Patent Publication Number: US-2023152052-A1

Title: Firing pin safety of a firearm

Description:
TECHNICAL FIELD 
     The present invention relates to firing pin safeties for firearms, especially for automatic and semi-automatic firearms. More precisely the present invention relates to a firing pin safety of a firearm according to the preamble part of claim  1 . 
     BACKGROUND 
     One problem in firearms, usually in semi-automatic or automatic firearms, is a slamfire, which is a premature, unintended discharge of a firearm and which typically may occur, when a bolt of the firearm stops rapidly, while a firing pin continues its movement by inertia forward and hits and sets off a primer. Sometimes, the firing pin only causes a dent onto the primer but in the worst cases the slamfire occurs. Typically, the slamfire is prevented by providing the firing pin with a spring around it for slowing down the movement but in all cases the spring is not effective enough as the force of the spring is not enough to prevent the continuation of the movement of the firing pin. In case one should try to prevent the continuation of the movement of the firing pin in order to prevent the slamfire by increasing preventing force of the spring, it would also mean that the force of the striking hammer should also be increased, which may then cause subsequent problems in the firearm. 
     The firing pin may also move if the firearm is dropped by the user and the tip of the firing pin strike the primer of the ammunition inadvertently, which may even cause an accident. 
     In U.S. Pat. No. 6,145,234 is disclosed a firearm comprising a breechblock, a firing pin having a tip, a proximal end opposite the tip and a catch surface disposed in proximity to the proximal end, a hammer which is movable from a loaded position through a motion path to strike the firing pin, a firing pin spring biasing the firing pin into a rest position wherein the tip of the firing pin is adapted to be spaced from a percussion cap of a cartridge and a one-piece leaf spring including a spring arm supported on the breechblock, a safety catch disposed in proximity to the proximal end of the spring arm and having a first position wherein the safety catch engages the catch surface to secure the firing pin in the rest position and a second position wherein the safety catch disengages the catch surface to release the firing pin for movement out of the rest position, the spring arm biasing the safety catch into the first position, and a beveled release part disposed adjacent the proximal end of the spring arm, the beveled release part having a camming surface disposed within the motion path of the hammer when the safety catch is in the first position such that, as the hammer moves from the loaded position through the motion path, the hammer cams the camming surface of the beveled release part against the force of the spring arm to move the safety catch from the first position to the second position, and the hammer then strikes the proximal end of the firing pin to displace the firing pin from the rest position. 
     In U.S. Pat. No. 8,245,427 is disclosed a firearm, firing pin safety catch mechanism comprising a bolt having a face and proximal end for receiving a firing pin, a bolt carrier, a firing pin having a distil end, a proximal end opposite the distil end and a recess, or catch surface, disposed in proximity to the proximal end, a hammer which is moveable from a cocked position through a travel path to make contact with the firing pin, a firing pin spring biasing the firing pin into a rest portion wherein the distil end of the firing pin is designed to be spaced from the forward face of the bolt and a safety catch mechanism including a safety catch supported on the bolt carrier, rotating on a pin which is biased by a spring at one end; a safety catch which is disposed in proximity to the proximal end of the safety catch mechanism and having a first position wherein the safety catch engages the recess and secures the firing pin in the rest position and a second position wherein the safety catch disengaged the recess thereby releasing the firing pin for movement out of the rest position, the spring biasing the safety catch into the first position; and a camming surface located at the proximal end of the safety catch mechanism, the camming surface disposed within the travel path of the hammer when the safety catch is in the first position such that, as the hammer moves from the cocked position through the travel path, the hammer cams the camming surface of the distil end of the safety catch thereby disengaging the safety catch from the first position to the second position, by overcoming the force being imparted to the safety catch mechanism by the spring, thus allowing the hammer to strike the proximal end of the firing pin thereby displacing the firing pin from its rest position. 
     An object of the present invention is to create a firing pin safety of a firearm by which the above described problems relating to the possible slamfire are eliminated. 
     Another object of the present invention is to create an improved firing pin safety of a firearm, in which slamfire is prevented automatically. 
     SUMMARY 
     In order to achieve the above objects and those that will come apparent later the firing pin safety of a firearm is mainly characterized by the features of the characterizing part of claim  1 . 
     Dependent claims present advantageous features and embodiments of the invention. 
     According to the invention, the firing pin safety of a firearm, which firearm comprises a firing pin safety, a hammer, a bolt, a bolt carrier and a firing pin, in which the firing pin safety comprises a safety lever mounted on a bolt carrier of the firearm, which firing pin safety is configured to control movement of a firing pin of the firearm, wherein the safety lever and the hammer are integrated functionally, the safety lever is turnable and has three main positions: a basic position, in which position the safety lever retains movement of the firing pin to the primer of the cartridge and from inside the bolt, a release position, in which the safety lever actuated by the hammer releases movement of the firing pin towards the primer of the cartridge but not from inside the bolt, and a dismantle position, in which position the safety lever of the firing pin safety can be dismantled and the firing pin can be removed manually from inside the bolt of the firearm without tools. 
     According to an advantageous feature of the invention the hammer comprises a spring-loaded plunger configured to guide the safety lever of the firing pin safety. 
     According to an advantageous feature of the invention the hammer comprises a beveled surface configured to guide the safety lever of the firing pin safety. 
     According to an advantageous feature of the invention the safety lever comprises a bevel configured to provide turning of the safety lever. 
     According to an advantageous feature of the invention the firing pin comprises a breech head and the safety lever has form-fitting forms that correspond to form-fitting forms of the breech head of the firing pin configured to affect degrees of freedom of the firing ping subject to the position of the safety lever. 
     According to an advantageous feature of the invention the firing pin safety comprises a spring-loaded return plunger for returning the safety lever automatically to its basic position. 
     According to an advantageous feature of the invention the return plunger is locking the safety lever to the bolt carrier. 
     According to an advantageous feature of the invention the firing pin safety comprises ball bearing locking means configured to secure the safety lever in vertical direction by means of a ball recess in the bolt carrier. 
     According to an advantageous feature of the invention the firing pin safety comprises a return-spring for the firing pin and the firing pin comprises a groove for locking the spring by attachment of a last loop of the spring into the groove. 
     According to an advantageous feature of the invention the form-fitting forms of the safety lever comprise arch recesses and a shoulder part as well as a bearing surface and the form-fitting forms of the breech head of the firing pin comprise two shoulders and a recess between the shoulders. 
     According to an advantageous feature of the invention the safety lever of firing pin safety comprises a body provided with at least one on its outer surface extending inclined groove for dirt and/or dust removal. 
     According to an advantageous aspect of the invention the firing pin safety is integrated functionally and by the safety lever and its co-operation with the hammer of the firing pin based on the form-fitting positions&#39; location, the safety lever has integrated slamfire-prevention and inadvertent firing pin movement-prevention. 
     By the firing pin safety according to the invention the slamfire is prevented. Also, the firing ping safety according to the invention prevents the movement of the firing pin even if the firearm would be dropped by the user and thus, the danger of the tip of the firing pin striking the primer of the ammunition inadvertently is eliminated and the safe use of the firearm is increased. The firing pin safety according to the invention is also user-oriented having good ergonomic properties and provides for the possibility of easy dismantle for cleaning and/or maintenance. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the following the invention and its advantages are explained in greater detail below in the sense of example and with reference to accompanying drawing, where 
       In  FIG.  1 A  is schematically shown an advantageous example of a firearm. 
       In  FIGS.  1 B- 1 C  is schematically shown an advantageous example of a firing pin safety according to the invention. 
       In  FIG.  2    is schematically shown an advantageous example of a firing pin safety according to the invention. 
       In  FIG.  3    is schematically shown the example of  FIG.  2    seen from above. 
       In  FIG.  4    is schematically shown an advantageous example of the firing pin safety according to the invention in a basic position. 
       In  FIG.  5    is schematically shown an advantageous example of the firing pin safety according to the invention with a firing pin in a back position. 
       In  FIG.  6    is schematically shown an advantageous example of the firing pin safety according to the invention in a release position, when a firearm is fired. 
       In  FIG.  7    is shown the example of  FIG.  6    seen from above. 
       In the  FIG.  8    is schematically shown an advantageous example of the firing pin safety according to the invention. 
       In  FIG.  9    is schematically shown an advantageous example of the firing pin safety according to the invention. 
       In  FIG.  10    is shown the example of  FIG.  9    as s sectional view. 
       In  FIGS.  11  and  12    is schematically shown an advantageous example of the firing pin safety according to the invention indicating movement of a spring-loaded plunger. 
       In  FIG.  13    is schematically shown an advantageous example of the firing pin safety according to the invention. 
       In  FIG.  14    is schematically shown an advantageous example of the firing pin safety according to the invention. 
       In  FIG.  15    is schematically shown an advantageous example of the firing pin safety according to the invention. 
       In the  FIG.  16    is schematically shown an advantageous example of the firing pin safety according to the invention. 
       In  FIG.  17    is schematically shown an advantageous example of the firing pin safety according to the invention in a dismantle position. 
       In  FIGS.  18 - 22    is schematically shown an advantageous example of the firing pin and the safety lever in the different positions of the firing pin safety according to the invention. 
       In  FIGS.  23 - 28    is schematically shown another advantageous example of the firing pin safety according to the invention. 
     
    
    
     DETAILED DESCRIPTION 
     During the course of the following description like numbers and signs will be used to identify like elements according to the different views which illustrate the invention and its advantageous examples. In the figures some repetitive reference signs may have been omitted for clarity reasons. 
     In the  FIG.  1 A  is shown an example of a firearm  100  comprising a firing pin safety  10  below an upper body  31  of the firearm  100 . 
     As shown in the example of  FIGS.  1 B- 1 C  the firing pin safety  10  comprises a safety lever  11  with a bevel  19  attached to a bolt carrier  12  for a bolt  18  located around and for effecting the positions of a firing pin  15 . The firing pin  15  has a breech head  16 , to which an impact is caused by a hammer  17  for effecting position changes of the firing pin  15 . In this example a spring-loaded plunger  25  is provided on top of the hammer  17  for guiding during firing the safety lever  11  of the firing pin safety  10  to side and enables back-turning closing the upper receiver with the hammer  17  in the discharged position. 
     In the  FIG.  2    is shown an example of the firing pin safety  10 . The firing pin safety comprises the safety lever  11  mounted on the bolt carrier  12 . In the  FIG.  2    the safety lever  11  is in a basic position, in which position it retains the movement of the firing pin  15  and the breech head  16  forwards such that the firing pin  15  cannot move freely nor meet a primer of an ammunition. The basic position is the default position of the safety lever  11  of the firing pin safety  10 , to which default position the safety lever  11  of the firing pin safety tends to return from any other positions. 
     In the  FIG.  3    is shown the example of  FIG.  2    seen from above. In this example the safety lever  11  of the firing pin safety  10  is in the basic position i.e. in the default position to which the safety lever  11  of the firing pin safety  10  tends to return from any other positions. In the default position i.e. in the basic position the breech head  16  of the firing pin  15  extends outwards and the hammer  17  is cocked. 
     In the sectional view of the  FIG.  4    is shown the position, in which the hammer  17  is armed and ready to strike the breech head  16  of the firing pin  15 , as can be seen in the  FIG.  4    below the safety lever  11  in protruded position. The safety lever  11  is in the basic position retaining movement of the firing pin  15 . 
     In the example of the  FIG.  5    the firing pin  15  is in a back position, in which the safety lever  11  of the firing pin safety  10  prevents protruding of the firing pin  15  out from the bolt  18 . 
     In the example of the  FIG.  6    the firearm is discharged and the hammer  17  strikes the breech head  16  of the firing pin  15 . Before meeting the breech head  16  the hammer  17  turns the safety lever  11  of the firing pin safety  10  to right in the figure and releases movement of the firing pin  15  such, that the firing pin  15  can strike the primer of the ammunition. Now the safety lever  11  of the firing pin safety  10  is in a release position. 
     In the  FIG.  7    is shown the example of  FIG.  6    seen from above. The safety lever  11  of the firing pin safety  10  has turned due to the movement of the hammer  17  to the release position and released the movement of the firing pin  15 . The safety lever  11  meets the hammer  17 , which provides the turning of the safety lever  11  to the side. At the end of the movement the hammer  17  strikes the breech head  16  of the firing pin  15  and the firearm is discharged. 
     As can be seen from the example of the  FIG.  8    the firing pin  15  has a movement frontwards and protrudes out from the bolt  18 . 
     In the example of the  FIG.  9    an upper receiver (not shown) of the firearm  10  has been turned open with the hammer  17  in a discharged position as the hammer  17  has returned to the front position. The spring-loaded plunger  25  on top of the hammer  17  guides during firing the safety lever  11  of the firing pin safety  10  to side and enables back-turning closing the upper receiver with the hammer  17  in the discharged position. 
     In the sectional view of the example of the  FIG.  10    the upper body  31  has been set down and the spring-loaded plunger  25  on top of the hammer  17  moves down with the down-setting of the upper body  31  during its final stages. The evasive means provided by the spring-loaded plunger  25  prevent the hammer  17  to collide with the safety lever  11  during down-setting of the upper body  31 . When the firearm is loaded the hammer  17  slides backwards against bottom surface of the safety lever  11  of the firing pin safety  10  and returns to full upper position, when it has slid off from below the safety lever  11 . Thus, the position is the same as in the stage, where the firearm is cocked, and the hammer  17  with the spring-loaded plunger  25  is functionable for the movement of the safety lever  11  of the firing pin safety  10  to side. 
     In the examples of the  FIGS.  11  and  12    the spring-loaded plunger  25  moves downwards in the hammer  17  and tends to return to the upper position of the  FIG.  11   , in which it functions as turning means for the safety lever  11  of the firing pin safety  10 , as well as the spring-loaded plunger  25  functions as the evasive means during down-setting of the upper body  31 , as can be seen from the  FIG.  12   . 
     As can be seen from the example of the  FIG.  13    as the evasive means for the hammer  17  also an in upper edge beveled surface  26  can be used, along which beveled surface  26  the safety lever  11  of the firing pin safety  10  turns during down-setting of the upper body  31  and does not collide with the hammer  17 . The right front corner of the hammer  17  functions during firing as the turning means for the safety lever  11  of the firing pin safety  10 . 
     In the example of the  FIG.  14    the hammer  17  with beveled surface as shown in the example of the  FIG.  13    is shown during firing or after the down-setting of the upper body  31 . 
     In the example of the  FIG.  15    is shown the hammer  17  for a two-stage trigger mechanism comprising the spring-loaded plunger  25 , which functions as the evasive means during down-setting of the body and as turning means for the safety lever  11  of the firing pin safety  10 . 
     In the example of the  FIG.  16    the bolt carrier  12  has been removed from the upper body  31  and the safety lever  11  of the firing pin safety  10  has been turned manually to an extreme position on right i.e. to a dismantle position, in which position the safety lever  11  of the firing pin safety  10  can be dismantled and the firing pin  15  is popping out automatically, because it is spring-loaded, and the firing pin  15  is removed from inside the bolt  18  without tools. 
     In the example of the  FIG.  17    the safety lever  11  of the firing pin safety  10  is dismantled after being turned to the dismantle position for cleaning and/or maintenance and the firing pin  15  has been removed. The spring-loaded return plunger  24  is returning the safety lever  11  automatically to its basic position. The return plunger  24  is mechanically locking the safety lever  11  to the bolt carrier  12 . 
     Thus, the safety lever  11  has three main positions: a basic position, in which position the safety lever  11  retains movement of the firing pin  15  to the primer of the cartridge and from inside the bolt  18 , a release position, in which the safety lever  11  actuated by the hammer  17  releases movement of the firing pin  15  towards the primer of the cartridge but not from inside the bolt  18 , and a dismantle position, in which position the safety lever  11  of the firing pin safety  10  can be dismantled and the firing pin  15  can be removed manually from inside the bolt  18  of the firearm  100  without tools. The safety lever  11  has form-fitting forms that correspond to form-fitting forms of the breech head  16  of the firing pin  15  and thus, by turning the safety lever  11  the positions are provided. The form-fitting forms can be configured of protrusions and/or grooves on the bottom surface of safety lever  11  and around the breech head  16 . In the basic position the firing pin safety  10  must be positioned by the safety lever  11  to a position, in which movement of the safety pin  15  forward seen from the user point of view is prevented. The safety lever  11  also locks the movement of the safety pin  15  towards the user. In the basic position thus, movement of the safety pin  15  forward cannot be caused by force as the movement is prevented by the safety lever  11 . The movement of the hammer  17  turns the safety lever  11  to release position and the safety pin  15  is enabled to move forward. In the dismantle position the safety lever  11  is turned sideways, turned right in the implementation of the figure and the locking of the safety pin  15  is released towards the user and thus the safety pin  15  can be dismantled. 
     In the  FIGS.  18 - 22    is shown an example of the form-fitting forms of the breech head  16  of the firing pin  15  and the safety lever  11  in different positions of the firing pin safety. The breech head  16  of the firing pin  15  comprises first and second shoulders  32 ,  34  and a recess  33  in between the shoulders  32 ,  34 . The safety lever  11  comprises a body  39  provided with two on its outer surface extending inclined grooves  36 ,  37  and a shoulder part  38  formed on the outer surface of the body  39  as well as a bearing surface  42  and two arch recesses, one arch recess  45 A for release and one arch recess for dismantle  45 B. 
     In  FIG.  18    the safety lever  11  in respect to the breech head of the firing pin  15  is in the basic position, when the safety lever  11  retains movement of the firing pin  15  to a primer of a cartridge and from inside the bolt  18 . Thus, movements towards and away from the shooter are prevented. The form-fitting forms configured by the shoulder part  38  of the body  39  of the safety lever  11  and the second protrusion  34  of the breech head  16  of the firing pin  15  are in contact. The body of the safety lever  11  is located partially within the recess  33  between a first shoulder  32  and the second shoulder  34  of the firing pin  15 . 
       FIG.  19    shows the situation in the basic position in case the firing pin  15  is tried to be moved forwards and how the form-fitting forms of the safety lever  11  and the firing pin  15  prevent the movement, as the firing pin  15  rests with the shoulder  32  against a bearing surface  42  of the safety lever  11 . Grooves  36 ,  37  are advantageously provided for dust and/or dirt removal. 
     In  FIG.  20    is shown the release position, in which the safety lever  11  actuated by the hammer  17  releases movement of the firing pin  15  towards the primer of the cartridge but not from inside the bolt  18 . The movement of the hammer  17  has moved the safety lever  11  to the release position, as the bearing surface  42  turns to the side—to the right in the example of the figure—and opens a form-fitting space by the release arch recess  45 A for the first shoulder  32  to move and the firing pin  15  can freely move forwards. 
     In  FIG.  21    is shown the release position, in which the safety lever  11  actuated by the hammer  17  releases movement of the firing pin  15  towards the primer of the cartridge but not from inside the bolt  18 . The movement of the hammer  17  has moved the safety lever  11  to the release position, as the bearing surface  42  turns to side—to right in the example of the figure—and opens a form-fitting space by the release arch recess  45 A for the first shoulder  32  to move and the firing pin  15  can freely move forwards. 
     In  FIG.  22    is shown the dismantle position, in which position the safety lever  11  of the firing pin safety  10  can be dismantled and the firing pin  15  can be removed manually from inside the bolt  18  of the firearm  100  without tools. The safety lever  11  is turned to its rightmost position, which releases the firing pin  15  as the dismantle arch recess  45 B is positioned over the second shoulder  34  of the firing pin  15  and the firing pin  15  moves backwards by itself due to the spring-actuation by the spring  30  from below the body  39  of the safety lever  11  under the dismantle arch recess  45 B. 
     In  FIGS.  23 - 28    is schematically shown another advantageous example of the form-fitting forms of the firing pin safety with safety lever locking means. In this example ball bearing locking means are provided, which comprise a ball  46 , a hole  47  for the ball  46  and a counter sink locking screw  51 . In this example turning the screw  51  drives the ball  46  out in radial direction and secures the safety lever  11  in vertical direction by means of a ball recess  52  in the bolt carrier  12 . The return spring of the firing pin  15  is denoted by reference numeral  30 . The body of the safety lever  11  is provided with the arch recesses  45 A,  45 B for release and dismantle and with the shoulder part  38  as well as a bearing surface  42 . The firing pin  15  comprises the breech head  16  provided with the two shoulders  32 ,  34  and is also provided with a groove  35  for locking the spring  30  by attachment of the last loop of the spring  30  into the groove  35 . By this the return-spring  30  is securely attached to the firing pin  15  preventing accidental loss of the spring  30 . The body  39  of the safety lever  11  is provided with a preferably threaded opening  49  for the screw  51 . The turning movement of the safety lever  11  from the basic position to the release position and back is shown in  FIG.  26    by arch A 1  and from the release position to the dismantle position as indicated by arch A 2 . 
     In  FIGS.  25 - 26    is shown the locking principle of the safety lever  11  in greater detail. In basic position the firing pin  15  is fully secured within the form-fitting forms provided by the shoulder part  38  of the body  39  of the safety lever  11  and the second shoulder  34  of the breech head  16  of the firing pin  15  as well as by the release arch recess  45 A not exceeding the first shoulder  32  prevented by means of the bearing surface  42 , which prevent movements towards back or front and thus the firing pin  15  cannot contact the primer and danger of slam-fire is prevented. 
     In the release position, the firing pin  15  shown in  FIG.  27    can reach the primer once hit by the hammer  17 . The firing pin  15  is still secured inside the bolt carrier  12  by means of the shoulder part  38 . In the dismantle position the manual, tool-less removal of the firing pin  15  is provided. 
     In the  FIG.  28    is shown the safety lever  11  in its dismantle position, in which when the bolt carrier  12  has been removed from the firearm  100 , the safety lever  11  can be manually turned into the dismantle position and the spring-loaded firing pin  15  is being released to the rear. 
     In the description in the foregoing, although some functions and elements have been described with reference to certain features and examples, those functions and elements may be performable by other features and examples whether described or not. Although features have been described with reference to certain embodiments or examples, those features may also be present in other embodiments or examples whether described or not. 
     Above only some advantageous examples of the inventions have been described to which examples the invention is not to be narrowly limited and many modifications and alterations are possible within the invention. 
     REFERENCE SIGNS USED IN THE DRAWING 
       10  firing pin safety 
       11  safety lever 
       12  bolt carrier 
       15  firing pin 
       16  breech head 
       17  hammer 
       18  bolt 
       19  bevel 
       24  spring-loaded return plunger 
       25  spring-loaded plunger 
       26  beveled surface 
       30  spring 
       31  upper body 
       32  shoulder 
       33  recess 
       34  shoulder 
       35  groove for locking the spring 
       36  groove for dust/dirt removal 
       37  groove for dust/dirt removal 
       38  shoulder part 
       39  body 
       42  bearing surface 
       45 A release arc recess 
       45 B dismantle arc recess 
       46  ball 
       47  hole 
       49  opening 
       51  screw 
       52  ball recess 
       100  firearm