Abstract:
A two piece ejection system for a shotgun includes a chamber portion having a first, second and third section of varying outside diameters and an extractor formed from a hollow cylindrical tube having a first and second end, the second end including a plurality of slots. The slots are configured to allow the extractor to slide over the circumference of the third section of the chamber portion and be in sliding engagement with the second section of the chamber portion. Interference means on the plurality of slots and the sections of the chamber portion restrict the travel of the extractor over the second section of the chamber portion.

Description:
TECHNICAL FIELD  
       [0001]     The invention relates to break-open firearms having one or more barrels and more particularly to the ejectors for such guns, wherein the ejectors eject spent cartridges from the barrels when the barrels are moved from their closed position to their open position.  
       BACKGROUND OF THE INVENTION  
       [0002]     Broadly, the term “break-open firearm” includes all firearms that have one or more barrels pivotally mounted on the frame of the firearm. The barrel or barrels are rotatable from their closed and locked ready-to-fire position to their open loading-and-unloading position, as required by the shooter. Such firearms are normally designed so that they can be disassembled into two or more parts or sub-assemblies (for example, a barrel sub-assembly and a stock sub-assembly) for convenience in cleaning, storing and transporting the firearm, and they include single and double barreled rifles and shotguns and combinations thereof (including both side-by-side and over-and-under type).  
         [0003]     In break-open firearms of the type to which the present invention relates the barrel or barrels are mounted on a barrel housing (also known as a monoblock) that is pivotally mounted on the frame of the firearm, the barrel housing being formed with one or more longitudinally extending barrel receiving bores in which the rearward ends of the barrels are received and to which they are secured. The barrel housing also includes a longitudinally movable ejector adapted to eject a spent cartridge from one of the barrels when the barrels and barrel housing are rotated from their closed position to their open loading-and-unloading position. Various cartridge case ejectors are described in U.S. Pat. Nos. 3,715,825; 3,984,933; 5,109,621; 5,459,956; and 6,839,997.  
         [0004]     Currently, the most commonly employed ejectors having ejector receiving slots on the outside surface of the chamber portion of a barrel, with matching dovetail-shaped transverse cross-sections on the ejector. A close and smoothly functioning fit of all moving or mating parts is an extremely important feature and the cavity geometry of the ejector chamber controls the throw of the ejector when it is assembled. It is difficult, exacting and time consuming to obtain the close fit and smooth functioning required of the matching dovetail surfaces of the ejectors and ejector receiving slots of conventional break-open firearms. By way of example, in order to minimize lateral play of the dovetailed ejector within the dovetailed ejector receiving slots, it is necessary to fit the facing dovetailed surfaces of these parts together with a clearance of about 0.0005 inch. As a result, considerable effort has heretofore been expended in an attempt to devise other means for retaining ejectors in the ejector receiving slots of the barrel housing that would be less difficult to fabricate than the required smooth fit and small tolerances than are in the conventional dovetailed parts.  
         [0005]     A need exists for an ejector that requires minimal milling and reduced manufacturing costs.  
         [0006]     A further need exists for an ejector system that will enhance the ejection characteristics of pulling the spent cartridge from the ejector as the barrel or barrels are rotated from their closed and locked ready-to-fire position to their open loading-and-unloading position.  
         [0007]     A still further need exists for a two piece ejection system that separates the chamber geometry from the rim recess geometry.  
       BRIEF SUMMARY OF THE INVENTION  
       [0008]     The present invention is directed to a monolithic ejection system for break open firearms. The inventive ejection system comprises a two piece ejection system that includes a chamber portion having a first, second and third section of varying outside diameters and an extractor formed from a hollow cylindrical tube having a first and second end, the second end including a plurality of slots. The slots are configured to allow the extractor to slide over the circumference of the third section of the chamber portion and be in sliding engagement with the second section of the chamber portion. Interference means on the plurality of slots and the sections of the chamber portion restrict the travel of the extractor over the second section of the chamber portion.  
         [0009]     The first section has a diameter A, the second section has a diameter B and the third section has a diameter C in which the diameter B is smaller than diameter A and diameter C is larger than diameter B but smaller than diameter A.  
         [0010]     The interference means is comprised of an interior expanded portion on each of the plurality of slots and a ledge formed at the intersection of the second and third sections of the chamber portion.  
         [0011]     The first end of the extractor includes a U-shaped cutout and a rim around the circumference of the first end.  
         [0012]     The present invention is further directed to an ejection system that includes a chamber portion having a plurality of sections with varying outside diameters and an extractor formed from a hollow cylindrical tube having a first and second end. The second end includes a plurality of slots configured to allow the extractor to slide over the circumference of at least one of the chamber sections of varying outside diameters. When assembled, the two piece ejection system provides for movement of the extractor from a closed position to a full throw position.  
         [0013]     The plurality of sections include a first section having a diameter A, a second section having a diameter B and a third section having a diameter C, wherein diameter B is smaller than diameter A and diameter C is larger than diameter B but smaller than diameter A.  
         [0014]     The interference means on the plurality of slots and the sections of the chamber portion restrict the travel of the extractor over a selected section of the chamber portion. The interference means is comprised of an interior expanded portion on each of the plurality of slots and a ledge formed at intersections of the sections of the chamber portion.  
         [0015]     The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]     For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:  
         [0017]      FIG. 1  is a side plan view of an over- and-under shotgun;  
         [0018]      FIG. 2  is a is a side plan view of the shotgun of  FIG. 1  illustrating the open position in shadow;  
         [0019]      FIG. 3  is a partial plan view of a portion of the shotgun of  FIG. 2  in the in the open position;  
         [0020]      FIG. 4  is a side plan view of a prior art ejection system;  
         [0021]      FIG. 5  is a side plan view of the ejection system of  FIG. 4  illustrating the extraction portion of the prior art ejection system;  
         [0022]      FIG. 6  is a side plan view of the inventive two piece ejection system;  
         [0023]      FIG. 7  is a cut-away view of the assembled ejection system of  FIG. 10 ;  
         [0024]      FIG. 8  is an enlarged cross sectional view of detail  8  of  FIG. 7  illustrating the interference fit between the two pieces of the injection system;  
         [0025]      FIG. 9  is a side plan view of the assembled ejection system of  FIG. 6  in a closed position;  
         [0026]      FIG. 10  is a side plan view of the assembled ejection system of  FIG. 6  in a full throw position;  
         [0027]      FIG. 11  is a perspective view of the extraction piece of the ejection system; and  
         [0028]      FIG. 12  is a perspective view of the chamber piece of the ejection system;  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0029]     The present invention relates to break-open firearms of the type in which the barrel or barrels of the firearm are mounted on a barrel housing that is pivotally secured to the frame of the firearm, the barrel and barrel housing being rotatable from their closed ready-to-fire position to their open loading-and-unloading position. The improved monolithic ejector system of the invention will be described in conjunction with the over-and-under shotgun shown in the drawings but is not limited to this particular firearm.  
         [0030]     As shown best in  FIGS. 1-3 , the over-and-under shotgun  10  embodying the invention has a stock  12 , a frame  14  mounted on the stock  12 , an upper barrel  16 , a lower barrel  18 , a monoblock or barrel housing  20  and a forearm stock  22 . The barrel housing  20  is formed with an upper barrel receiving bore  24  and with a lower barrel receiving bore  26  (shown best in  FIG. 3 ) in which the chamber portion of the upper and lower barrels  16 ,  18  are received and to which they are secured. The forearm stock  22  is releasably secured to the underside of the lower barrel  18  by a forearm latch (not shown), the barrel housing  20  and forearm stock  22  being pivotally mounted on the frame  14  so that the barrels can be rotated from their closed positions as shown in  FIG. 1  to their open position as shown in  FIG. 2 .  
         [0031]     In a prior art dovetailed ejector system  30  illustrated in  FIGS. 4 and 5 , an ejector  32  is mounted in a pair of slots  34 , ( 36  not shown) milled in a chamber portion  28  of a barrel. An annular shoulder  38  includes sections  38 A and  38 B, in which the section  38 B travels with the ejector  32  and section  38 A is a rigid portion integrally formed with the chamber portion  28 . This ejector system  30  requires precision milling on both the ejector  32  and the chamber portion  28 , and the rim recess geometry is dependent on the chamber geometry. Further, in the prior art ejector system  30 , the spent cartridge is pulled from only one small section (typically 120°) of the circular ejector  32 .  
         [0032]     The inventive ejection system  40  comprises a chamber portion  42  of barrels  16 ,  18  and a separate extractor  44  as illustrated in  FIGS. 6-12 . When the barrels and barrel housing in a break-open firearm are rotated from their closed position to their open loading-and-unloading position, the longitudinally movable ejector ejects a spent cartridge from one of the barrels  16 ,  18 . The maximum length of travel of the extractor is called its full throw. This travel is restricted by the chamber&#39;s outer surface geometry interfering the extractor&#39;s inner surface geometry.  
         [0033]     The interior surface of chamber  42  is uninterrupted, whereas the outer surface  46  of chamber  42  has sections of reduced diameter ( FIGS. 6, 10 ,  12 ). The outer surface  46  of chamber  42  has a first section  48  having a first diameter A that is generally the outer diameter of the barrels  16 ,  18 . A second section  50  is adjacent first section  48  and has a second diameter B that is smaller than the diameter A of section  48 . A third section  52  is adjacent second section  50  and has a diameter C that is slightly larger than the diameter B of second section  50  but smaller than the diameter A of section  48 . The intersection of section  48  and section  50  form a first ledge  54  and the intersection of section  50  and section  52  form a second ledge  56  ( FIGS. 6, 7 ,  12 ).  
         [0034]     The extractor  44  is a hollow cylindrical tube having first and second ends  58 ,  60  respectively. The first end  58  includes a rim  62  positioned around the circumference of the first end  58 . Rim  62  also includes a generally U-shaped cutout  64  ( FIGS. 6, 7 ,  10 ,  11 ). The U-shaped cutout  64  is provided for shooters who desire to reload spent shells and for the extraction of an unfired shell.  
         [0035]     The second end  60  includes a plurality of slots  66  placed equal-distant around the circumference of the second end  60  ( FIGS. 6, 8 ,  10 ). The number of slots  66  is generally at least four, preferably between four to eight, but can be even more depending upon the diameter of the chamber  42 . The slots  66  extend at least one half to one third of the distance of the extractor  44 . The slots  66  are for the purpose of assembling the extractor  44  and chamber  42  to form the ejection system  40 . Slots  66  allow expansion of the second end  60  of extractor  44  so that is can be slid over chamber section  52  until it matches up with chamber section  50 . The lower interior portion  68  of each slot  66  includes an expanded portion  70  that is configured to engage the second ledge  56  of the chamber  42  when the extractor  44  is in the full throw position ( FIG. 10 ). In the closed position, the second end  60  of the extractor  44  is adjacent to and buts up against the first ledge  54  of chamber  42  ( FIG. 9 ).  
         [0036]     The length of the extractor  44  can be generally from 2 inches to 0.8 inches and the diameter will depend upon the diameter of the chamber  42 . The length of the slots  66  can range from about 1.5 inches to 0.375 inches. The extractor  44  can be sized to accommodate any gauge shell and can be configured for a variety of rifles.  
         [0037]     The inventive ejection system  40  provides a number of advantages. First, the two piece ejection system separates the chamber geometry from the rim recess geometry wherein the rim recess geometry now becomes the extractor for the spent cartridges. This allows for more flexibility in manufacturing the ejection system. Second, the inventive ejection system  40  requires little milling on the extractor  44  and no milling on the chamber  42 . Third, with the extractor  44  of the present invention, the spent cartridge is pulled from almost all of the circumference of the rim  62  of the cylindrical ejector  44 .  
         [0038]     The ejection system can be constructed from material well know to one skilled in the art of rifle manufacturing.  
         [0039]     Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.