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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
An imitation machine gun 20 which is used in simulated weapons training activities is shown in
Charging the bolt is accomplished by pulling a charging handle 28 rearwardly, as shown in
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 (
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
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
When the bolt 22 is charged as shown in
The charging handle 28 is connected to the side of the bolt 22, as understood from
More details of the bolt capture and release mechanism 34 are understood by reference to
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.
In order to continue firing the imitation machine gun 20, as understood from
A detent mechanism 78 of the bolt capture and release mechanism 34 is shown in
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
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 (
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.
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
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 (
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.
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
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.
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.
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.
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.