Patent Publication Number: US-2023152051-A1

Title: Carbine assembly

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of the earlier U.S. Utility patent application Ser. No. 17/154,930, filed Jan. 21, 2021, which claims priority to U.S. Provisional Patent Application Ser. No. 62/963,952, filed Jan. 21, 2020, the disclosures of which are hereby incorporated entirely herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Technical Field 
     This invention relates generally to a carbine assembly for an AR type rifle and more particularly to a fast cycling/low recoil pistol caliber carbine assembly. 
     State of the Art 
     Carbine assemblies for AR15 style rifles are available for use of pistol caliber ammunition. However, these existing carbine assemblies are lacking their functionality, namely they are not fast cycling/low recoil pistol caliber carbine assemblies. Accordingly, there is a need for fast cycling/low recoil pistol caliber carbine assemblies. 
     DISCLOSURE OF THE INVENTION 
     The present invention relates to a carbine assembly for an AR15 style rifle that is a fast cycling/low recoil pistol caliber carbine assembly. The assembly provides last round bolt hold open, trigger finger actuated bolt release, short stroke cycle, barrel ramp, ambidextrous magazine release, uses Glock magazines and the like. 
     An embodiment includes a carbine assembly comprising: an upper receiver; a lower receiver with a magazine fillable with ammunition removably coupled to the lower receiver; a barrel; a bolt carrier; a buffer; and a bolt stop/feed assembly coupled within the upper receiver and the lower receiver, the bolt stop/feed assembly comprising: a control base; a control spring; a control lever; a bolt stop; and a feed ramp all configured to operate to feed ammunition into the barrel and stop the bolt carrier operation when a last round of ammunition is fired from the carbine assembly. 
     The foregoing and other features and advantages of the present invention will be apparent from the following more detailed description of the particular embodiments of the invention, as illustrated in the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of the present invention may be derived by referring to the detailed description and claims when considered in connection with the Figures, wherein like reference numbers refer to similar items throughout the Figures, and: 
         FIG.  1    is a perspective view of a portion of a carbine assembly in accordance with embodiments; 
         FIG.  2    is a perspective view of a portion of a carbine assembly in accordance with embodiments; 
         FIG.  3    is a perspective view of a portion of a carbine assembly in accordance with embodiments; 
         FIG.  4 A  is a perspective view of an upper receiver of a carbine assembly in accordance with embodiments; 
         FIG.  4 B  is a perspective view of an upper receiver of a carbine assembly in accordance with embodiments; 
         FIG.  5    is another perspective view of an upper receiver of a carbine assembly in accordance with embodiments; 
         FIG.  6    is a perspective view of lower receiver of a carbine assembly in accordance with embodiments; 
         FIG.  7    is a perspective view of a feed ramp of a carbine assembly in accordance with embodiments; 
         FIG.  8    is a perspective view of a bolt stop of a carbine assembly in accordance with embodiments; 
         FIG.  9    is a perspective view of magazine of a carbine assembly in accordance with embodiments; 
         FIG.  10    is a perspective view of control lever of a carbine assembly in accordance with embodiments; 
         FIG.  11 A  is a perspective view of a control base of a carbine assembly in accordance with embodiments; 
         FIG.  11 B  is a perspective view of a control base of a carbine assembly in accordance with embodiments; 
         FIG.  12    is a perspective view of a control pivot pin of a carbine assembly in accordance with embodiments; 
         FIG.  13    is a perspective view of a control spring of a carbine assembly in accordance with embodiments; 
         FIG.  14    is a perspective view of an ejector of a carbine assembly in accordance with embodiments; 
         FIG.  15 A  is a perspective view of gap filling devices of a carbine assembly in accordance with embodiments; 
         FIG.  15 B  is a perspective view of gap filling devices of a carbine assembly in accordance with embodiments; and 
         FIG.  16    is a perspective view of portions of a weapon with the carbine assembly coupled thereto in accordance with embodiments. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     As discussed above, embodiments of the present invention relate a carbine assembly for an AR15 style rifle that is a fast cycling/low recoil pistol caliber carbine assembly. The assembly provides last round bolt hold open, trigger finger actuated bolt release, short stroke cycle, barrel ramp, ambidextrous magazine release, uses Glock magazines and the like. 
     Referring to the drawings,  FIGS.  1 - 16    depict an embodiment of fast cycling/low recoil pistol caliber carbine assembly  100 . Generally, the carbine assembly includes an upper receiver  110 , a lower receiver  120 , a bolt carrier  140 , a buffer  150 , a bolt stop/feed assembly  10 , and an ejector  12 . The bolt stop/feed assembly  10  comprises a control base  20 , a control spring  30 , a control lever  40 , a bolt stop  50 , a feed ramp  60  and a gap filling device  70 . Other components discussed include a magazine  80 . Other components that are internal to the carbine assembly  100 , some shown without numbering and others not shown may include the following: a trigger, a hammer, firing pin, connectors for various components, screws for coupling elements together, a buffer and all buffer components internal to the buffer tube and so forth. 
     The buffer  150 , in embodiments is a longer buffer than that for a .223 caliber ammunition buffer. This longer buffer  150  allows for a short stroke to fire pistol ammunition, such as 9 mm caliber ammunition. The bolt stop/feed assembly  10  operates to provide a bolt stop capability with the longer buffer that is currently not available in conventional carbine assemblies. 
     An embodiment of the upper receiver  110  is depicted in  FIGS.  4 A- 5   . The upper receiver may include clearance cuts  12  for the bolt stop/feed assembly  10  to operate. These cuts for recesses in the upper receiver  110 . The upper receiver  110  may further include screw holes  114  and surface for locating and securing the ejector  12  to the upper receiver  110 . The upper receiver  110  may also include a gap  116  for the control lever  40  to extend through and operate as part of the bolt stop/feed assembly  10 . 
     An embodiment of the lower receiver  120  is depicted in  FIG.  6   . The lower receiver  120  may include a pocket  126  and roll pin holes for locating and securing the feed ramp  60 . There is also a mechanism pocket  122  to house the control base  20 , control lever  40 , control pin  35  and control spring  30 . Additionally, the mechanism pocket  122  includes a threaded hole for securing the control base  20  within the pocket  122 . The lower receiver  120  may also include a gap  124  on each side of the lower receiver for the control lever  40  to extend through and operate as part of the bolt stop/feed assembly  10 . The lower receiver  120  may include aperture  128  for the magazine  80  to extend therethrough. 
     An embodiment of the feed ramp  60  is depicted in  FIG.  7   . The feed ramp may include a cartridge feed ramp surface  64  that extends from a first surface  61  to a second surface  63 , wherein the first surface faces the aperture  128  of the lower receiver  120  when the feed ramp  60  is coupled to the lower receiver  120 . The feed ramp  60  may also include protrusion members  65  extending from each side of the feed ramp surface  64 , each protrusion member  65  having a tapered surface, wherein the feed ramp surface  64  and protrusion members  65  with tapered surfaces operate to direct or otherwise funnel the cartridge  82  (ammunition  82 ) into the barrel  130  (See  FIG.  1   ). The feed ramp  60  also includes bolt stop pivot bosses  66  that locates and provides a pivot point for the bolt stop  50 . The feed ramp  60  also comprises a lower mount boss  62  that inserts into the pocket  126  of the lower receiver  120  to provide a foundation for the feed ramp  60 , and the lower mount boss  62  includes roll pin holes  68 , wherein roll pins extend through the roll pin holes  62  and corresponding holes in the lower receiver  120  to secure the feed ramp  60  in place. The feed ramp  60  is also an important feature because the bolt carrier  140  does not have a cup on the bottom in order to work with the feed ramp  60 , by giving space to not contact the feed ramp  60 . The lack of the cup on the bolt carrier  140  helps with the feeding of the ammunition as well. Further still, the ramp on bolt is removed or reduce in order to cock the hammer. 
     An embodiment of the bolt stop  50  is depicted in  FIG.  8   . The bolt stop  50  may include a body  52  formed in a U-shape with a space  51  between two arms  55 . The bolt stop  50  may include an activation tab  54  extending from one arm  55  that interfaces with the follower  84  in the magazine  80  (see  FIG.  9   ) to push the bolt stop  50  into position to the stop the bolt carrier  140 . While the activation tab  54  is shown located in a particular place on the arm  55 , the activation tab may be located in various places depending on the magazine being used. Or some embodiments may include more than one activation tab  54  to account for various types of magazines without the need for a specific bolt stop  50 . The bolt stop  50  includes bolt stop pivot holes  53  on the end of the arms  55  that mount to the bolt stop pivot bosses  63  of the feed ramp  60 , wherein the bosses  63  extend into the bolt stop pivot holes  53 . The bolt stop  50  may also include a bolt stop tab  56  that, when activated, prevents the forward motion of the bolt carrier  140 , thereby locking it in a rearward position, as shown in  FIG.  2   . The bolt stop  50  also includes control bosses  58  that interfaces with the control lever  40  to activate or deactivate the bolt stop  50 . One boss  58  is for a right-hand configuration and the other boss  58  is for a left-hand configuration. 
     An embodiment of the magazine  80  depicted in  FIG.  9    may include a magazine follower  84  that operates for a bolt stop activation feature. 
     An embodiment of the control lever  40  depicted in  FIG.  10   . The control lever  40  may include a finger pad  42  located at the end of an arm  44  that extends out of the gaps  116  and  124  formed in the upper receiver  110  and the lower receiver  120  respectively to provide a control surface to activate or deactivate the bolt stop  50 . The control lever  40  may further include a pivot hole  46  about which the control lever  40  pivots. Further, the control lever  40  may include a boss interface slot  49  that interfaces with the control bosses  58  on the bolt stop  50  to push the bolt stop  50  up or down. 
     An embodiment of the control base  20  is depicted in  FIGS.  11 A-B . The control base  20  may include a mounting hole  22  for receiving a screw therethrough as a means to secure the control base  20  to the lower receiver  120 , such as in the mechanism pocket  122 . The control base  20  may include a notch  26  to locate and secure the gap filling device  70  wherein a protrusion  76  of the gap filling device  70  is engaged within the notch  26 . The control base  20  may also include a control lever pivot hole  28  that provides a location for the control lever spring  30 . The control base  20  may include a channel  24  for which the control lever  40  extends through the channel  24  and the pivot hole  46  aligns with the control lever pivot hole  28  of the control base  20  by use of the control pin  35 . The control base  20  may also include a clearance notch to provide an area for travel of the unused control boss  58  on the bolt stop  50 . 
     The control pivot pin  35  depicted in  FIG.  12    is a control pivot pin  35  that includes a main locating shaft  37 , a pin head  38  and a spring located boss  39 . The main locating shaft  37  operates to locate position in the control base  20  and provides a shaft for the control lever  40  to pivot on. The pin head  39  is for locating and securing the pin  35  in its location. 
     An embodiment of the control spring  30  is depicted in  FIG.  13   . The control spring  30  may include a coil  32  that may be coupled around the pivot pin  35 . The control spring  30  may also include a control lever engagement member  36  that engages the and pushes the control lever  40  down. The control spring  30  may include a control base engagement member  34  that engages and pushes against the control base. 
     An embodiment of the ejector  12  is depicted in  FIG.  14   . The ejector  12  may include a front surface  13  that impacts the back of the cartridge  82  of the ammunition and kicks it out the firearm. The ejector  12  may also include threaded holes  14  that operate to couple the ejector  12  to the upper receiver  110 . The ejector  12  may also include an angled surface extending from the front surface  13  on a bottom side of the ejector  12  in a direction toward the bottom rear of the ejector  12 . The angled surface is a feature that prevents over insertion of the magazine  80 . 
     An embodiment of the gap filling device  70  is depicted in  FIG.  15   . The gap filling device  70  operates to couple to the lower receiver  120  and fill a gap  124  created in the lower receiver  120  by use of this invention (See  FIGS.  3  and  6   ). The lower receiver  120  has a gap  124  on both sides so the same lower receiver  120  can be used by both right-hand and left-hand shooters, wherein the upper receiver  110  may be specific to a right-handed or lefthanded shooter with the same components shown in  FIGS.  4 A- 5    just mirrored depending on the right-handed or left-handed shooter desirability. The gap filling device  70  fills the gap  124  not being used based on whether the shooter is a right-handed or left-handed shooter. 
     In operation, a shown in  FIGS.  1 - 3   , a magazine  80  may be coupled to the lower receiver and extend through the space  51  of the bolt stop  50 . The bottom slanted surface of the ejector  12  keeps the magazine  80  from extending to far into the lower receiver to ensure that the ammunition  82  is in the proper location to be fired. The carbine assembly may operate to load and the ammunition  82  within the barrel  130  using the feed ramp  60  to ensure that ammunitions  82  is accurately loaded and then shoot the ammunition  82  and recoil to allow the cartridge to be expelled through an opening in the upper receiver  110  by use of the ejector  12 . When the last round of ammunition  82  stored within the magazine  80  is shot and the bolt recoils, the magazine follower  84  extends out from the magazine  80  and engages the activation tab  54  of the bolt stop and rotates the bolt stop body  52  about the bolt stop pivot holes  53  such that the bolt stop tab  56  is lifted to interfere with the bolt carrier  140  from extending over the magazine and stop the bolt carrier  140  from operating. The rotation of the bolt stop body  52  lifts the control bosses  58  of the bolt stop  50  that is engaged with the boss interface slot  49  of the control lever  40  and rotates it about the pivot hole  46 . The shooter operating the carbine assembly  100  may then remove the magazine  80  that is empty and put a new magazine within the carbine assembly  100 . The shooter may then depress the finger pad  42 , wherein depressing the finger pad  42  allow the boss interface slot  49  to move down and rotate the bolt stop body  52  about the pivot holes  53  by engaging with the control bosses  58 . This rotates the bolt stop tab  56  out of the way from the bolt and the carbine assembly  100  may operate to shoot ammunition  82  again. 
     The embodiments and examples set forth herein were presented in order to best explain the present invention and its practical application and to thereby enable those of ordinary skill in the art to make and use the invention. However, those of ordinary skill in the art will recognize that the foregoing description and examples have been presented for the purposes of illustration and example only. The description as set forth is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the teachings above without departing from the spirit and scope of the forthcoming claims.