Patent Abstract:
The invention relates to a trigger system for hand firearms with a hammer, a catch allocated to the hammer, a trigger, and a trigger arm interacting with this trigger, wherein the hammer has a first stop for holding the hammer in a completely cocked position and the trigger arm has a first trigger arm stop edge for engaging with an associated first hammer stop of the hammer. In order to allow pulling of the trigger with lower trigger weight even in the double-action mode, the hammer contains a second stop for holding the hammer in a partially pre-cocked position and the trigger arm has a second trigger arm stop edge for engaging an associated second hammer stop of the hammer.

Full Description:
FIELD OF THE INVENTION  
       [0001]     The invention concerns a trigger system for hand firearms.  
       BACKGROUND OF THE INVENTION  
       [0002]     So-called single-action/double-action trigger systems for hand firearms are known, in which there is the ability to move the hammer, e.g., by means of an uncocking lever, in a controlled and safe way from a single-action position (hammer completely cocked) into a double-action position (hammer completely uncocked). However, in the double-action mode, such trigger systems feature a relatively high trigger weight, because here the hammer must be moved uncocked against the force of the mainspring into the cocked position for discharging a shot. However, the expenditure of force required for this purpose can lead to reduced shooting precision.  
       SUMMARY OF THE INVENTION  
       [0003]     An object of the invention is the design of a trigger system of the type named above, which enables triggering also in the double-action mode with lower trigger weight and which remains functional even for a failure to fire.  
         [0004]     This object is achieved by a trigger system as set forth in the claims. Preferred configurations and advantageous improvements of the invention are also provided in the claims.  
         [0005]     In comparison with known single-action/double-action trigger systems, the hammer is partially pre-cocked for the trigger system according to the invention in double-action mode and in this position also provides a favorable lever ratio of the stops of the engaged trigger arm and hammer to the hammer pin. Therefore, the double-action mode enables a trigger resistance that is smaller compared with conventional systems.  
         [0006]     A hand firearm equipped with the trigger system according to the invention can always be carried in a partially pre-cocked state, without the risk of unintentional discharge of a shot. In this partially pre-cocked state, the hammer is held in a partially cocked position, wherein, in this position, the mainspring force is not yet sufficient to insert a cartridge for firing. From this position, however, the trigger system can be activated with an expenditure of force that is smaller compared with conventional double-action systems, because the mainspring no longer has to be tensioned by the entire amount for triggering.  
         [0007]     Through repeating (manual activation of the action or through the action returning due to the recoil after the discharge of the first shot), the trigger system is led into a pre-cocked single-action position. From this position, the trigger system can be activated with low expenditure of force, because only the stop edge of the catch must be pressed out of the stop of the pre-cocked hammer. The force is transferred by means of the trigger, trigger arm, firing pin, and catch.  
         [0008]     Even if there is a failure to fire or empty striking (no cartridge in the cartridge block), activation of the trigger system is possible. Due to the second trigger arm stop edge and an associated second hammer stop, the hammer can then also be cocked and struck again. However, due to an unfavorable lever ratio of the here functional second trigger arm stop edge and the associated hammer stop to the pivot point of the hammer, a higher expenditure of force is required for drawing out of this position. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]     Other details and advantages of the invention result from the following description of a preferred embodiment with reference to the drawing. Shown are:  
         [0010]      FIG. 1 , a trigger system according to the invention for a hand firearm in a partially pre-cocked double-action position;  
         [0011]      FIG. 2 , the trigger system shown in  FIG. 1  for the activation of the trigger from the partially pre-cocked double-action position shown in  FIG. 1 ;  
         [0012]      FIG. 3 , the trigger system shown in  FIG. 1  in a cocked single-action position;  
         [0013]      FIG. 4 , the trigger system shown in  FIG. 1  after a failure to fire;  
         [0014]      FIG. 5 , the trigger arm of the trigger system shown in FIGS.  1  to  4  in a schematic perspective view;  
         [0015]      FIG. 6 , the hammer of the trigger system shown in FIGS.  1  to  4  in a schematic perspective view;  
         [0016]      FIG. 7 , the catch of the trigger system shown in FIGS.  1  to  4  in a schematic perspective view, and  
         [0017]      FIG. 8 , the firing pin of the trigger system shown in FIGS.  1  to  4  in a schematic perspective view. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0018]     The trigger system of a hand firearm shown schematically in different positions in  FIG. 1  to  4  contains a hammer  1  with a catch  2 , a trigger  3 , and a trigger arm  4 , which is connected in an articulated way to the trigger and by means of which, when the trigger  3  is pulled, the hammer  1  is first cocked against the force of a not-shown mainspring and then released for firing a shot. The trigger arm  4  is forced backwards and upwards by means of a not-shown trigger arm spring.  
         [0019]     As follows from the above descriptions of FIGS.  1  to  4 , the hammer  1  can rotate about a hammer pin  5  between two side parts of a handle or built-in part  6  spaced apart from each other. Between the two side parts of the handle or built-in part  6 , the catch  2  is mounted so that it can rotate about a transverse pin  7 . By means of this catch  2 , the hammer  1  is held in a partially pre-cocked position or a completely cocked position, which is explained below in more detail. The trigger  3  can rotate about a trigger pin  8  on the handle or built-in part  6 . It contains a link part  9  pointing diagonally upwards with a pivot pin  10 , on which the front end  11  of the trigger arm  4  is coupled.  
         [0020]     The trigger arm  4  shown separately in  FIG. 5  has on its front end  11  crimped inwards a bore  12  for placement on the pivot pin  10  of the trigger  3 . At its rear end  13  also crimped inwards, the trigger arm  4  has a radial cam  14  projecting upwards, a connecting piece  15  extending backwards with a control bevel  16  running diagonally upwards, and a section  17  bent inwards at a right angle in the direction of the hammer with a first lower trigger arm stop edge  18  and a second trigger arm stop edge  19  offset from the first edge towards the side and the top.  
         [0021]     As follows from  FIG. 6 , the hammer  1  has on its bottom side a radial cam  20  and a first lower hammer stop  21 . The hammer  1  further contains on its side facing the trigger arm  4  a second upper hammer stop  22  projecting laterally. The first hammer stop  21  is used for engaging the trigger arm stop edge  18 . In contrast, the second hammer stop  22 , which is offset above the first hammer stop  21  and towards the front relative to the first stop, is led into engagement with the trigger arm stop edge  19 . While the first hammer stop  21  is arranged at a side cutaway section  35  on the side of the hammer  1  facing the trigger arm  4 , the second hammer stop  22  is located on a side projection  36  on the side of the hammer  1  pointing towards the trigger arm  4 . Above the second hammer stop  22 , the hammer  1  also contains a transverse bore  23  for the hammer pin  5  shown in  FIG. 1 , by means of which the hammer  1  can rotate between the side parts of the handle or built-in part  6 . On the front side of the hammer  1 , there is also the upper and lower stop  24  or  25  for engaging the catch  2 .  
         [0022]     The catch  2  shown separately in  FIG. 7  has on its bottom side a catch stop  26  for engaging the stops  24  or  25  of the hammer  1 . The catch  2  also contains a carrier  27 , which projects laterally and which interacts with a carrier  33  of a firing pin  31  shown in  FIG. 8 . The catch  2  has on its front side a groove  28 , in which a leg spring is housed for pre-cocking the catch  2 . Furthermore, in the catch  2  there are two aligned bores  29  and  30  for the transverse pin  7 .  
         [0023]     In  FIG. 8 , the firing pin  31  is shown, which can also rotate about the transverse pin  7 . For this purpose, the firing pin  31  has a bore  32 . The firing pin  31  contains, in addition to the carrier  33  projecting downwards, a connecting piece  34 , which is bent inwards and which interacts with the connecting piece  14  of the trigger arm  4 .  
         [0024]     The function of the trigger system according to the invention is explained below with reference to FIGS.  1  to  4 , wherein, in the top illustration of each figure, the trigger arm  4  is shown completely and in the bottom illustration only the functional elements of the corresponding components are shown.  
         [0025]      FIG. 1  shows the trigger system in a partially pre-cocked double-action position. In this position, the catch stop  26  engages the catch  2  in the upper stop  24  of the hammer  1 , whereby the hammer  1  is held in a position in which the force of the not-shown mainspring would not yet be sufficient to fire a cartridge. As follows from the lower left illustration of  FIG. 1 , the hammer  1  can be activated by means of the lower trigger arm stop edge  18  interacting with the lower hammer stop  21 . Because the lower hammer stop  21  has a greater distance from the hammer pin  5  than the upper hammer stop  22 , the hammer  1  can be activated from this position with lower trigger resistance. The upper trigger arm stop edge  19  shown in the lower right illustration and the lower stop  25  of the hammer  1  are not functional in the partially pre-cocked double-action position.  
         [0026]     By pulling the trigger  3  in the partially pre-cocked double-action position shown in  FIG. 1 , the partially pre-cocked hammer  1  according to  FIG. 2  is cocked further by the trigger arm  4  over the lower trigger arm stop edge  18  engaged with the lower hammer stop  21 . During the cocking process, the trigger arm  4  is moved downwards over the cam bevel  16  of the trigger arm  4  contacting the hammer pin  5  in a position in which the trigger arm stop edge  18  is disengaged from the associated hammer stop  21  and thus the hammer  1  is released for firing a shot. In the course of the cocking process, the firing pin  31  is pivoted upwards by the radial cam  14  of the trigger arm  4 , which engages with the connecting piece  34  of the firing pin  31 . In this way, the catch  2  is also brought and held in a position that enables the striking of the hammer  1 , by means of the carrier  33  of the firing pin  31  and the associated side carrier  27  on the catch  2 .  
         [0027]      FIG. 3  shows the trigger system in a cocked single-action position. The trigger system assumes this position through repeating (manually drawing back the action or returning the action due to the recoil impulse from the discharge of a shot). In this single-action position, the hammer  1  is held in its completely cocked position through the engagement of the catch stop  26  in the lower stop  25  of the hammer  1 . When the trigger  3  is pulled, the firing pin  31  is pivoted upwards by the radial cam  14  of the trigger arm  4  and the connecting piece  34  of the firing pin  31 . In this way, the catch  2  is also rotated by the carrier  33  of the firing pin  31  and the associated side carrier  27  on the catch  2 , so that the catch stop  26  is lifted from the lower stop  25  of the hammer  1  and thus the hammer  1  is released. By means of an uncocking lever not shown here, the trigger system can be brought controlled and safely in a known way from the single-action position into the pre-cocked double-action position.  
         [0028]     In  FIG. 4 , the trigger system described above is shown in a position after a failure to fire or striking with an empty cartridge block. The hammer  1  is located in an uncocked front starting position. In this position, the trigger arm stop edge  19  engages with the upper hammer stop  22 . By pulling the trigger  3  again, the hammer  1  can be cocked and struck again by means of the trigger arm stop edge  19  and the upper hammer stop  22 . Because the upper hammer stop  22  has a smaller distance from the hammer pin  5  than the lower hammer stop  21 , here an increased expenditure of force is required. In this process, the trigger arm  4  is moved into a position in which the trigger arm stop edge  19  and the hammer stop  22  are no longer functional, by means of the similarly functional trigger arm stop edge  18  and the radial cam  20  on the hammer  1 .

Technology Classification (CPC): 5