Patent Publication Number: US-11662168-B2

Title: Breech block and gun

Description:
This nonprovisional application is a continuation of International Application No. PCT/EP2020/070781, which was filed on Jul. 23, 2020, and which claims priority to German Patent Application No. 10 2019 122 296.6, which was filed in Germany on Aug. 20, 2019, and which are both herein incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a breech block, preferably a gun barrel breech, in particular wedge breech block, having a breech end and a breech wedge, preferably for a large-caliber gun, comprising an opener shaft with a rotationally coupled opening lever and an ejector system for pulling out cartridge cases or cartridge bases from the breech block, said ejector system comprising at least one ejector and at least one ejector lever, which actuates the ejector. 
     Furthermore, the invention relates to a gun having such a breech block. 
     Description of the Background Art 
     DE 10 2004 052 550 A1, which is incorporated herein by reference, discloses a wedge breech block for a gun. The wedge breech block has a breech wedge that can be opened downwards perpendicular to the bore axis of the gun barrel. 
     DE 198 43 294 C2, which corresponds to U.S. Pat. No. 6,260,297, which is incorporated herein by reference, discloses a large-caliber firearm having a gun barrel and a breech end attached to it on the breech side. Attached to the breech end is a catch and ejection device for fixing and pulling out rimless cartridge cases which is longitudinally movably arranged and has an ejector which is pivotable against the pressure of a compression spring. 
     DE 41 33 618 C2, which corresponds to U.S. Pat. No. 5,307,724, which is incorporated herein by reference, shows an ejector system for barrel weapons that has a linearly slidable ejector that is operated via an ejector lever. The ejector lever is in turn operated via a control cam arranged on the breech wedge. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a breech block that has an improved ejector system. 
     According to an example of the invention, a breech block, in particular wedge breech block, having a breech end and a breech wedge is provided, comprising an opener shaft with a rotationally coupled opening lever and an ejector system for pulling out cartridge cases or cartridge bases from the breech block, said ejector system comprising at least one ejector and at least one ejector lever, which actuates the ejector, wherein the ejector lever is rotationally movably mounted on the opener shaft and the ejector system comprises at least one transmission element that transmits a rotational movement of the opening lever to the ejector lever. 
     Further, according to the invention, a gun is provided which comprises at least one such breech block or one further developed as described below. 
     The gun is a barrel gun with a recoiling mass, which comprises at least one gun barrel and the breech block. 
     The wedge breech block is in particular a vertical wedge breech block having a breech wedge that is movable transversely to the bore axis of the gun barrel between a closed and an open position. 
     Furthermore, the breech block comprises a breech block mechanism by means of which the breech block can be opened and closed. 
     The opener shaft and the opening lever which is rotationally coupled to the opener shaft are used to move the breech wedge between an open and a closed position. The opener shaft is driven by the breech block mechanism. 
     The at least one ejector lever is rotationally mounted on the opener shaft. A rotational movement of the opener shaft is not transmitted directly to the ejector lever, but instead the rotational movement of the opener shaft is transmitted to the ejector lever via the transmission element. 
     The ejector lever operates the ejector, which in turn ejects the cartridge case or the cartridge base. 
     According to the invention, a breech block with a small ejector system is created, which makes it possible that a direct contact between opening lever and ejector lever is avoided. According to the invention, the rotational movement of the opening lever is first transmitted to the transmission element, which in turn transmits the rotational movement to the ejector lever. This prevents a direct impact or shock-like actuation of the ejector lever by the opening lever. As a result, less wear of the opening lever and ejector lever is ensured and thus an improved service life is achieved. 
     The transmission element can be mounted on a first axis, which is spaced from the opener shaft. 
     This ensures that the rotational movement of the opening lever does not have to be transmitted directly to the ejector lever, but instead that the transmission element is arranged as an intermediate element between the ejector lever and the opening lever and can transmit or reduce the rotational movement of the opening lever to the ejector lever. 
     Another advantage is that the transmission element can be changed independently of the opener shaft and the ejector lever due to the bearing on the first axis and a simple assembly or disassembly of the transmission element is guaranteed. 
     The ejector system can have at least one first contact roller arranged at the end of the transmission element for contact with the opening lever and at least has a second contact roller arranged at the first end of the transmission element for contact with the at least one ejector lever. 
     This ensures that an unrolling takes place between the contact rollers of the transmission element and the respective lever that is contacted. Friction losses between the opening lever and the first contact roller, as well as between the ejector lever and the second contact roller are thus avoided. This leads to a lower wear and an increased service life of the ejector system of the breech block according to the invention. 
     A first contact roller per opening lever and a second contact roller per ejector lever can be formed. 
     The at least one first contact roller and at least one second contact roller can be arranged on a common second axis. 
     The ejector system can have at least one preload element that the transmission element preloads against the at least one ejector lever. 
     As a result, the transmission element and ejector lever are in contact with each other at all times, thus also with the case base. When an ejector movement initiates and the ejectors are actuated, these are already in contact with the cartridge case base that is to be ejected. 
     The preload element can be designed, for example, as a spring, or as a spring damper system. 
     The at least one ejector lever can have a lever arm with an arc-shaped contact surface, which is permanently in contact with the at least one second contact roller. 
     This achieves that the rotational movement of the opening lever is not transmitted linearly to the ejector lever, but instead that the angle of rotation of the rotational movement of the ejection lever describes a degressive or a progressive characteristic curve in relation to the angle of rotation of the rotational movement of the opening lever. Accordingly, the ejector describes a corresponding degressive or progressive characteristic curve with regard to the forward movement. Thus, the shape of the arc-shaped contact surface can predetermine the movement characteristics of the ejector. The movement characteristics of the ejector can also be adjusted by changing the ejector lever. 
     Thus, the contact changes in the direction of the ejector/the opener shaft axis. If the angular velocity of the opening lever remains the same, the transmission behavior changes. 
     Furthermore, it may be provided that the contact surface can be essentially concave, so that when opening the breech block, the rotation angle of the rotational movement of the ejector lever in relation to the rotation angle of the rotational movement of the opening lever describes a progressive characteristic curve. 
     The progressive characteristic curve ensures that a cartridge base or cartridge to be ejected is continuously accelerated throughout the ejection process, so that a safe ejection of the cartridge or the cartridge base is ensured. 
     The opening lever can be formed in such a way that it is not in contact with the first contact roller in the open position of the breech block and the first contact roller can be brought into contact with the opening lever in the course of the opening process. 
     This ensures that there is no permanent contact between the opening lever and the ejector lever, so that a preload between these elements is avoided. This prevents the preload elements of the ejector system from wearing out. 
     Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes, combinations, and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein: 
         FIG.  1    is a schematic perspective view of the inventive breech block having an ejector system; 
         FIG.  2    is a schematic perspective enlarged view of the breech block having the ejector system from  FIG.  1   ; 
         FIG.  3   a    is a schematic side view of the ejector system of the inventive breech block, wherein the breech wedge is in a closed position; 
         FIG.  3   b    is a schematic side view of the ejector system of the inventive breech block according to  FIG.  3   a   , wherein the breech wedge is in the open position; 
         FIG.  4    is a schematic diagram of the angle of the opening lever and the angle of the ejector lever in relation to the forward movement; and 
         FIG.  5    is a schematic rear view of the breech block. 
     
    
    
     DETAILED DESCRIPTION 
       FIG.  1    shows a schematic perspective view of the breech block  10  according to the invention having an ejector system  30 . The breech block  10  is preferably a gun barrel breech, in particular a wedge breech block having a breech end  12  and a breech wedge  14 . 
     The breech block is part of a gun (not shown). 
     The breech block  10  also has an opener shaft  20  with a rotationally coupled opening lever  22 . The opener shaft  20  is mounted at the bottom of the breech end  12  by means of several opener shaft bearings  24 . 
     Furthermore, the opener shaft  20  has a cog wheel, via which the opener shaft  20  can be driven. 
     The breech block  10  also has an ejector system  30  for pulling out cartridge cases or cartridge bases from the breech block  10 . The ejector system  30  comprises at least one ejector  32  and at least one ejector lever  34 , which actuates the ejector  32 . 
     The ejector lever  34  is rotationally movably mounted on the opener shaft  22  and the ejector system has at least one transmission element  40 , which transmits a rotational movement of the opening lever  22  to the ejector lever  34 . 
       FIG.  2    shows a schematic perspective enlarged view of the breech block having the ejector system  30  from  FIG.  1   . As can be seen more clearly from  FIG.  2   , the transmission element  40  is mounted on a first axis  43 , which is spaced from the opener shaft  20 . The first axis  43  is attached to the underside of the breech end  12  with appropriate bearings, which support the axis  43 . 
     At one end  41   a  of the transmission element  40  at least a first contact roller  42  is arranged for contact with the opening lever  22 . Furthermore, at least a second contact roller  44  for contact with the at least one ejector lever  34  is arranged at the first end  41   a  of the transmission element  40 . 
     The at least one first contact roll  42  and the at least one second contact roll  44  are arranged on a common second axis  46 . 
     The ejector system  30  has at least one preload element  50  that the transmission element  40  preloads against the at least one ejector lever  34 . According to the embodiment, the preload element  50  is a spring arranged at a second end  41   b  of the transmission element  40 . 
     As shown in  FIG.  1    and  FIG.  2   , the transmission element  40  is embodied as a lever. As can be seen in  FIG.  3   a   , the first end  41   a  has two fork-like protrusions on which the axis  46  is arranged. The second end  41   b  is arranged on the opposite side of the transmission element  40  and angled to the first end  41   a.    
     In  FIG.  1    and  FIG.  2    it can be seen that two ejector levers  34  are formed, for each of which a second contact roller  34  is formed. 
       FIG.  3   a    shows a schematic side view of the ejector system  30  of the inventive breech block  10 , wherein the breech wedge  14  is in a closed position.  FIG.  3   b    shows a schematic side view of the ejector system  30  of the inventive breech block  10  according to  FIG.  3   a   , wherein the breech wedge  14  is in the open position. 
     The at least one ejector lever  34  has a first lever arm  36  with an arc-shaped contact surface  38 , which is permanently in contact with the at least one second contact roller  44 . 
     Furthermore, the ejector lever  34  has a second lever arm  38 , as can be seen in  FIG.  1   . The second lever arm  38  is used to operate the ejector  32 . 
     The contact surface  38  of the first lever arm  36  is essentially concave, so that when opening the breech block  10 , the rotation angle of the rotational movement of the ejector lever  34  in relation to the rotation angle of the rotational movement of the opening lever  22  describes a progressive characteristic curve. 
     The opening lever  22  is designed in such a way that it is not in contact with the first contact roller  42  in the open position of the breech block  10  and the first contact roller  42  can be brought into contact with the opening lever  22  in the course of the opening process. 
     As can be seen in  FIG.  3   a    and  FIG.  3   b   , the opening lever  22  has a protrusion with a contact surface  23  which can be brought into contact with the first contact roller  42 . The contact surface  23  of the opening lever  22  is essentially flat. 
       FIG.  4    shows a schematic diagram of the rotation angle of the opening lever  22  and the rotation angle of the ejector lever  34  in relation to the forward movement. The diagram shows that in relation to the forward movement, the angle of rotation of the opener shaft  20  changes linearly and the angle of rotation of the ejector  32  describes a progressive characteristic curve. 
       FIG.  5    shows a schematic rear view of the breech block  10  according to the invention in an open position with open cartridge bearing  11 . The breech wedge  14  is in the open position and the ejector  32  is clearly visible. The view shown in  FIG.  5    shows the ejector  32  after ejection of a cartridge base or a cartridge case. 
     The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.