A hand-held automatic firearm comprises a trigger mechanism, which includes a hammer, arranged to be cocked as the breechblock recoils, a sustained-fire lever, controlled by the breechblock and locks the hammer as the breechblock advances, a trigger slider, movable by the trigger against spring force from an initial position to a single-shot position and further to a sustained-fire position, and a pair of mutually cooperating levers, which respectively constitute a release member and a disconnector member and are adapted each to enter the path of movement of a hammer extension and to assume a position that depends on the position of the trigger slider. The release lever and the disconnector lever are pivoted on a common upright pivot and have respective confronting camming side edges, which define between them a cam slot. A camming member is movable by the trigger slider and extends into said cam slot. The camming member moves in engagement with said camming edges as the trigger is pulled and by said movement causes pivotal movement of the pair of levers against the force of a restoring spring from an initial position, in which the release lever engages the hammer extension of the hammer when it is cocked, to a single-shot position, in which the release lever releases the hammer extension and the disconnector lever enters the path of said extension, and further to a sustained-fire position, in which the levers of said pair are disengaged from the hammer extension.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a hand-held automatic firearm comprising a 
trigger mechanism, a hammer, which is arranged to be cocked as the 
breech-block recoils, a sustained-fire lever, which is controlled by the 
breechblock and locks the hammer as the breechblock advances, a trigger 
slider, which is movable by the trigger against spring force from an 
initial position to a single-shot position and further to a sustained-fire 
position, and a pair of mutually cooperating levers, which respectively 
constitute a release member and a disconnector member and are adapted each 
to enter the path of movement of a hammer extension and to assume a 
position that depends on the position of the trigger slider. 
2. Description of the Prior Art 
Firearms which comprise a firing hammer and such trigger mechanism can be 
operated in a sustained-fire mode, in which the hammer is cocked by the 
breech-block as it recoils and the cocked hammer can be locked by the 
sustained-fire lever until the advancing breech-block has been locked, 
whereafter the sustained-fire lever under the control of the breechblock 
releases the hammer and the hammer strikes forwardly and by means of a 
firing pin fires the cartridge. In the sustained-fire mode that operation 
is continually repeated as long as the trigger remains pulled and only 
when the trigger is released do the disconnector and release members 
become effective so that just as during the single-shot mode they catch 
the cocked hammer and independently of the sustained-fire lever do not 
release the cocked hammer until the trigger is pulled again. In the 
single-shot mode the hammer is released by a movement of the release 
member as it engages a hammer extension from above and the disconnector 
member simultaneously enters the path of that hammer extension and during 
the next recoil automatically catches the hammer in its cocked position so 
that only one shot can be discharged. Upon the release of the trigger, the 
release member is moved rearwardly so that it again engages the hammer 
extension from above and the disconnector member leaves the path of the 
hammer extension when the release member has engaged the hammer extension. 
In the prior art, the release member and the disconnector member consist 
of generally upright levers, which are pivoted on transverse axes or 
consist of vertical sliders. That arrangement involves a considerable 
overall height and requires a substantial distance between the grip of the 
firearm and the line of recoil action. Besides, the handling of the 
firearm will be difficult and the accuracy of fire which can be achieved 
will be adversely affected. 
SUMMARY OF THE INVENTION 
It is an object of the invention to eliminate said disadvantages and to 
provide a hand-held automatic firearm which is of the kind described first 
hereinbefore and comprises a trigger mechanism which distinguishes by 
having a low overall height and a short length and consisting of 
relatively simple parts, which can economically be manufactured and in 
which firearm the trigger can reliably be pulled without a risk of 
trouble. 
That object is accomplished in accordance with the invention in that the 
release lever and the disconnector lever are pivoted on a common upright 
pivot and have respective confronting camming side edges, which define 
between them a cam slot, a camming member is provided, which is movable by 
the trigger slider and extends into said cam slot, the camming member is 
arrnged to move relative to the camming edges of the cam slot and in 
engagement with said edges as the trigger is pulled and by said movement 
to pivotally move the pair of levers against the force of a restoring 
spring from an initial position, in which the release lever engages the 
hammer extension of the hammer when it is cocked, to a single-shot 
position, in which the release lever releases the hammer extension and the 
disconnector lever enters the path of said extension, and further to a 
sustained-fire position, in which levers of said pair are disengaged from 
the hammer extension. In that arrangement the release lever and the 
disconnector lever constitute horizontal scissors, which have a very small 
height and length and permit an exact operation owing to a relatively 
simple camming mechanism. A reliable cooperation of all parts will be 
ensured because the levers are pivotally moved in a horizontal path into 
the path of the hammer extension and the relatively large area in which 
the catching surfaces of the levers and the hammer extension overlap each 
other even if the manufacturing tolerances are relatively large. The 
configuration of the camming edges and the movement of the slider, which 
is coupled to the trigger slider, are so selected, that the release lever 
and the disconnector lever can easily be moved relative to each other and 
relative to the path of the hammer extension when the trigger slider is in 
its single-shot or sustained-fire position so that the lever constitute 
robust and functionally satisfactory elements which can satisfactorily 
perform their required functions as a release member and a disconnector 
member in the single-shot and sustained-fire modes. 
In accordance with a desirable feature of the invention the camming member 
preferably consists of a roller and is mounted on a camming lever, which 
at one end is pivoted on an axis that is parallel to the axis of rotation 
of the pair of levers, whereas the camming lever at its other end extends 
into a coupling slot of the trigger slider. That arrangement will be 
simple in design and will ensure the required transmission of motion 
between the trigger slider and the camming member because a displacement 
of the trigger slider will positively impart a pivotal movement to the 
camming lever, which by that pivotal movement will move the camming member 
along an arc of a circle so that it will reliably perform its camming 
function. 
Within the scope of the invention that catching surface of the disconnector 
lever, which surface faces the hammer extension, may be offset to the 
direction of the striking movement of the hammer from the catching surface 
of the release lever. In that case the control of the hammer when it is 
caught by the disconnector lever will reliably be taken over by the 
release lever, which owing to its offset catching surface can reliably 
perform an inward pivotal movement until it is in its catching position in 
the path of the hammer extension before the disconnector releases the 
hammer extension so that the latter is then retained only by the release 
lever. 
A simple arrangement will also be provided if the restoring spring consists 
of a torsional coil spring for urging the levers of the pair toward each 
other and a safety device is provided for locking the release lever in its 
initial position. The torsional coil spring will then ensure a 
satisfactory cooperation of the camming edges and the camming member and 
the safety device will prevent an undesired pivotal movement of the 
release lever from its initial position under the action of shakes. 
The safety device may desirably consist of a two-armed locking lever, which 
is mounted on the camming lever for a stop-limited pivotal movement 
against spring force, and said locking lever may comprise a first lever 
arm, which protrudes into the path of movement of the hammer extension, 
which has a slip-off surface on the side that is remote from the 
breechblock, whereas the other lever arm of said locking lever has an 
indentation which interlocks with the release lever when the camming lever 
is in its initial position. When the camming lever is in its initial 
position, a mechanical locking of the release lever will be ensured in 
that arrangement and the release lever will automatically be released when 
the camming lever is pivotally moved for the discharge of a round. But in 
order to ensure that the release lever will not be blocked as the hammer 
moves rearwardly and that the engagement of the hammer extension by the 
release lever will not be prevented, the locking lever will be pushed 
aside by the hammer as it is cocked and the safety device will be disabled 
for a short time so that the release lever can move its catching surface 
out of the path of the hammer extension and a satisfactory cocking of the 
hammer and the catching of the hammer by the disconnector lever will not 
be prevented.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
An illustrative embodiment of the invention is strictly diagrammatically 
shown in the drawing. 
A hand-held automatic firearm comprises a receiver 1, which contains a 
trigger mechanism. The trigger mechanism comprises a hammer 4, which is 
pivoted on a horizontal transverse pivot 2 and is biased by a hammer 
spring 3. During the recoil of the breechblock 5, which is shown only in 
part, the hammer 4 is cocked. During the advance of the breechblock the 
hammer is locked by a breechblock-controlled sustained-fire lever 6 in 
that a hook portion 7 of the lever 6 engages a catching nose 4a of the 
hammer from below. 
The receiver 1 also contains a trigger slider 8, which is guided in the 
receiver 1 for a displacement against the force of a trigger spring 9 from 
an initial position to a single-fire position and to a sustained-fire 
position. By known means which are not shown in detail, the trigger slider 
8 is operatively connected to the trigger 8a. By means of the trigger 
slider 8, a pivotal movement is imparted to a camming lever 10, which is 
pivoted at one end on a vertical pivot 11 and at its other end extends 
into a coupling slot 12 of the trigger slider 8. A camming roller 13 is 
mounted on the camming lever and extends into a cam slot 16, which is 
defined by and between a pair of levers 14, 15. Said pair of levers are 
composed of a release lever 14 and a disconnector lever 15 and are pivoted 
on a common vertical pivot 17. A torsional coil spring 18 urges the levers 
14, 15 toward each other. In dependence on the position of the trigger 
slider 8, a movement of the camming roller 13 relative to the cam slot 16 
which is defined by the camming side edges 19, 20 of the pair of levers 
14, 15, the pair of levers 14, 15, which respectively serve as release and 
disconnector members, will perform the control movements which are 
required for single shots and for sustained fire. 
In the initial position shown in FIG. 2, the breechblock 5 is in its 
foremost position and the sustained-fire lever 6 has disengaged the cocked 
hammer 4, which is now caught because the catching surface 22 of the 
release lever 14 engages a hammer extension 21 from above. The catching 
surface 23 of the disconnector lever 15 is now disposed outside the path 
of the hammer extension 21. The firearm is ready to fire. 
When the trigger slider 8 is then pushed to its single-fire position 
against the force of the trigger spring 9 and is locked in that position 
by detent or locking means, not shown, the camming lever 10 will perform a 
pivotal movement about the pivot 11 and will cause the camming roller 13 
to urge the release lever 14 outwardly so that the hammer 4 is released 
and can cause the shot to be discharged. (FIG. 3). As soon as the hammer 
extension 21 has jumped up will the restoring spring 18 urge the 
disconnector connector lever 15 inwardly into the path of the hammer 
extension 21. As a result, the hammer 4 which has been cocked again by the 
recoiling breechblock will displace during its reverse pivotal movement 
the disconnector lever 15 by the hammer extension 21, which has a suitable 
slip-off surface. The disconnector lever 15 then immediately returns to 
its catching position (FIG. 4). When the breechblock 5 has advanced and 
the hammer 4 has subsequently been released by the sustained-fire lever 6, 
the catching surface 23 of the interruptor lever 15 will catch the hammer 
extension 21. As long as the trigger is pulled, a second round cannot be 
discharged and the next round cannot be discharged until the trigger is 
released and is then pulled again. Upon a release of the trigger, the 
trigger spring 9 will urge the trigger slider 8 back to its initial 
position, and the camming roller 13 will then perform a reverse pivotal 
movement to urge the disconnector lever 15 away from the hammer extension 
21 so that the control of the hammer 4 will pass from the disconnector 
lever 15 to the release lever 14, which has been swung in the meantime. To 
ensure a satisfactory transfer of the control, the respective catching 
surfaces 22, 23 of the release lever and the disconnector lever 14, 15 are 
offset in elevation as is apparent from FIG. 1. After the control of the 
hammer 4 has been taken over by the release lever 14, the hammer 4 is 
retained only by the release lever 14 (FIG. 2) so that the next round can 
now be discharged. 
For sustained fire, the trigger slider 8 must be moved beyond its 
single-fire position to its sustained-fire position shown in FIG. 5 so 
that a sufficiently large pivotal movement is imparted to the camming 
lever 10 and the camming roller 13 now moves the levers 14, 15 apart until 
the hammer extension 21 has entirely been released. Now the locking and 
release of the hammer 4 will be controlled only by the sustained-fire 
lever 5 and the fire will be sustained as long as the trigger is pulled. 
Upon a release of the trigger slider 8 returns to its initial position and 
the camming roller 13 again permits the pair of levers 14, 15 to influence 
the sequence of movements of the trigger mechanism. During the next 
reverse pivotal movement of the hammer 4 the hammer extension 21 will be 
engaged by the disconnector lever 15 and the control of the hammer 
extension 21 will subsequently be passed on to the release lever 14. The 
mechanism has been returned to the initial position shown in FIG. 2. 
As is shown in FIGS. 6 and 7, an undesired movement of the release lever 14 
by a shake can reliably be prevented in that a safety device 24 is 
provided, which mechanically locks the release lever 14 when it is in its 
initial position. That safety device comprises a two-armed locking lever 
25, which is pivoted to the camming lever 10 on an axis which coincides 
with the axis of the camming roller 13. By a locking spring 26 the locking 
lever 25 is held in a locking position relative to the camming lever 10. 
In that locking position one lever arm 27 of the locking lever overlies 
and covers the camming lever, the pair of levers 14, 15 are in their 
initial position and a locking nose 28 of the release lever 14 is received 
and positively locked by an indentation 29 of the locking lever so that 
the latter is mechanically locked (FIG. 6). In that locking position the 
second lever arm 30 of the locking lever 25 protrudes into the path of the 
hammer extension 21. When the trigger is then pulled so that the camming 
lever 10 is pivotally moved. The locking lever 25 will positively be moved 
in unison with the camming lever 10 and the safety device will be disabled 
in time for a release of the release lever 14 (FIG. 7). Because that 
pivotal movement causes also the lever arm 30 to move out of the path of 
the hammer extension 21, the round will properly be discharged. Upon a 
release of the trigger, the camming lever 10 will return to its initial 
position and the detent mechanism comprising the locking nose 28 and the 
indentation 29 will interlock again. But during the reverse cocking 
movement of the hammer 4 the slip-off surface 31 which is provided on said 
hammer 4 and is associated with the lever arm 30 can effect a temporary 
unlocking in that the locking lever 25 is urged away against the force of 
the locking spring (position indicated in phantom in FIG. 6) so that the 
release lever 14 can be moved aside in spite of the safety device 24 and 
can then be pivotally moved until it is locked by the sustained-fire lever 
6. 
Because the pair of levers 14, 15 acting as a release member and a 
disconnector member are horizotally arranged and perform a scissorlike 
control movement and because the cam slot defined by the pair of levers 
and the camming member carried by the camming lever cooperate in a simple 
manner, the mechanism is robust and can economically be made and mainly 
distinguishes by a small overall height and a short overall length.