U.S. patent application number 14/541559 was filed with the patent office on 2018-03-29 for bolt capture and release mechanism and method for an imitation machine gun.
This patent application is currently assigned to PATHFINDER SYSTEMS, INC.. The applicant listed for this patent is Pathfinder Systems, Inc.. Invention is credited to C. Ross Cohlmia, Kyle Lowrance.
Application Number | 20180087864 14/541559 |
Document ID | / |
Family ID | 61685206 |
Filed Date | 2018-03-29 |
United States Patent
Application |
20180087864 |
Kind Code |
A1 |
Lowrance; Kyle ; et
al. |
March 29, 2018 |
Bolt Capture and Release Mechanism and Method for an Imitation
Machine Gun
Abstract
Electromagnetic force holds a reciprocatively movable bolt in a
charged position in resistance to compressive force from a bolt
actuating spring, while generating recoil impacts that simulate
firing rounds of ammunition from an ammunition belt in imitation
machine gun. Terminating the electromagnetic force allows the
compressive force from the actuating spring to move the bolt from
the charged position after simulating the firing of the last round
from the ammunition belt.
Inventors: |
Lowrance; Kyle;
(Westminster, CO) ; Cohlmia; C. Ross; (Arvada,
CO) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Pathfinder Systems, Inc. |
Arvada |
CO |
US |
|
|
Assignee: |
PATHFINDER SYSTEMS, INC.
Arvada
CO
|
Family ID: |
61685206 |
Appl. No.: |
14/541559 |
Filed: |
November 14, 2014 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F41A 33/06 20130101;
F41A 33/00 20130101; F41A 9/34 20130101 |
International
Class: |
F41A 33/06 20060101
F41A033/06 |
Claims
1. A bolt capture and release mechanism for an imitation machine
gun, the imitation machine gun having a reciprocatively movable
bolt which is biased by an actuating spring, the bolt requiring
manual movement in one direction against compression force from the
actuating spring to charge the bolt and thereby enable the gun to
fire simulated ammunition rounds from a simulated ammunition belt
loaded into the gun, and the bolt moving in the opposite direction
from the compression force of the actuating spring after firing of
the last simulated round, the imitation machine gun also including
a recoil simulator device which generates a recoil impact that
simulates firing each simulated round, the bolt capture and release
mechanism comprising: an electromagnet adapted to be stationarily
positioned on the imitation machine gun at a position adjacent to
bolt when the bolt is manually moved to a position to charge the
bolt, the electromagnet developing electromagnetic attracting force
on the bolt to hold the bolt in the charged position during the
recoil impacts generated by the recoil simulator device when
simulating firing each round of ammunition of the ammunition belt,
and the electromagnet terminating the attracting force to allow the
compressive force from the actuating spring to drive the bolt in
the opposite direction from the charged position after the last
recoil impact generated by recoil simulator device which simulates
firing the last round of ammunition of the ammunition belt.
2. A bolt capture and release mechanism as defined in claim 1,
further comprising: an armature adapted to be attached to the bolt
at a position to be adjacent to the electromagnet when the bolt is
in the charged position, the armature formed of non-magnetizing
ferrous material which attractively interacts with the
electromagnetic attracting force from the electromagnet to hold the
bolt in the charged position during the recoil impacts generated by
the recoil simulator device, the non-magnetizing ferrous material
of the armature ceasing the attracting interaction with the
electromagnet upon termination of the electromagnetic attracting
force from the electromagnet.
3. A bolt capture and release mechanism as defined in claim 2,
further comprising: a detent mechanism attached to the imitation
machine gun and interactive with the bolt to apply mechanical
resistance force on the bolt in the charged position to resist the
compressive force from the actuating spring.
4. A bolt capture and release mechanism as defined in claim 3,
wherein: the bolt defines an angled surface; the detent mechanism
comprises a plunger having a contact surface which is biased into
contact with the angled surface of the bolt to create the
mechanical resistance force; and the compressive force of the
actuating spring is sufficient to overcome the mechanical
resistance force on the bolt from the detent mechanism when the
electromagnet terminates the electromagnetic attracting force.
5. A bolt capture and release mechanism as defined in claim 3,
wherein: the electromagnetic force from the electromagnet is
sufficient to hold the bolt in the charged position during recoil
impacts generated by the recoil simulation device without the
mechanical resistance force on the bolt supplied by the detent
mechanism.
6. A method of capturing a reciprocatively movable bolt of an
imitation machine gun in a position representative of charging the
bolt and then releasing the bolt from the charged position after
simulatively firing rounds of an ammunition belt, comprising:
biasing the bolt with compressive force from a bolt actuating
spring; manually moving the bolt against the compression force from
the actuating spring to charge the bolt; applying electromagnetic
attracting force to hold the bolt in the charged position while
generating recoil impacts in the imitation machine gun that
simulate firing each round of simulated ammunition; and terminating
the electromagnetic attracting force and allowing the compressive
force from the actuating spring to move the bolt in the opposite
direction from the charged position after generating the last
recoil impact which simulates firing the last round from the
ammunition belt.
7. A method as defined in claim 6, further comprising: attaching an
armature to the bolt; interacting the armature with the
electromagnetic attracting force to hold the bolt in the charged
position while generating the recoil impacts.
8. A method as defined in claim 7, further comprising: applying
mechanical resistance force on the bolt in the charged position in
addition to the electromagnetic attracting force to resist the
compressive force from the actuating spring.
9. A method as defined in claim 8, further comprising: applying the
mechanical resistance force from a detent mechanism which is
attached to the imitation machine gun and which interacts with the
bolt.
10. A method as defined in claim 9, further comprising: contacting
a contact surface of a plunger of the detent mechanism with an
angled surface of the bolt to create the mechanical resistance
force.
11. A method as defined in claim 10, further comprising: biasing
the contact surface of the plunger into contact with the angled
surface of the ridge to create the mechanical resistance force.
12. A method as defined in claim 11, further comprising: overcoming
the mechanical resistance force on the bolt with the compressive
force from the actuating spring upon terminating the
electromagnetic attracting force to move the bolt in the opposite
direction from the charged position.
13. A method as defined in claim 8, further comprising: creating
sufficient electromagnetic attracting force on the bolt to hold the
bolt in the charged position during recoil impacts generated
without assistance from the mechanical resistance force on the
bolt.
14. A method as defined in claim 13, further comprising: overcoming
the mechanical resistance force on the bolt with the compressive
force from the actuating spring upon terminating the
electromagnetic attracting force to move the bolt in the opposite
direction from the charged position.
15. A method as defined in claim 6, wherein: enabling the
generation of recoil impacts by manually moving the bolt to the
charged position.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This invention is related to an invention for a Recoil
Simulator and Method for an Imitation Machine Gun, described in
U.S. patent application Ser. No. ______, filed concurrently
herewith, and assigned to the assignee of the present invention.
The subject matter of this application is incorporated herein fully
by this reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to training persons to
operate an actual machine gun by using an imitation or simulated
machine gun. More particularly, the present invention relates to a
new and improved bolt capture and release mechanism and method
which more reliably and fully simulates, with an imitation machine
gun, the requirement to charge the bolt after loading an ammunition
belt to enable firing the machine gun.
BACKGROUND OF THE INVENTION
[0003] In modern circumstances, it is difficult and expensive to
train soldiers and military defense personnel in the effective use
of high-powered rapid-fire machine guns, by simply allowing such
individuals to practice using the actual guns with live ammunition.
The ammunition rounds are expensive, for example costing up to five
dollars per round. The cost of ammunition alone quickly multiplies
when it is recognized that a typical machine gun is capable of
firing hundreds of rounds per minute. Adequate space for a practice
gunnery range may not be readily available. Increased cost is
involved in transporting the personnel and the equipment to
suitable remote locations where adequate gunnery practice can be
performed. Safety is always a major consideration when live
ammunition rounds are fired, both to military personnel involved in
gunnery practice and to non-military personnel who may be adjacent
to the gunnery range. It is difficult to instruct during a live
ammunition training session due to the noise and safety
considerations involved when others are involved in similar,
close-by, live-ammunition practice activities. Furthermore, it may
be difficult to vary the targets quickly at a live-ammunition
gunnery range.
[0004] These problems and practical constraints are exacerbated
when training individuals to shoot from a moving vehicle such as a
helicopter. If live ammunition practice is attempted from a moving
helicopter, a large space is required in order to maneuver the
helicopter and to provide targets and adequate safety barriers,
especially when multiple individuals are involved in similar
simultaneous training exercises. As a result, live gun practice
requires considerable space, and the cost of operating the
helicopter greatly multiplies the overall training cost.
[0005] Because of these and other considerations, simulated weapon
training programs have been developed for teaching purposes. Such
training programs use imitation machine guns which closely simulate
the sensational aspects and the mechanical and physical
requirements of firing actual machine guns. Firing is simulated by
reproducing effects which mirror the sensual perceptions associated
with firing the actual machine gun. The environment and the targets
are electronically displayed, allowing them to be more easily
varied and to simulate movement of the targets and the machine gun.
The trajectory of the simulated bullet fired is also calculated. In
those cases where the simulated fired bullet emulates a tracer, the
trajectory of that simulated bullet is also displayed in the
surrounding environment.
[0006] For helicopter gun training, the imitation machine gun is
mounted in an open door of an imitation portion of the helicopter
fuselage. The environment and the targets are displayed outside of
the open door. The portion of the imitation helicopter fuselage is
moved or shaken in a manner similar to the movement of an actual
helicopter in flight while the display of the surrounding
environment and the targets are moved to simulate the flight path
of the helicopter.
[0007] Simulated weapons training programs offer other benefits.
Environments of remote areas of the world may be simulated, thereby
providing training exposure to such environments prior to actually
deploying the military personnel to those locales. The accuracy of
the training program and the abilities of the individuals trained
may be assessed. The accuracy in shooting, and the success of the
training itself, is gauged by comparing the calculated, projected
trajectory of the simulated bullets relative to the displayed
targets. The number of simulated rounds fired may also be counted
to evaluate the efficiency of the individual doing the shooting.
Other factors can be evaluated from the vast amount of information
available from such computer-based simulated weapons training
programs.
[0008] Of course, to be effective for training purposes, it is
necessary to create a realistic simulated environment and a
realistic experience of firing the imitation machine gun. Such
simulation is accomplished principally by multiple computer systems
which are programmed to perform their specific simulation
activities in coordination with each other. In the end, the
capability of the simulated weapons training program to imitate the
actual use of the actual machine gun in an actual environment is
the ultimate measure of effective and successful training.
[0009] Individuals become accustomed to the imitation machine gun
due to the amount of simulated training received. Because of the
familiarity gained from training with the imitation machine gun,
use of the imitation machine gun should be essentially the same as
the use of the actual machine gun; otherwise, differences in
functionality or performance create unexpected problems or
difficulties when using the actual machine gun.
[0010] One of the important aspects of training with an imitation
machine gun is to simulate the recoil of firing an actual machine
gun. Recoil in an actual machine gun occurs in response to firing
an ammunition round. A momentary rearward impact occurs in reaction
to the forward acceleration of the bullet moving out of the barrel
and in reaction to a reciprocating movement of an internal bolt of
the gun. The explosive force from firing the round drives the bolt
rearward against the force of a bolt actuating spring. The rearward
movement of the bolt automatically ejects the spent casing,
withdraws the next live round from the ammunition belt, expels a
connection link which joined the withdrawn round to the next round
of the ammunition belt, positions the withdrawn round on the bolt
for loading and firing, and advances the ammunition belt to locate
the next round to undergo similar actions after active round has
been fired. Depressing the trigger enables the compressed bolt
actuating spring to drive the bolt forward to load the round into a
firing chamber and then fire that loaded round. The pressure from
the exploded round drives the bolt rearwardly against the
compression force of the bolt actuating spring. The sequence of
events continues in the same manner with each subsequent pull of
the trigger, or the sequence of events continues repetitively and
continuously while the trigger remains depressed. Each ammunition
round fired, accompanied by the reciprocating movement of the bolt
in the manner described, creates a reactive impact. The individual
operating the gun feels the sensation of this reaction as recoil of
the machine gun. One very effective recoil simulation device, and
its method of use, are described in the above-referenced US patent
application.
[0011] To ready an actual machine gun for firing live ammunition
rounds from a newly-loaded ammunition belt loaded, the operator
must "charge" the bolt. Charging the bolt involves manually moving
the bolt rearward against the force of the internal bolt actuating
spring. Charging the bolt removes the first round from the
ammunition belt and positions the removed round on the bolt for
loading and firing. Charging the bolt enables the compressed bolt
actuating spring to drive the bolt forward to load and fire the
round. Thereafter, the explosion from firing that round drives the
bolt rearward and compresses the bolt actuating spring to enable
the continuous repetition of these actions with each subsequent
pull of the trigger or on a continuous basis while the trigger
remains depressed.
[0012] Loading a simulated ammunition belt in an imitation machine
gun is also an important part of training to use the actual machine
gun. The imitation machine gun must emulate the functionality of
charging the bolt each time a new simulated ammunition belt is
loaded. After simulated ammunition belt is loaded and the bolt is
charged, the recoil simulator mechanism of the imitation machine
gun simulates the recoil impacts generated by firing rounds and the
reciprocation of the bolt. When the last round of the simulated
ammunition belt is fired stimulatively, the bolt is released from
its charged position. The bolt in the imitation machine gun
thereafter assumes the same position that the bolt of an actual
machine gun assumes after the last round of an actual ammunition
belt has been fired.
[0013] One previous technique used in an imitation machine gun to
simulate the action of charging the bolt involves holding the bolt
in the charged position after the bolt has been manually charged by
the operator. A holding pawl of the imitation machine gun pivots
into contact with the bolt in the charged position to restrain the
bolt against the considerable compression force from the bolt
actuating spring. A spring pivots the holding pawl into position to
restrain the bolt when the bolt is charged. The holding pawl is
intended to restrain the bolt while the recoil simulation device
generates the impacts which simulate firing the rounds from the
simulated ammunition belt loaded into the imitation machine gun. A
solenoid acts against the holding pawl to pivot it and release the
bolt when all of the rounds of the simulated ammunition belt have
been fired stimulatively. The released bolt moves forward to the
position of the bolt in an actual machine gun after the last round
of an actual ammunition belt has been fired. Thereafter, in both
the actual and the imitation machine guns, a new ammunition belt
must be loaded and the bolt must be charged before firing can
commence again.
[0014] Often, the frictional forces acting on the holding pawl from
the bolt and the forces from the pawl holding spring are too much
for the solenoid to overcome and release the bolt. A failure to
release the bolt when all of the rounds of the simulated ammunition
belt has been fired stimulatively prevents the user from executing
all of the actions necessary to load another simulated ammunition
belt and ready the imitation machine gun for firing. On the other
hand, if the pawl holding spring is weakened enough to allow the
solenoid to pivot the pawl and release the bolt, the pawl holding
spring is typically not strong enough to maintain the holding pawl
in the bolt restraining position under the influence of repetitive
recoil impacts generated by the recoil simulation device. Under
such circumstances, the bolt is released prematurely before all of
the rounds of the simulated ammunition belt have been fired.
[0015] In both cases, where the bolt is not released after all of
the rounds of the simulated ammunition belt have been fired
stimulatively, or where the bolt is released prematurely before all
the rounds of the simulated ammunition belt have been fired
stimulatively, dissimilarities in the performance of the imitation
machine gun compared to the actual machine gun occur. The operator
of the imitation machine gun is required to perform different and
unusual activities which are not involved in operating the actual
machine gun. As a result, the quality of the training is
compromised. Furthermore, the resulting erratic effects have the
potential of adversely influencing the coordination of the computer
systems which control the simulated weapons training program,
because those computer systems anticipate firing the full number of
simulated rounds of the simulated ammunition belt. As a result, the
training experience may be disrupted.
SUMMARY OF THE INVENTION
[0016] The present invention overcomes the previous problems of
holding and releasing the bolt in an imitation machine gun. The
problems of failing to release the bolt after all of the rounds of
the simulated ammunition belt have been fired and of prematurely
releasing the bolt prior to firing the anticipated number of rounds
of the simulated ammunition belt, are avoided by the present
invention. In addition, the present invention diminishes the risk
of loss of coordination among the control systems in the training
simulator resulting from a premature or failed release of the bolt
during training. As a consequence, training with an imitation
machine gun which employs the present invention is more effective
and realistic, and the individuals trained are more capable of
properly operating the actual machine gun in actual
circumstances.
[0017] In accordance with the above described and other related
considerations, a bolt capture and release mechanism and method of
present invention involves simulating realistically, in an
imitation machine gun, the action of charging the bolt required to
fire an actual machine gun after loading a new ammunition belt. The
present invention also reliably retains the charged bolt under the
repeated impacts generated by a recoil simulation device simulating
the firing of ammunition rounds. Further still, the present
invention allows realistic training of charging the bolt after
simulatively firing all of the rounds of an actual ammunition belt
and loading another simulated ammunition belt.
[0018] The bolt capture and release mechanism of the present
invention is used in an imitation machine gun to simulate actions
required to charge the bolt of an actual machine gun. The imitation
machine gun has a reciprocatively movable bolt which is biased by a
bolt actuating spring. The bolt requires manual movement in one
direction against compression force from the actuating spring to
charge the bolt and thereby enable the gun to fire simulated rounds
of ammunition from a simulated ammunition belt loaded into the gun.
The bolt is movable in the opposite direction from the compression
force of the actuating spring after firing of the last simulated
round of the ammunition belt. The gun includes a recoil simulator
device which generates recoil impacts that simulate firing each
simulated round from the simulated ammunition belt.
[0019] The bolt capture and release mechanism comprises an
electromagnet adapted to be stationarily positioned on the
imitation machine gun at a position adjacent to bolt when the bolt
is manually moved to a position to charge the bolt. The
electromagnet develops sufficient electromagnetic attracting force
on the bolt to hold the bolt in the charged position during the
recoil impacts generated by the recoil simulator device when
simulating the firing rounds from the ammunition belt. The
electromagnetic force is terminated to allow the compressive force
from the bolt actuating spring to move the bolt in the opposite
direction from the charged position when the recoil simulation
device generates the last recoil impact that simulates firing the
last round of an ammunition belt.
[0020] A subsidiary feature of the bolt capture and release
mechanism involves an armature adapted to be attached to the bolt
at a position to be adjacent to the electromagnetic when the bolt
is in the charged position. The armature is formed of magnetic
material which attractively interacts with the electromagnetic
force from the electromagnet to hold the bolt in the charged
position during the recoil impacts generated by the recoil
simulator device.
[0021] Another subsidiary feature of the bolt capture and release
mechanism involves a detent mechanism which is attached to the gun
and interactive with the bolt to apply mechanical resistance force
on the bolt in the charged position to assist in resisting the
compressive force from the bolt actuating spring. The detent
mechanism comprises a plunger having a contact surface which is
biased into contact with an angled surface of the bolt. The
compressive force of the bolt actuating spring is sufficient to
overcome the mechanical resistance force from the detent when the
electromagnet stops creating the electromagnetic attracting force.
However, it is preferred that the electromagnetic force from the
electromagnet is sufficient to hold the bolt in the charged
position during the recoil impacts apart from the mechanical
resistance force supplied by the detent mechanism.
[0022] The invention also involves a method of capturing a
reciprocatively movable bolt in a charged position and selectively
releasing the bolt, in an imitation machine gun. The method
involves biasing the bolt with compressive force from a bolt
actuating spring, manually moving the bolt against the compression
force from the actuating spring to charge the bolt, applying
electromagnetic force on the bolt to hold the bolt in the charged
position while generating recoil impacts that simulate firing
rounds of simulated ammunition from an ammunition belt, and
terminating the electromagnetic force on the bolt and allowing the
compressive force from the actuating spring to move the bolt in the
opposite direction from the charged position after simulating the
firing the last round from the ammunition belt.
[0023] Subsidiary features of the method involve some or all of the
following: attaching an armature to the bolt and attracting the
armature with the electromagnetic force to hold the bolt in the
charged position during the recoil impacts generated by the recoil
simulator device; applying mechanical resistance force on the bolt
in the charged position in addition to the electromagnetic force to
resist the compressive force from the actuating spring; overcoming
the mechanical resistance force with compressive force from the
actuating spring upon terminating the electromagnetic force to move
the bolt in the opposite direction from the charged position; and
enabling the generation of recoil impacts by manually moving the
bolt to the charged position.
[0024] Other aspects and features of the invention, and a more
complete appreciation of the present invention, as well as the
manner in which the present invention achieves the above and other
improvements and benefits, can be obtained by reference to the
following detailed description of a presently preferred embodiment
of the invention taken in connection with the accompanying drawings
which are briefly summarized below, and by reference to the
appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a generalized perspective view of an exemplary
imitation machine gun which incorporates and embodies a bolt
capture and release mechanism and method according to the present
invention.
[0026] FIG. 2 is a perspective view of the imitation machine gun
shown in FIG. 1, taken from the perspective on the opposite side of
the imitation machine gun from that shown in FIG. 1, illustrating a
charging handle used in charging the bolt, with the charging handle
in the position occupied when the bolt has been charged.
[0027] FIG. 3 is a partial exploded and perspective view of the
imitation machine gun shown in FIG. 2, illustrating the charging
handle, the bolt and components of the bolt capture and release
mechanism and a detent mechanism in an exploded relationship
relative to the gun.
[0028] FIG. 4 is a vertical section view taken through a housing of
the imitation machine gun shown in FIG. 2, illustrating the bolt in
a forward position from which the bolt must be charged.
[0029] FIG. 5 is a view similar to FIG. 4, illustrating the bolt in
a rearward position after the bolt has been charged.
[0030] FIG. 6 is a perspective view of the detent mechanism of the
bolt capture and release mechanism shown in FIGS. 3-5.
[0031] FIG. 7 is an exploded perspective view of the components of
the detent mechanism shown in FIG. 6.
[0032] FIGS. 8 and 9 are enlarged views of portions of FIG. 5.
[0033] FIG. 10 is a flowchart of a sequence of actions performed by
a user and by bolt capture and release mechanism when using the
imitation machine gun shown in FIGS. 1-9.
DETAILED DESCRIPTION
[0034] An imitation machine gun 20 which is used in simulated
weapons training activities is shown in FIGS. 1 and 2. The machine
gun 20 duplicates the look and feel and the mechanical features of
an actual machine gun. The machine gun 20 includes a bolt 22 (FIGS.
3-5) which must be charged to start firing ammunition rounds from a
simulated ammunition belt (not shown) taken from an ammunition box
24 (FIG. 1). Charging the bolt 22 involves manually moving the bolt
22 rearward against the force of a bolt actuating spring 26 (FIGS.
3-5). In an actual machine gun, charging the bolt removes a live
ammunition round from the ammunition belt and moves the live
ammunition round into position on the bolt 22 for loading and
firing when the trigger is pulled. Pulling the trigger allows the
actuating spring 26 to drive the ammunition round into the chamber
and fire it.
[0035] Charging the bolt is accomplished by pulling a charging
handle 28 rearwardly, as shown in FIGS. 2 and 3. The charging
handle 28 is connected to the bolt 22 and is located at the
exterior of a housing 30 of the gun 20. A barrel 32 of the gun 20
extends forward from the housing 30. FIG. 4 illustrates the
position of the bolt 22 prior to charging, and FIGS. 2 and 5
illustrate the position of the charging handle 28 and the bolt 22
after charging. In an actual machine gun, the bolt is charged
automatically from explosive force from firing an ammunition round.
The compression force from the actuating spring drives the bolt
forward to load the ammunition round and fire it when a trigger of
the gun is depressed or pulled. Reciprocation of the bolt occurs
continuously while the trigger remains depressed.
[0036] Unlike an actual machine gun, the imitation machine gun 20
does not reciprocate the bolt 22 to simulate firing ammunition
rounds. Instead, once the bolt is charged by the physical rearward
movement imparted from the charging handle 28, a bolt capture and
release mechanism 34 (FIGS. 3-5) holds the bolt 22 in the rearward
position, despite the fact that a trigger 36 (FIGS. 4 and 5) is
depressed. A recoil simulation device 38 (FIG. 2) simulates firing
each ammunition round by shaking or reciprocating the machine gun
20 in a forward and backward motion to simulate the recoil impact
of firing each live ammunition round with an actual machine gun.
After all of the rounds of the ammunition belt have simulatively
fired as replicated by recoil impacts generated by the recoil
simulation device 38, the bolt capture and release mechanism 34
releases the bolt 22. The actuating spring 26 moves the bolt 22
forward to the position (FIG. 4) where a new simulated ammunition
belt can be loaded and the bolt can thereafter be charged (FIG. 5)
to initiate firing the simulated rounds from the newly-loaded
ammunition belt. The bolt capture and release mechanism 34 is
particularly effective in holding the bolt under the adverse
vibrations generated by the recoil simulation device 38.
[0037] To perform the recoil simulation, the machine gun 20 is
supported by a split cradle assembly 40 which mounts the gun 20 to
a support pedestal 42, as shown in FIGS. 1 and 2. The support
pedestal 42 is attached to a floor or other support structure which
emulates the actual environment in which the actual machine gun
will be used, for example an opening in the side of a helicopter
fuselage. The split cradle assembly 40 is formed by an upper
movable cradle piece 44 and a separate lower stationary cradle
piece 46. The gun 20 is rigidly attached to the movable piece 44,
and the stationary piece 46 is rigidly attached to the pedestal 42.
The recoil simulation device 38 is operatively connected to create
relative movement between the cradle pieces 44 and 46, thereby
simulating recoil associated with firing an actual machine gun. An
example of a recoil simulation device 38 is described in the
above-referenced US patent application. An actual machine gun is
supported by a integral cradle assembly formed as a single unitary
piece.
[0038] The bolt 22 with which the capture and release mechanism 34
interacts, is substantially similar in size, shape and inertial
momentum to an actual bolt of an actual machine gun. The bolt 22 is
supported for movement by rails (not specifically shown) within the
housing 30, shown in FIGS. 3-5. The bolt 22 moves along a guide rod
48 which extends longitudinally within the housing 30 and parallel
to the barrel 32. The bolt actuating spring 26 surrounds the guide
rod 48. The bolt actuating spring 26 and the guide rod 48 extend
within an annular opening 50 which is formed longitudinally within
the bolt 22. A front end 52 of the actuating spring 26 contacts a
front end wall 54 of the annular opening 50 in the bolt 22, as is
also shown in FIG. 8. The front end wall 54 is formed by a radially
inward stepped portion of the bolt 22 adjacent to a
reduced-diameter opening 56 in the bolt 22. The reduced diameter
opening 56 constitutes a bearing for the bolt 22 when it
reciprocates along the guide rod 48. A rear end 58 of the actuating
spring 26 contacts a rear connector 60 which is attached to the
rear end of the guide rod 48. The rear connector 60 is also
attached rigidly to the floor of the housing 30. In this manner,
the bolt actuating spring 26 surrounds the guide rod 48, and the
front and rear ends 52 and 58 of the bolt actuating spring contact
the end wall 54 and the connector structure 60, respectively.
[0039] When the bolt 22 is charged as shown in FIG. 5, the end wall
54 of the annular opening 50 moves toward the rear connector 60,
thereby compressing the bolt actuating spring 26 between its ends
52 and 58. The force of the compressed actuating spring 26 is
effectively applied between the bolt 22 at the end wall 54 of the
annular opening 50 and the housing 30 at its bottom floor. The
force from the compressed spring 26 is substantial, for example
between 50 and 300 pounds. The compression force replicates the
force of the bolt actuating spring of an actual machine gun. The
forward driving force of the compressed bolt actuating spring of
the actual machine gun must be substantial because that compression
force is instrumental in determining a quick repetitive firing
capability of the actual machine gun. Replicating the force
required to charge the bolt in an actual machine gun is important
in creating effective training with the imitation machine gun 20,
to enable an operator to become familiar with the level of physical
effort required to actually charge the bolt of the actual machine
gun. When the bolt 22 is released, the compression force from the
actuating spring 26 drives the bolt 22 forward to the position
shown in FIG. 4.
[0040] The charging handle 28 is connected to the side of the bolt
22, as understood from FIGS. 2 and 3. A shaft 62 connects the
charging handle 28 and the bolt 22. The shaft 62 moves along a slot
64 formed in the side of the housing 30. Charging the bolt is
accomplished by pulling rearwardly on the charging handle 28 on the
exterior of the housing 24. Charging the bolt moves the bolt 22 to
the rearward position within the housing 30, as shown in FIG.
5.
[0041] More details of the bolt capture and release mechanism 34
are understood by reference to FIGS. 3-5. A rear end of the bolt 22
includes an upstanding transverse bracket 66. An armature 68 is
rigidly attached to the rear end of the bracket 66. The armature 68
is formed of a non-magnetized and impact resistant ferrous
material, such as cold-rolled and nickel plated steel. An
electromagnet 70 is located at a rear position within the housing
24. Charging the bolt by pulling the charging handle 28 to move the
bolt 22 rearwardly positions the armature 68 in close adjacency to
or in contact with the electromagnet 70 (FIG. 5). The electromagnet
70 is formed in the typical manner to include coils of a current
carrying conductor (not specifically shown). The electromagnet 70
creates a magnetic field which attracts the armature 68 and holds
the bolt 22 in the rearward position of the bolt when charged. The
number of coils in the electromagnet 70 and the amount of current
conducted by the conductor of the electromagnet 70 establish the
strength of the magnetic field, and consequently the strength of
the holding force on the bolt 22. The amount of holding force
created by the electromagnet 70 is substantial enough to reliably
hold the bolt 22 in the charged position against the substantial
force from the compressed bolt actuating spring 26, even under the
conditions of vigorous vibrations and shaking created by the recoil
simulation device 38 when simulating the firing of ammunition
rounds.
[0042] So long as adequate electrical current is applied to the
electromagnet 70, the magnetic attracting force between the
electromagnet 70 and the armature 68 retains the bolt 22 in the
rearward charged position. The electromagnet 70 retains the bolt 22
in the charged position while simulating the firing of all of the
ammunition rounds of an actual ammunition belt. Once all of the
simulated rounds of the ammunition belt have been fired, the flow
of electrical current to the electromagnet 70 is terminated. The
magnetic attracting force between the electromagnet 70 and the
armature 68 ceases, and the bolt 22 moves forward under the force
of the compressed bolt actuating spring 26. The forward movement of
the bolt 22 simulates the movement of the bolt in the actual
machine gun after the last live ammunition round of the actual
ammunition belt has been fired and no further live ammunition
rounds are available from the ammunition belt.
[0043] In order to continue firing the imitation machine gun 20, as
understood from FIGS. 1 and 2, the operator must replace the
ammunition box 24 with a new ammunition box, and load a new
simulated ammunition belt (not shown) from that box 24 into the
imitation machine gun 20. Loading the simulated ammunition belt is
accomplished by removing the used ammunition box 24 from a support
tray 72 which extends transversely from the housing 30 on the
opposite side of the charging handle 28, placing a new ammunition
box onto the support tray 72, opening a top cover 74 of the housing
30 to gain access to an ammunition belt feedway 76 formed in the
housing 30, opening the top cover of the ammunition box 24,
withdrawing the simulated ammunition belt from the box 24, placing
simulated ammunition belt in the feedway 76, and closing the top
cover 72 over the simulated ammunition belt. The ammunition box 24
is actual size, but the simulated ammunition belt within the box 24
is only of a limited length necessary to extend from the opened box
24 into the belt feedway 76. To load the simulated ammunition belt
in this manner, the bolt 22 must be located in the forward position
(FIG. 4).
[0044] A detent mechanism 78 of the bolt capture and release
mechanism 34 is shown in FIGS. 3, 6 and 7 and is used to assist the
electromagnet 70 in holding the bolt 22 in the rearward position
against the compression force of the bolt actuating spring 26. A
body 80 of the detent mechanism 78 is attached by bolts 82 to the
bottom floor of the housing 30. A plunger 84 is positioned within a
vertical annular opening 86 in the body 80. The plunger 84 is
biased upward from the annular opening 86 by a spring 88. The
spring 88 is located within the annular opening 86 in the body 80
and in an annular recess 89 in the plunger 84. The spring 88 is
compressed between the plunger 84 and the body 80. A flat surface
90 is formed in the side wall of the plunger 84, and a pin 92
extends transversely across an edge of the annular opening 86
adjacent to the flat surface 90. The pin 92, which extends through
the body 80, interacts with the flat surface 90 and retains the
plunger 84 for movement within the annular opening 86. The axial
extent of the flat surface 90 along the side of the plunger 84 also
controls the degree to which the plunger will move in the annular
opening 86 relative to the body 80.
[0045] A frustroconical shaped contact surface 94 is formed on the
upper end of the plunger 84 which protrudes out of the body 80. The
contact surface 94 interacts with an angled surface 96 of a
downward facing middle ridge 98 formed on the bottom center of the
bolt 22, as shown in FIGS. 5 and 8. When the bolt 22 has been
charged and is in the rearward position, the contact surface 94 of
the plunger 84 contacts the angled surface 96 of the ridge 98, as
shown in FIG. 8.
[0046] The resistance created by the interaction and contact
between angled surface 96 of the ridge 98 and the contact surface
94 of the plunger 84 when biased upwardly by the compressed spring
26, creates resistance to forward movement of the bolt 22. The
amount of resistance created by the detent mechanism 78 assists the
electromagnet 70 in holding the bolt 22 in the rearward position
(FIG. 5) under the influence of the compressed bolt actuating
spring 26. However, when the attracting force from the
electromagnet 70 ceases, the resistance from the detent mechanism
78 is insufficient by itself to prevent the compressed bolt
actuating spring 26 from moving the bolt 22 forward (FIG. 4). The
compressed actuating spring 26 forces the angled surface 96 forward
along the contact surface 94 and pushes the plunger 84 downward
into the body 80. In this manner, the detent mechanism 78 assists
the electromagnet 70 in holding the bolt 22 in the charged
position, but does not restrict forward movement of the bolt 22
when the electromagnetic attracting force from the electromagnet 70
on the armature 68 ceases.
[0047] The detent mechanism 78 allows the size of the electromagnet
70 to be reduced compared to the size of the electromagnet 70
required to hold the bolt 22 in the charged position by itself
without the assistance of the detent mechanism 78. However the bolt
capture and release mechanism 34 of the present invention also
contemplates use of a sufficiently sized electromagnet 70 which
generates sufficient electromagnetic force to hold the bolt in the
charged position without use of the detent mechanism 78.
[0048] A trigger mechanism 100 of the imitation machine gun 20 is
of the same construction as the trigger mechanism of an actual
machine gun, as shown in FIGS. 4, 5 and 9. The trigger mechanism
100 is located in a handle 102 which is gripped by the operator
when firing the gun. The trigger 36 is part of the trigger
mechanism 100, and the trigger 36 extends from the front surface of
the handle 102 to be squeezed by a finger of the operator. The
trigger 36 is interconnected with a pawl 104, and the pawl 104
interacts with a notch 106 formed in a lower rear ridge 108 of the
bolt 22 located at a rear end of the bolt 22. When the trigger 36
is not depressed, the pawl 104 extends upwardly into the notch 106
and prevents the bolt 22 from moving forward. Preventing the bolt
22 from moving forward prevents firing of the machine gun. When the
trigger 36 is depressed, the pawl 104 is withdrawn from the notch
106, and the bolt 22 is free to move forward under the influence of
the bolt actuating spring 26, and thereby fire the actual machine
gun. So long as the trigger 36 is depressed, the pawl 104 does not
prevent the automatic, continuous reciprocating action of the bolt
while firing the actual machine gun.
[0049] In the imitation machine gun 20, the bolt 22 does not move
forward during simulated firing. Instead, depressing the trigger 36
and holding it in a depressed condition causes the recoil
simulation device 38 (FIG. 2) to reciprocate the imitation machine
gun 20 in a manner which simulates firing ammunition rounds. An
electrical switch (not shown) is connected to the trigger 36 to
derive a control signal for activating the recoil simulation device
38. The electromagnet 70 holds the bolt 22 in the rearward charged
position (FIG. 5) while the recoil simulation device replicates
firing the rounds of ammunition belt.
[0050] Each individual recoil impact from of the recoil simulation
device 38 is sensed and counted to determine the number of
simulated rounds fired. Once the number of simulated rounds of an
actual ammunition belt have been counted as fired, the recoil
simulation device stops generating recoil impacts and the
energizing current to the electromagnet 70 is terminated, allowing
the bolt 22 to move forward to the position where another simulated
ammunition belt must be loaded to continue use of the imitation
machine gun 20.
[0051] A sequence 110 of actions which summarize the previously
described use and functions of the bolt capture and release
mechanism 34 in the imitation machine gun 20 is shown in FIG. 10.
The sequence 110 begins when the simulated ammunition belt is
loaded into the gun 20, as shown at 112. The simulated ammunition
belt represents the predetermined number of rounds of an actual
ammunition belt which will be fired by the imitation machine gun.
Loading the simulated ammunition belt at 112 enables the operator
to charge the bolt 22 at 114, by pulling the charging handle 28
rearward against the compressive force of the bolt actuating spring
26 (FIGS. 2 and 5). The pawl 104 of the trigger mechanism 100 (FIG.
9) holds the bolt 22 in the charged position (FIG. 5). The
electromagnet 70 is then energized, at 116, by conducting current
through the electrical conductors of the electromagnet. The
electromagnet 70 generates sufficient electromagnetic attracting
force which interacts with the armature 68 attached to the bolt 22
(FIG. 5) to hold the bolt 22 in the charged position. The
electromagnet 70 holds the bolt 22 in the charged position when the
trigger 36 (FIGS. 4, 5 and 9) is pulled, at 118. Pulling the
trigger activates the recoil simulator device 38 (FIG. 2) to
generate a recoil impact for each simulated round of ammunition
fired while the trigger is depressed, as shown at 120. The number
of simulated rounds fired is counted at 122. Because the number of
rounds of an actual ammunition belt is known, the count at 122 of
fired simulated ammunition rounds is compared to the number of
known rounds in the actual ammunition belt at 124. So long as the
number counted at 122 of simulated ammunition rounds fired is less
than the predetermined number of rounds of the actual ammunition
belt, the process reverts to 118, where continued depression of the
trigger results in firing more simulated rounds at 120 and counting
them at 122. Whenever the number of counted rounds at 122 equals
the predetermined number of rounds of the actual ammunition belt,
as determined at 124, the electromagnet 70 is de-energized at 126.
De-energizing the electromagnet at 126 allows the bolt 22 to move
forward in response to the compressive force from the actuating
spring 26 (FIG. 4). The bolt 22 then occupies the same position
(FIG. 4) as it would occupy in the actual machine gun after the
last round from an actual ammunition belt has been fired. The
operator is thereafter required to load a new simulated ammunition
belt to enable further use of the gun 20, as shown by the process
110 reverting back to that action at 112. The same process 110
thereafter continues with the newly loaded and each subsequently
newly loaded simulated ammunition belt.
[0052] The bolt capture and release mechanism 34 is capable of
long-term, intensive, reliable use without premature or unexpected
failure, thereby facilitating the effectiveness of training with
the imitation machine gun. The bolt capture and release mechanism
34 overcomes the unreliable operation of the prior art solenoid
actuated mechanism for holding the bolt in the charged position,
avoids failing to release the bolt after all of the rounds of the
simulated ammunition belt have been fired stimulatively, avoids the
premature release of the bolt prior to firing the anticipated
number of simulated rounds from the simulated ammunition belt, and
avoids a loss of coordination among the control systems in the
training simulator resulting from a failed, premature and/or
erratic release of the bolt during training. As a consequence, the
training with the imitation machine gun is more effective and
realistic, and the individuals trained are more capable of properly
operating the actual machine gun in actual circumstances.
[0053] The bolt capture and release mechanism 34 is concealed and
functional within the imitation machine gun in a way which does not
create significant differences in functionality, performance, look
and feel of the imitation machine gun relative to the actual
machine gun. No external additional parts appear on the imitation
machine gun to otherwise create subtle differences between the
imitation and actual machine guns, unlike the prior art solenoid
actuated pawl which is an added piece of equipment attached to the
outside of the machine gun housing. The imitation machine gun
achieves and maintains substantially the same functionality,
performance and physical feel of the actual machine gun. Other
advantages and improvements will become apparent upon gaining a
full appreciation of the present invention.
[0054] The above description is a description of a preferred
example of implementing the invention. The detail of this
description is not intended to limit the scope of the invention
except to the extent explicitly incorporated in the following
claims. The scope of the invention is defined by the following
claims.
* * * * *