US 3453764 A
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y 1969 e. GROLLEAU 3,453,764
ELECTRONIC FIRING MECHANISM Filed June 23, 1967 Sheet of 2 INVENTOR: GERARD GROLLEAU y 9 G. GROLLEAU 3,453,764
I ELECTRONIC FIRING MECHANISM Filed June 23, 1967 Sheet of 2 INVENTOR: GERARD GROLLEAU ATTORNEY United States Patent ,26 Int. Cl. F41c 19/12 US. CI. 42-84 3 Claims ABSTRACT OF THE DISCLOSURE In an electronic firing mechanism, an electro-magnet actuating a magnetizable lever, an automatic circuit closing contact, the opening of which makes conductive a transistor energising the electro-magnet and operating the firing pin.
Already known are firearms with electrical or electromagnetic firing mechanisms. The electro-magnet in such mechanisms is energised by the closing of a circuit with the aid of a contact made by the user. In order to fire, the user presses on the trigger to bring together the electrodes into contact.
The path which the movable electrode must travel is determined by the space between the two electrodes, this results in a time lag until the contact be effective, with a resulting loss in accuracy. During this time the arm may be moved by the operator.
Moreover, it is necessary that the space be constant and accurate. If the same varies, there will be variations in firing time. Additionally, foreign bodies can become lodged between the electrodes, preventing contact with occasioning firing accidents.
The present invention remedies all these disadvantages and permits absolutely instantaneous firings which are extremely precise and reproducible owing to its principle of operation which is based upon the breaking of a con-- tact, that is to say upon the moving apart of the electrodes.
To this effect, the invention is concerned with a trigger for firearms characterized by electronic means adapted for instantaneously causing, by opening of a contact, the energising of the electro-magnet controlling the movement of the firing pin.
According to a characteristic of the invention, the electronic means consist of a battery, a condenser, a resistance, a transistor, an electro-magnet, a switch and a starting member.
According to another characteristic of the invention, the firing mechanism is constituted independently of a support, a hammer and a spring, a hammer sear, a spring, a trigger and its pivot pin, an adjustable stop screw with its blocking counter screw and a guiding screw.
According to another characteristic of the invention, the trigger comprises a safety mechanism composed of a lock and of its spring.
The invetnion will be better understood by referring to the accompanying description made by way of non limiting example and to the drawing in which:
FIGURE 1 shows the electronic firing mechanism in percussion position,
FIGURE 2 shows the electronic firing mechanism in its cocked position,
FIGURE 3 shows a transversal view of the firing pin mechanism and a lock in safety position.
The various electric members adapted to the voltage used are connected in the following manner (FIGURE 2).
A conductive wire 31 going from the positive terminal 32 of battery 6 connects the starting command 4 at its sup- 3,453,764 Patented July 8, 1969 porting point 34 which is insulated from the mass of the firearm. On this wire 31 is connected a terminal 33 of condenser 28 as well as the emitter 39 of transistor 2. Then starting from support 34 current is directed to electrode 5 by means of a spring blade on which it is secured, current being transmitted to the fixed electrode 5 which serves as a stop for the movable electrode 5 Then starting from the fixed electrode 5 the latter being insulated from the starting member 4, another conductive wire 35 conducts the current to a terminal 36 of resistance 29 and to the base 37 of transistor 2 on which these latter are connected.
On the other hand, a conductive wire 26 starting from the negative terminal 27 of battery 6 conducts current to switch 19 (automatic circuit cutting contactor) on which is connected the other terminal of condenser 28 and of resistance 29 as well as the entry wire of electro-magnet coil 1. Finally, the outlet wire of said electro-magnet coil 1 is connected to the emitter 30 of transistor 2.
The circuit is closed when the arm is ready to be fired. The heel of hammer 8 in the cocked position maintains in contact the electrodes of switch 19 as shown in FIGURE 2. At the other end, the electrodes of the trigger 24 are in permanent contact. Current is weakly absorbed by transistor 2 without passing into electro-magnet coil 1.
The electrical circuit is broken by pulling on trigger 24 in the direction of arrow A. The electrodes 5 and 5 move away from one another, transistor 2 then allows the passage of current to electro-magnet 1 which is thereby energized and triggers th percussion by attracting to itself a pivoted magnetizable lever 12. Percussion takes place and hammer 8 which actuates the percussion means as well as switch 19 leaves the circuit open. It is only when the percussion mechanism is again cocked that the electrical circuit will again be closed.
It can readily be seen that the present system is also readily adaptable to small arms since in such arms it is not possible to readily install a conventional system which is percuted by the direct action of an electro-magnet whose core is propelled. This naturally requires a powerful electric magnet which in turn needs a large energy source.
Referring to FIGURE 1 the percussion mechanism is composed of a support 7, a hammer 8 and a spring 9, a hammer sear 10, a common spring 11, an adjustable stop screw 14 with a blocking counter screw 15 and a guiding screw 16. Spring 11 is compressed in a housing formed by mutually facing cut outs in lever 12 and sear 10. It will be noted that the front part of the cut out in sear 10 is formed by a part which is in contact with a locking part forming the front side of the cut out in lever 12. Obviously when lever 12 pivots upon being attracted by the electro-magnet 1, these two elements will no longer be in contact and sear 10, no longer locked, will release hammer 8. The arming of the trigger and percussion mechanism takes place simultaneously in the following manner.
The arming lever 17 is brought back in the direction of arrow A by grasping with the index finger the extremity 50 of the lever which projects outside stock 38 (FIGURE 3). The same pivots then on its pin 18 and thanks to its pin 52 applied against the front face of hammer 8, drives the same rearwardly and thus compresses its spring 9.
This rearward movement is continued until thebolt of the arming lever comes to strike against the edge of a notch made in the upper wall of the support piece 7 (not shown) to permit on the one hand its passage and on the other hand determine its stop when it comes in end of course against a stop. FIGURE 3 shows the safety lock 21 in the safety position. There can be seen in this figure the inwardly directed pin of arming lever 17 which is located in front of hammer 8 as well as the part of the same lever which is accessible on the outside of the Weapon. The
safety lock 21 has a spring 22 which urges it in front of hammer 8 and opposes its movement. When the arming lever 17 is pushed forward to the position shown in FIG- URE 1, the heel 54 thereof meets the chamfered head of lock 21 and causes the same to retract thereby allowing passage of hammer 8. The weapon is then ready for percussion. Movement of arming lever 17 causes lock 21 under the urging of its spring 22 to again move in front of the hammer and prevents it from moving. When the arming lever 17 is moved in the direction of arrow B, the heel 54 thereof again meets the chamfered head of lock 21 which projects in front of it and forces it to retract inside its housing.
To replace the safety lock when the weapon is cocked the arming lever is brought back in the direction of arrow A until the noise produced by the penetration of ball 23 in a recess provided in the inner surface of the lever is heard. This sort of locking of arming lever 17 defines a position thereof which allows its heel to free the safety lock 21 and to allow the same to move in front of hammer 8 and thereby again prevent percussion.
It will be appreciated that in-the locked position, the rear part of the hammer maintains the electrodes of switch 19 in contact with one another to-establish the circuit.
A predetermined movement of pieces 8 to 10 and 12 has taken place meanwhile and the engagement of said members corresponds at the stopping point of lever 17. It is thus that the notch made on the lower part of hammer 8 is located on a level with the head of sear 10. The latter moves upwardly against the urging of its spring 11 in the direction of arrow C, making possible the hooking of hammer 8. At this moment the head of lever 12 which forms a locking member is free and places itself under the heel of sear 10 (to prevent it from going down again) in a rotational movement around its shaft 13. This movement is limited by the adjustable stop screw 14 on which the lower part of lever 12 comes to bear against the urging of the same spring. It is maintained constantly compressed between the head of trigger 12 and sear 10 in which it is lodged. At the end of its travel, in its rearward movement, the rear extremity of hammer 8 projects outside its housing, in an opening made in the supporting piece 7, and meets a micro contact blade of the automatic circuit cutter 19 to drive it in order to apply it against its other contact point, thus permitting to establish the electrical cir cuit.
When the simultaneous and successive engagement of all the members 8, 10 and 12 is made, the arming lever is moved forward in the direction of arrow B in order to place it in its inoperative position. The hammer 8 is thus maintained in armed-position ready to strike the firing pin 20.
The present invention has numerous advantages:
The electronic trigger permits an absolute instantaneous operation since the tripping occurs at the moment of the cut olf (opening of the electrodes); there is thus elimination of the time lag represented by the path to be covered in order to travel over the spaced apart electrodes to make contact as in previously known systems. It permits to obtain a constant precision. The adjustment of the resistance (normally called sensitivity) cannot modify the spacing of the contacts.
The mechanism is practical and fool proof.
Perturbations in the operation due to foreign bodies coming between electrodes with irregular spacing, and adjustments are eliminated.
The percussion mechanism is very simple and easy to fabricate. In effect, the parts are not complicated and are reduced to a hammer, a sear and an arming lever.
With the exception of the arming lever, all parts of the percussion mechanism are cylindrical and can be mounted in a very simple housing.
The present mechanism eliminates critical engagement points of parts and the exact determination of distance between the centres, while reducing the number of spring needed.
All the percussion members are housed in a casing. They are thus protected from dust and from all factors which might prevent or modify their movement.
The mechanism constitutes an interchangeable compact unit which is readily accessible to the operator.
It is of sure functioning and is not sensitive to time lags resulting from inertia. The safety functions automatically by means of a single arming lever.
What is claimed is:
1. Electronic firing mechanism comprising an energizing circuit including a source of current and a transistor fed by said source; an electro-magnet, a switch having electrodes for feeding current from said transistor to said electro-magnet upon opening of said circuit; percussion means; a hammer movable between a front position in contact with said permission means and a rear position in which it maintains said electrodes in contact, a first spring urging said hammer toward said means, an arming lever having an externally accessible portion and an inwardly projecting portion in contact with said hammer for moving same; a pivoted magnetizable lever having a locking member, a sear for holding said hammer, said sear being held against said hammer by said locking member to maintain said hammer in said rear positions; a safety mechanism comprising a lock spring urged toward said arming lever and retractable thereby, said lock having a part projecting in front of said hammer; trigger means for opening said circuit and energizing said electro-magnet and thereby attracting thereto said magnetizable lever, causing References Cited UNITED STATES PATENTS 2,780,882 2/ 1957 Temple 4284 2,957,391 10/1960 Lovercheck 4284 3,208,181 9/1965 Calhoun et al. 4284 3,250,034 5/1966 Simmons 4284 BENJAMIN A. BORCHELT, Primary Examiner.