JPH05500413A - Fire rate control mechanism for automatic firearms - Google Patents

Abstract

A trigger mechanism for controlling the firing rate of a gun (10) capable of fully automatic fire. The trigger mechanism comprises a timing device (54, 56) which cyclically interrupts the gun bolt (14) and is incorporated in the gun. The timing device (54, 56) is actuated independently of forces generated by the discharge of the gun so that the bolt (14) periodically is arrested to reduce its natural cyclic rate of movement during automatic firing.

Description

[Detailed description of the invention] one'-' Technical field The present invention applies to the firing rate control mechanism of firearms that can fire automatically, such as light machine guns. related.

Conventional technology It is well known that light machine guns have a tendency to "climb" during automatic firing. It is being As each salvo is fired, the firearm recoils upward and the muzzle is fired up to a certain degree. Tilt, then return to the original aiming point. Fire rate in fully automatic fire mode If the The missile will be fired at an angle, thus deflecting upward from the target. did Therefore, each successive salvo will be fired above the preceding salvo. . As a result, a phenomenon called ``climbing,'' i.e., reaching the goal After starting above the target, a phenomenon occurs in which the volley of fire climbs towards the top of the target. specific For firearms, as the rate of fire increases, the rate of "climb" tends to increase. There will be a change in direction.

A trained user can legitimately control 400 to 600 speeds per minute. It has been discovered that the firing rate is on the order of a single salvo. This operability is depends, at least to some extent, on the design and weight of the light machine gun, and also on the use It also depends on the level of training of the user. The important factors affecting the rate of fire are , the weight of the bolt and the travel distance of the bolt.

Previous attempts to reduce the size and weight of light machine guns - first, the size and weight of the bolt; necessitated a reduction in volume and a reduction in the distance the bolt was allowed to travel. Therefore As a result, the action of the bolt became faster, and the rate of fire of the firearm was approximately 600 rounds per minute. This resulted in exceeding the desired maximum speed. Therefore, for size reduction These efforts can vary the rate of climb of the firearm and improve the controllability of the firearm. This resulted in the loss of

Numerous efforts to control the rate of fire of light machine guns include increasing bolt mass and /Or the regulation of the movement of the sole was involved. When increasing the mass of the bolt, the gun Physical dimensions are reduced, but “dense metals” such as tungsten alloys are used. Actual weight of the bolt due to use or infilling of the bolt with lead The amount increases. This method is self-defeating in that it increases the overall weight of the gun. difference Additionally, even with the densest materials available, the rate of fire remains low. The decrease is only slight. Firing speed increased from 1.8°0 rpm to 1.50 Orpm Even if it decreases, it is far from the controllable reduction to 400-60Orpm. , "Lock-up", that is, regulation of the movement of the bolt by an inertia-operated mechanism. involves the use of the force created by the ejected bullet, and its inertial-actuated mechanism The disadvantage is that automatic firing of the gun becomes impossible if the gun fails; As a result, the rate of fire must be reduced enough to eliminate the climb. won.

The mechanism of the invention has a controllable rate of fire ranging from 400 to 60 Orpm. can be integrated into a light machine gun to provide a pistol-sized firearm with Ru. Additionally, the rate of fire may depend on fixed factors such as the weight of the breech or the distance traveled by the breech. not predetermined by the physical properties of being. The rate of fire is determined by the means built into the gun. The mechanism according to the invention is determined by testing to suit each gun. Therefore A light machine gun of a particular model firing in fully automatic firing mode fires each successive volley. Then, if you return to the aiming point of that gun within, say, 1/10 of a second, that particular gun will It is adjusted to fire 10 times, or at a rate of 600 rpm. for example, A different gun with a longer barrel or lighter frame, or with modified firing characteristics. For other guns that have other features that make firing more accurate, the rate of fire of such guns will adjusted to the rate of fire determined to be optimal for increasing the

The present invention provides a timing device that overcomes or at least alleviates the disadvantages of the prior art. Relating to a trigger mechanism consisting of. Therefore, the present invention determines the rate of fire of a gun. It consists of a timing device that can be actuated to to be ejected from a gun when the trigger of a trigger mechanism that is capable of firing is moved to the firing position. Fully automatic firing, cyclically interrupting the means for ejecting ammunition that becomes Provides a trigger mechanism for guns that can.

According to a feature of this aspect of the invention, a reciprocating bolt constitutes said ammunition ejection means. The bolt may reduce its inherent cyclic movement speed during automatic firing. It is regularly blocked to reduce The device is for controlling the movement of the bolt. Preferably, it is an electric timing device that operates the main reverse hook lever.

According to one feature of the invention, the timing device is activated by the trigger of the trigger mechanism of the gun. can be operated. In constructions where the timing device is trigger-actuated , the trigger mechanism is a hand for actuating the main barb lever for control of bolt movement. Each barb has a barb surface for cooperating with a bent member (bent) carried by the step. The trigger may be comprised of a trigger operably connected to a pair of barbs. gun is semi-automatic When set to dynamic firing mode, both inverted hooks of the pair of inverted hooks cooperate with the curved member. The trigger was retracted to release the bolt from the cocked configuration. When the curved member is released from the reverse hook surface of one reverse hook, and after firing the gun, the curved member is released from the reverse hook surface of the other reverse hook. be prevented by engagement with the reverse hook surface of the hook, provided that the trigger is not retracted. The gun is re-cocked while the bolt remains in the closed position to prevent movement of the bolt. When the trigger is released to bring the curved member into the one It is desirable that it engages with the reverse hook surface of the reverse hook.

During automatic firing of the gun, one barb activates the timing device; and the timing device regulates the movement of said other barb. can be controlled to reduce the natural circulation movement speed of the bolt. Regulates the movement of the reverse hook rotation for periodic engagement with the cam follower carried by said other barb. It is desirable that the timing device incorporates a possible cam.

The bolt and main barb have cooperating cam surfaces that engage when the bolt is retracted. Can be done. In this case, the main barrage is pivotably loaded to release and block said bolt. and controlled by a lever carried by said curved member.

During fully automatic firing of the gun, a fire mode selection switch is activated to activate said device. is placed in a position cooperating with said one barb; during semi-automatic firing of the gun, said one barb; To deactivate the device, the firing mode selection switch is removed from said cooperating position. It is desirable that

Another aspect of the invention is a type defined in any of the eight paragraphs above. To provide a gun incorporating a trigger mechanism consisting of a triggering device.

The fact that a gun incorporates a trigger mechanism according to the invention indicates that the gun is electrically fired. It must be emphasized that in the preferred embodiment The rate of fire of a gun is controlled by electrical or electronic means, whereas such Even if the means fails and becomes inoperable, the gun remains in semi-automatic or fully automatic mode. can operate. However, in such cases, firing will depend on the inherent circulation of that firearm. It is done at a rate of fire.

An embodiment of the invention will be described by way of example and with reference to the accompanying drawings, in which: FIG.

Brief description of the drawing Figure 1 shows a section of a light machine gun incorporating a trigger mechanism and timing device according to the invention FIG. 3 is a cross-sectional side view.

2 to 7 are enlarged views showing continuous operation of the trigger mechanism and timing device. Ru.

FIG. 8 is a plan view of the cam wheel and upper barb lever of the timing device.

Example Referring to FIG. 1, the light machine gun 10 has a breech 12, and the surface of the butt plate of the breech 12 is A bolt 14 (FIGS. 2 to 7) is reciprocatably and slidably disposed on the shaft. figure 2-7, the caul plate surface is indicated by a horizontal line 13.

The movement of the bolt is controlled by the frame of the gun at a pivot point 20 located below the caul plate surface 13. Controlled indirectly by a main bolt reverse hook lever 16 pivotally mounted on the front end of F. be done. At the opposite end of the frame F, on a pivot 22, a lever 16 Another carrying a curved member 25 for cooperating with a pair of delivery barbs, which will be described in detail below. is pivotally mounted on the lever 24 of. The lever 24 is mounted on a pivot 26 with a flange. The arm F is pivotably mounted between the upper and lower ends of the arm F. The trigger 28 has a pivot 3o is pivotally mounted to the gun frame at and by means of a connecting link 34 said pair of It is cooperatively connected to the lower barb 32 of the delivery barbs. Connection link 34 One end is pivotally connected to trigger 28 at pivot 36 and the opposite end is pivotally connected to trigger 28 at pivot 36. At 8, it is hinged to a lower barb 32. In order to control the movement of the curved member 25, The upper hook 40, which cooperates with the lower hook 32, is pivoted together with the lower hook 32. ] 2, pivotably mounted on the frame. The upper reverse hook 4o is the gun's Cam follower 4 cooperating with an actuating cam of a timing device 46 located in the tailboard carry 4.

In Figures 2-7, large arrows indicate in each case the trigger mechanism or The rate of fire control component is activated by the force of a spring or by In the case of control equipment components, either electric propulsion or other means of actuation Indicates the direction in which movement is prompted by something.

Referring to Figure 2, the trigger mechanism is shown when the gun is cocked and ready to fire. has been done. In this state, the bolt 14 is pulled by the main bolt reverse hook lever 16. It is kept in a contained state. However, the reverse hook surface 17 of the bolt and the curved member 15 are also shown by the arrows on bolt 14 to provide cooperating cam surfaces of 45 degrees each. The main spring force applied is greater than the main reverse hook return spring force indicated by the arrow on the lever 16. The bolt 14 is urged to move forward, and the bending member 15 moves the main bolt reverse hook lever 1. In order to forcibly butt against the reverse hook surface 17 of 6, the main bolt reverse hook lever 16 automatically releases the bolt. However, the main bolt reverse hook lever 16 cannot be held in the lever 24. Because they are directly connected, the curved member 25 of the lever 24 is connected to the reverse hook surface 33 of the reverse hook 32. When fixed to any of the reverse hook surfaces 41 of the reverse hook 40, the main bolt reverse hook lever 16 cannot move and therefore keeps the bolt 14 in the retracted position. hold In FIG. 2, the curved member 25 is connected to the barbed surface 41 by the barbed barb 40 below. is shown held in the .

As previously explained, the trigger 28 is connected to the lower barb 40 by the connecting link 34. Directly connected. As can be seen in Figure 2, the trigger is pulled back ( 2), and the lower reverse hook 40 is rotated clockwise (downward). is released, the engagement between the reverse hook surface 41 and the curved member 25 is released, and the lever 24 is pivoted. enable. As a result, the bolt is free to override the main bolt reverse hook lever 16. Now you can move forward (to the left in Figure 2) to fire the gun.

Clockwise movement of the upper delivery barb 32 is limited. The upper reverse hook 32 is It can only move until the surface 33' of the hook 32 meets the surface 41a of the reverse hook 41. I can't. In fact, the reverse hook 32 and the reverse hook 40 are as indicated by the juxtaposed arrows. , the surfaces 33a and 411 are pressed in the manner of an ordinary clothespin by equal and opposite spring forces. and are mutually biased. The pivot pin 38 protrudes in the axial direction. , the firing mode selection switch 3 shown in FIGS. 2-7 superimposed on the lever 24 and barb 32. 9 operates on three-stage surfaces S, F and A respectively. Firing mode selection switch 3 When 9 is in the lowest position 1, the surface S is pivoted to prevent pivoting movement of the barb 40 downwards. Aligns with the path of motion of bin 38 (FIG. 2). However, when firing, the firing mode When the selection switch 39 is placed in the intermediate position, the surface F is aligned with the path of movement of the pivot bin 38. Because of the alignment, the pivoting movement of the lower barb 40 can be limited. Therefore Then, the lower barb 4o is rotated by retraction of the trigger 28 via the connecting link 34. When rotated, the upper barb 32 also tends to rotate in the same direction as the lower barb 40.

The reverse hook surface 33a is used for the curved member 25 to pass between the surfaces 33a and 41a. It can be moved away from the barbed surface 41a by a distance that is sufficient.

In FIG. 2, when the curved member 25 engages the lower delivery barb surface 41, It will be appreciated that the curved member 25 is below the barb surface 33 of the upper barb 32. cormorant.

The firing mode selection switch 39 shown in FIG. 3 is set to semi-automatic firing mode. 0 When the firing mode selection switch 39 is in this firing mode position, the reverse hook 40 is , moves until the pivot pin 38 abuts the surface F of the firing mode selection switch 39. However, since it engages with the timing activation switch 54, 0 surface F does not allow the reverse hook 40 to move only when the reverse hook 40 is connected to the switch 54. Immediately before the engagement occurs, but immediately after the reverse hook 40 is released from engagement with the curved member 25. Afterwards, stop the reverse hook 40.

In FIG. 3, since the trigger is retracted, the feed reverse hook 40 is moved to the lever 2. 4, which is released from engagement with the curved member 25, shows the moment of disengagement. Also, since it is held in place by the curved member 25, the upper It can also be seen that the reverse hook 32 does not move downward.

FIG. 4 shows the relative position of the components of the trigger mechanism immediately after the position shown in FIG. Show location. The lever 24 is no longer held by the curved member 25 and is Therefore, the bolt 14 can also override the main bolt reverse hook lever 16. . As a result, the main bolt reverse hook lever 1G is pushed downward, and the lever 24 is reversed. It is released from the engagement of either hook 32 or 40 and rotates counterclockwise.

Of course, in order to release the bolt 14, the main bolt reverse hook lever 16 must be Must be moved below 3.

Referring to Figure 5, the trigger is still in the retracted (retracted) position. , the trigger component is shown in a position immediately following the position shown in FIG. has been done.

In this case, the bolt 14 has finished ejecting the bullet, and the bolt 14 does not support the ejection of the bullet along the breech. The main bolt reverse hook lever 16 is moved upward under the bias of the spring. The bolt moves forward and engages with the bolt at surfaces 15 and 17, causing the bolt to move forward. be able to prevent movement. When the main reverse hook lever 16 moves upward, The main reverse hook lever 16 simultaneously rotates the lever 24 clockwise and also rotates the lever 24 clockwise. The curved member 25 of the bar 24 is moved under the reverse hook surface 33 of the upper reverse hook 32 and beyond the same surface 33. and slide it. The reverse hook 32 is connected to the lower reverse hook 40 where the surfaces 33a and 418 meet. You will be able to freely return to your neutral position. In the process, the upper The reverse hook 32 engages with the curved member 25 on the reverse hook surface 33, and the bolt 14 engages with the curved member 25 on the surface 15. and a previous lever that can override the cam surface engagement at 17 24 is prevented from returning. As a result, the bolt is fixed in the retracted position.

To be able to fire the gun again in semi-automatic fire mode, The money must be released to reset the trigger mechanism. Referring again to Figure 2, , when the trigger 28 is released, the trigger 28 moves the lower barb 40 counterclockwise (upwards). ) Rotate.

This rotation is due to the engagement between the barbs 32 and 40 on the surfaces 32a and 41a. This also causes the upper reverse hook 32 to move upward. The upper barb 32 is curved on the surface 33 When released from engagement with member 25, surface 41 of lower barb 40 forms a curved portion. The material 25 is moved into position into engagement with the surface 41 of the lower barb 40. So After that, the gun is fully cocked and the trigger can be pulled again.

To engage the curved member 25 after the reverse hook 40 is released from engagement. If the upper barb 32 is not present, after the first salvo of ammunition is ejected from the gun, It is understood that the breech sole should be able to continue to move freely back and forth. It will be.

In full uncontrolled automatic fire mode, the firearm fires until the ammunition supply is exhausted and is fired until the trigger is released and the lower barb 40 engages the curved member 25 again. It should continue to shoot.

Control the movement of the bolt in order to fire the gun in a regulated fully automatic firing mode. The firing mode selection switch is activated so that the trigger mechanism activates the timing mechanism 46 for Engage switch 39.

Referring to FIG. 6, the firing mode selection switch 39 is in the highest position and the is shown to be aligned with the path of motion of the pivot bin 38. Launch mode selection When the selection switch 39 is in this position, the lower reverse hook 40 is triggered by the lower reverse hook 40. 28, it engages the timing activation switch 54 and The timing device 4 can be pivoted clockwise enough to press the timing device 4. 6 can be activated. When the timing device 46 is activated, a motor (not shown) that rotates the cam wheel 56 in a clockwise direction as viewed from above; (See Figure 8).

Other than the intervention of the firing mode selection switch 39, the various components of the trigger mechanism is in the position shown in FIG. 5 for semi-automatic firing mode. However, the trigger is retracted and held in the retracted position, and the initial salvo of ammunition is fired. After being taken out, the lower reverse hook 40 rotates and is released from engagement with the curved member 25. Also, since the upper reverse hook 32 is engaged with the curved member 25 again, the lower The reverse hook 40 only serves to hold the timing activation switch 54 in the pushed position. Not fulfilled.

In FIG. 8 the cam wheel is shown in plan view. Cam wheel 1 With each rotation, the cam lug 58, carried by the cam wheel, moves against the cover of the upper barb 32. The upper reverse hook 32 is rotated counterclockwise (upwards) and reversed. Release from the engagement on the hook surface 33. The gun has a cam 58 with an upper barb 32. It is fired every time it is released from engagement with the curved member 25, and then the upper reverse hook 32 is fired. It will engage with the curved member 25 again. This happens because the period of the cam is Only in cycles shorter than its own spontaneous firing period. As a safety feature , when the gun is cocked, reverse the cam lug upward until the trigger is fully retracted. cannot be engaged with the cam surface of the hook 32, therefore the automatic firing selection switch Even when the switch is engaged, insufficient trigger pull will cause the gun to become semi-automatic. Position the components of this mechanism so that it can be fired in firing mode can do.

The upper reverse hook 32 must be given time to re-engage with the curved member 25. No. The rate of fire can be infinitely reduced by various gearing or voltage changes etc. increase the rate of fire beyond the gun's natural unregulated rate of fire. It is not possible.

6 shows the trigger mechanism in the cocked state, and FIG. 7 shows the upper barb 32 in the cocked position. Cam-wheel in position for disengaging bar 24 from engagement with curved member 25 A cycle of timed automatic fire, indicating rule 56, will continue until the ammunition supply is exhausted. Or it will continue until the trigger is released again. When released, The trigger is configured such that the lower barb 40 can engage the curved member 25 of the lever 24. so that the lower barb 40 is released from engagement with the switch 54. This causes the timing motor and cam wheel 56 to stop operating. the Afterwards, if the gun is empty, it will be reloaded or fired again.

The trigger mechanism is constructed and arranged to reduce delivery forces on the curved member 25. It has become. As is common in known firearms, surfaces 15 and 17 are connected to the bottom of the bolt. Perpendicular to the direction of motion, for example, a principal spring force of 18 pounds will result in a force of about 6 pounds. It should create a force for sending out the reverse hook. However, the curved member of the bolt and the reverse hook surface The surface and main bolt reverse hook levers 16 must each be at an angle of 45 degrees with respect to the vertical. For example, the lower force of the main spring force of 18 pounds on the main bolt reverse hook lever 16 is The force in the direction is only 9 pounds, which is applied to the lever 24 at the connecting pivot 22. Reportedly. The curved member 25 of the lever 24 extends from the pivot 22 by twice the distance from the pivot 22. 6, the force transmitted to the curved member 25 of the lever 24 is This is half of the force acting on the connecting axis 22 of No. 4. Therefore, the force of 9 pounds is The curved member 25 for surface 33 or barbed surface 41 is ground to 4.5 lbs. reduced. Friction coefficient of 4.5 bond force between curved member 25 and inverted hook surfaces 33 and 34 number (depending on the finish of the mating surfaces) to a value as low as 0.5. Can be done. When the gun is set to regulated fully automatic fire mode, the upward barb 32 is an active sending-out reverse hook, so it also responds to the force of the return spring of the reverse hook 32. The actual delivery force that the timing device must overcome is 1 lb. It can be lower than 0.

In both semi-automatic and fully automatic firing modes, the lower barb 40 cocks the bolt. keep it in the correct condition. The lower barb 40 is manually controlled via the trigger 28. , the return spring of the downward barb can be made much heavier.

High precision is required when an extremely light trigger pull is required for semi-automatic firing. Therefore, the heavy tension force causes the engagement of the return spring to be temporarily released (during one firing). , a system that re-engages the trigger after it is released can be adopted. It is expected that

The return springs acting on the main bolt reverse hook lever 16 and lever 24 exert a greater force. By replacing the return spring with a return spring, the force for holding the sending out reverse hook 32 and reverse hook 40 can be increased. It can be further reduced.

Above, the main spring force of 18 bonds becomes a downward force of 9 bonds against the pivot pin 22. This example occurs because the spring force that pushes the main reverse hook lever 16 downward is This is limited to cases where the main bolt is not on the reverse hook lever 16. Main bolt reverse hook lever 16 upwards If the return spring exerting a force has, for example, a force of 4 bonds, the main bolt reverse hook lever The actual force transmitted downwardly to the -16 and connecting pivot 22 is 5 pounds, but Thus, the force exerted on curved member 25 is only 2.5 pounds. Lord of about 9 pounds The reverse hook return spring force cancels the downward force of the 9-bond transmitted by the bolt main spring. However, after that, the bolt should not move when the trigger is pulled.

The lever 24 has a mass above the pivot 26 with a mass equal to the mass of the lever below the pivot 26. There are some ugly parts. Lever 24 is an elongated component that prevents movement during recoil. placed perpendicular to the line.

The presence of this portion above the pivot pin 26 prevents the baying by the delivery barb 32 or 40. To cancel vibrations in the lever 24 that would adversely affect the fixation of the bending member 25.

The above embodiment employs a cam wheel to trip the upper barb 32. are doing. However, it conveys the necessary force and ensures upward reverse hook 32 in the required consistent period. Any device that can trip repeatedly can be used. It should be possible to do so. The movement of such devices is not rotational movement, but It should be possible to create a reciprocating motion similar to that produced by a lenoid.

The power source for actuating the trip device can be mechanical force, clockwork or gas pressure. It should be possible to do something other than electricity, like . However, in this example The timing device is a self-contained device and is sealed to the element. It has the advantage of being there. The expected lifespan of the timing device depends on the size of the battery. Depending on exceed. Incorporate a warning light into the timing device to indicate battery status be able to.

In an ideal case, the mechanism of the invention would be adopted for integration into an open bolt 91-light machine gun. option, but by replacing one type of bolt with another type, Closed bolts can be easily used. For this feature, accuracy is the most important In some cases, the gun may be used with a chain bolt, primarily in semi-automatic firing mode. possibly with the option of a fully automatic firing mode in an emergency situation. The gun may be used with a closed bolt if a gun is available. Do it like this.

In the unlikely event that the timing device malfunctions, it is normal to use the gun as a semi-automatic firearm. can be done. Another method is to engage the upper reverse hook 32 and move the curved member 25. A selector device (not shown) that holds the barb 32 out of the path of motion is attached to the gun. It is expected that they can be provided together. This selector device is unregulated. Allows the gun to fire in fully automatic firing mode.

Utilizes means such as an electric spark rather than a mechanical bolt to eject ammunition It is also expected that it will be possible to do so. When using means such as an electric spark , the timing device is adapted to control the release of the detonating spark.

Procedure amendment writing method) August 27, 1992 □Rudder Aso Watadono 1, 19 Cow Field 1991 Patent Application No. 501338 2. Name of the invention Fire rate control mechanism for automatic firearms 3. Person making the amendment 1.Relationship with oxen Patent applicant Name: Butushuman Limited 5. Date of amendment order: May 26, 1992 6. Claims increased by amendment number of terms 7. Subject of correction international search report 11-----＾--”N@PC〒/G!’1　+10/n1QgQ International Investigation Report Notice GB 9001969 S^　42707

Claims (12)

[Claims] 1. A trigger mechanism for a gun capable of fully automatic firing that physically to be fired when the displaceable trigger mechanism is moved to the firing position. To cyclically block the means for ejecting ammunition and determine the rate of fire of the gun A trigger mechanism characterized in that it consists of a timing device capable of operating. 2. Trigger mechanism according to claim 1, characterized in that the ammunition ejection velocity is virtually constant. A trigger mechanism characterized by. 3. 3. A trigger mechanism according to claim 1 or 2, wherein the ammunition ejection rate is determined by a timing device. A trigger mechanism characterized in that it is determined and independent of other characteristics of the firearm. 4. Trigger mechanism according to any of the preceding claims, characterized in that the ammunition ejection rate is electrically actuated. a trigger mechanism characterized in that it is determined by a dynamic timing device; 5. Trigger mechanism according to any of the preceding claims, wherein each barb is curved. comprising a pair of inverted hooks having inverted hook surfaces for cooperating with the member, said curved portion By means of actuating the main reverse hook lever for controlling the movement of the bolt A trigger mechanism characterized by being carried. 6. A trigger mechanism according to claim 5, wherein the gun is set in a semi-automatic firing mode. When the pair of reverse hooks together cooperate with the curved member to actuate the trigger mechanism. When the trigger is pulled in to When blocked, the curved member is released from the reverse hook surface of one reverse hook, To actuate the trigger mechanism, the trigger must be in the above position to prevent movement of the bolt. When the trigger is released again to cock the gun, the curved A trigger mechanism characterized in that a member is transferred and engages with a reverse hook surface of the one reverse hook. . 7. 7. A trigger mechanism according to claim 6, wherein said one barb during automatic firing of a gun. actuates the timing device, maintains the timing device in the actuated state, and The timing device regulates the movement of the other reverse hooks to prevent the natural circumferential movement of the bolt. Trigger mechanism characterized by speed reduction. 8. 8. A trigger mechanism according to claim 7, wherein the timing device is configured to trigger the reverse hook. cam followers and periodic carried by said other barbs to regulate movement. A trigger mechanism characterized by incorporating a rotatable cam for coupling to. 9. 6. The trigger mechanism according to claim 5, wherein the bolt and the main reverse hook have a bolt. There are cooperating cam surfaces that engage when retracted, and the main barb releases the bolt. is pivotally mounted to prevent A trigger mechanism characterized in that it is controlled by a trigger mechanism. 10. 7. A trigger mechanism according to claim 6, wherein during fully automatic firing of the gun, the trigger mechanism a mode selection switch cooperates with said one reverse hook to actuate said timing device; position and during the gun's semi-automatic firing mode, the firing mode selection switch is removed from cooperation with said one barring hook in order to stop the operation of the mining device; A trigger mechanism featuring: 11. Trigger machine for controlling the rate of fire of a gun that can perform fully automatic firing and which in fact has the same structure as described above with reference to the accompanying drawings and as shown in the accompanying drawings. A trigger mechanism characterized by: 12. A gun incorporating a trigger mechanism according to any of the preceding claims.