carrier
assembly with the gas key mounted thereon.
[0022] FIG. 14 is a top perspective view of a typical unmounted gas
key.
DETAILED DESCRIPTION OF THE DRAWINGS
[0023] In a bolt carrier assembly 5, the gas key 20 is fastened
using two hex bolts 30 to the bolt carrier barrel 10. The gas key
20 has a fore hex bolt receiving hole 40 and an aft hex bolt
receiving hole 50. Each hex bolt receiving hole 40 and 50,
respectively, is of a diameter and depth so that the head of the
fore hex bolt 70 and the head of the aft hex bolt 80 is completely
recessed into each hex bolt receiving hole 40 and 50, respectively.
The gas key 20 is bolted to the top of the bolt carrier barrel 10
using two hex bolt fasteners 30. The gas key 20 is fabricated with
a keyway channel 60 cut across it in the area between the fore hex
bolt receiving hole 40 and the aft hex bolt receiving hole 50. The
walls of the keyway channel 60 preferably taper outwardly from the
top of the gas key 20 and have a trapezoidal cross-section. In the
preferred embodiment, the keyway channel 60 is wide enough at its
base so that the keyway channel 60 may cut into the fore hex bolt
receiving hole 40 and the aft hex bolt receiving hole 50. In
alternate embodiments, the keyway channel 60 need not cut into
either hex bolt receiving hole and may have a cross-section other
than trapezoidal so long as the key element is well secured in the
gas key, even against substantial forces resulting from the fire
arm firing action. In yet another alternate embodiment, the keyway
channel 60 may cut into only one of the hex bolt receiving
holes.
[0024] To prevent separation or lifting of the gas key 20 from the
bolt carrier barrel 10 due to loosening of the hex bolt fasteners
30, the key element 90 is set snuggly into the keyway channel 60.
The key element 90 may be preferably somewhat "T" shaped and may
comprise of a stem 100 and a rail 110. The stem 100 may have a stem
fore edge 120 and a stem aft edge 130. The rail 110 may comprise a
rail top 140 and a rail bottom 150. In the preferred embodiment,
the stem 100 of the key element 90 is preferably trapezoidal in
shape so that pressure exerted to the rail bottom 150 by one or
both of the fasteners 30 causes the stem fore edge 120 and stem aft
edge 130 to exert pressure on the keyway channel 60 to keep the hex
bolt fasteners 30 from backing out of the fastener receiving holes
40 and 50, thus preventing the gas key 20 from separating from the
bolt carrier barrel 10.
[0025] While the invention has been described and shown in
substantial detail, many modifications and changes can be made in
the structure disclosed without departing from the scope and spirit
of the invention. The invention should not be limited of the exact
structure disclosed.
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