Abstract:
A grenade launcher includes a frame, a barrel mounted on the frame and an opening mechanism. The opening mechanism includes a guide which enables advancement of barrel in a longitudinal direction of the frame and swiveling of the barrel laterally in the final phase of its longitudinal movement.

Description:
FIELD OF THE INVENTION 
     The invention relates generally to grenade launchers. 
     BACKGROUND OF THE INVENTION 
     In a general manner, a grenade launcher comprises a frame with a percussion mechanism activated by a trigger; a barrel mounted on the frame; a locking mechanism for locking and unlocking the barrel in relation to the frame; an opening mechanism which makes it possible to open the grenade launcher so as to load and extract the ammunition; a handguard to hold the grenade launcher and to simultaneously activate said locking and opening mechanisms. 
     Generally, a grenade launcher also comprises an extraction device which enables the automatic extraction of a non-fired grenade or the case of a fired grenade out of the barrel chamber. 
     A grenade launcher of the type having a longitudinal opening with an opening mechanism by means of a movement of the barrel in the longitudinal direction of the grenade launcher is already known. 
     For this type of grenade launcher, the locking mechanism and the automatic extraction mechanism often have a relatively simple design and use. 
     Indeed, the automatic extraction mechanism may form a whole with the bolt face of the frame, whereas the locking mechanism may consist of a bayonet catch which is activated by the simple axial rotation of the barrel which is controlled for example by a simple longitudinal movement of the handguard. 
     In this case, the barrel is simply provided with locking lugs which fit in the front face of the frame of the grenade launcher. By rotating the barrel, the locking lugs are disengaged from the front face. 
     A disadvantage of a grenade launcher of the type with a longitudinal opening is that the choice of the ammunition is restricted, as the length of the grenades to be used is limited to more or less the opening distance of the grenade launcher. 
     A grenade launcher of the type having a lateral opening with a barrel that swivels laterally is already known as well. 
     This type of grenade launcher is advantageous in that longer ammunition can be used without being restricted by the opening distance of the grenade launcher, since the ammunition can be laterally loaded and extracted. 
     However, this type of grenade launcher is disadvantageous in that it has a complex design, due to the complexity of the locking mechanism, such that heavier embodiments are required, and due to the complexity of the specific extraction mechanisms for the case, which is so inconvenient that certain designers abandon an automatic extraction and settle for a manual extraction. 
     The invention aims to remedy one or several of the above-mentioned and other disadvantages and to provide a grenade launcher with a simple design which also makes it possible to use ammunition of any length whatsoever. 
     SUMMARY OF THE INVENTION 
     This aim is reached according to the invention with an improved grenade launcher which comprises a frame, a barrel mounted on the frame and an opening mechanism, characterised in that the opening mechanism comprises guiding means which make it possible to advance the barrel in the longitudinal direction of the frame and to make it swivel laterally in the final phase of its longitudinal movement. 
     In this manner, the ammunition can be laterally loaded in and extracted from the grenade launcher, which makes it possible to use ammunition of any length whatsoever. 
     Likewise, a grenade launcher according to the invention is characterised by an opening which is longitudinal in the first phase of the opening movement, which makes it possible to use opening mechanisms and locking mechanisms with a simple design. 
     The guiding means are preferably such that they make it possible to simultaneously advance and swivel the barrel in said final phase of the longitudinal movement of the barrel. 
     This allows for a faster complete opening movement. According to a preferred, relatively simple embodiment, the barrel is mounted in a handguard which comprises at least two sliding blocks which are mounted one after the other in the longitudinal direction of the handguard and which are mounted in a sliding manner between two longitudinal sliding guides parallel to the frame, one sliding block of which is mounted fixed to the handguard, whereas the other sliding block is mounted such that it can swivel in the lateral direction of the handguard. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For clarity&#39;s sake, an example of an embodiment of an improved grenade launcher according to the invention is described hereafter by way of example only and without being limitative in any way, with reference to the accompanying drawings, in which: 
         FIG. 1  is a schematic view of an improved grenade launcher according to the invention; 
         FIG. 2  shows the part indicated by F 2  in  FIG. 1  in perspective; 
         FIG. 3  is a cross section according to line III-III of  FIG. 1 ; 
         FIGS. 4 and 5  are views similar to those in  FIG. 3 , but in other positions; 
         FIGS. 6 and 7  are exploded views of the parts indicated by F 6  and F 7  respectively in  FIG. 2 ; 
         FIGS. 8 and 9  are sections according to line VIII-VIII and IX-IX respectively of  FIG. 1 ; 
         FIG. 10  is a section according to line X-X in  FIG. 9 ; 
         FIG. 11  is a view similar to that in  FIG. 1 , but for a partially opened position of the grenade launcher; 
         FIG. 12  is a section according to line XII-XII of  FIG. 11 ; 
         FIG. 13  is a section as that in  FIG. 10 , but for a position corresponding to  FIG. 11 ; 
         FIGS. 14 and 16  are views similar to those in  FIG. 11 , but for larger openings and after the ammunition has been ejected; 
         FIGS. 15 and 17  are sections as those in  FIG. 12 , but for the positions of  FIGS. 13 and 15  respectively; 
         FIG. 18  is a section as that of  FIG. 10 , but with non-fired ammunition. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The improved grenade launcher  1  according to the invention as represented in the figures comprises a frame  2 ; a tubular handguard  3  mounted on the frame  2  and a barrel  4  held in a rotating and sliding manner in the handguard  3 . 
     The frame  2  comprises a trigger housing  5  and a bolt  6  in which one extremity of the barrel  4  fits when the grenade launcher  1  is closed and whose front face  7  may support the ammunition which is loaded in the chamber  8  formed in the inserted extremity of the barrel  4 . 
     A percussion mechanism  9  is incorporated in the frame  2  and comprises a firing pin  10  situated in a housing  11  in the front face  7  of the bolt  6 . 
     The percussion mechanism  9  is controlled by a trigger  12 . 
     The barrel  4  is fixed to the frame  2  by means of the handguard  3  which is suspended to the frame  2  in a sliding manner by means of two sliding blocks  13  and  14  which are mounted one after the other in the longitudinal direction X-X′ of the handguard  3  and which are each inserted with edges  15  and  16  respectively in two parallel, longitudinal sliding guides in the form of two grooves  17  in the frame  2 . 
     The sliding block  13  which is closest to the muzzle  18  of the barrel  4  is fixed to the handguard  3 , whereas the other sliding block  14  which is farthest from the muzzle  18  of the barrel  4  is mounted in a laterally revolving manner on the handguard  3  by means of a central pivot  19 . 
     As represented in  FIG. 6 , the revolving sliding block  14  is formed of two semi-circular pieces  20  which are assembled by means of screw bolts  21 . 
     Each extremity of the revolving sliding block  14  is provided with a cavity forming a protrusion on each side which can work in conjunction with a centre swivel stop,  22  and  23  respectively, whereby each of the stops is situated in a cavity  20  and restricts the revolving course of the sliding block  14  round an average position as represented in  FIG. 2 , in which the sliding block  14  is longitudinally directed in relation to the longitudinal direction X-X′ of the handguard  3  and between two extreme swivel positions as represented in  FIGS. 4 and 5 . 
     The fixed sliding block  13  comprises a straight part  24  which is situated at a distance from the revolving sliding block  14 , as well as a part  25  formed of a narrowing conical extremity which extends in the longitudinal direction X-X′ of the handguard towards the revolving sliding block  14 . 
     The centre swivel stop  22  is formed of an extension of the conical part  25  of the fixed sliding block  13 . 
     The handguard  3  is provided with a longitudinal end stop  26  which can work in conjunction with a corresponding end stop on the frame  2 . 
     Both longitudinal end stops  26  and  27  are placed such that, when the grenade launcher is maximally opened in the longitudinal direction, the revolving sliding block  14  is still guided by the sliding guides  17  of the frame  2 , whereas the straight part  24  of the fixed sliding block  13  protrudes entirely over the length of the sliding guides  17  and the conical part  25  of the fixed sliding block  13  protrudes over a certain distance of the length of said sliding guides  17 . 
     To this end, the longitudinal end stops  26  and  27  are placed on the pivot  19  of the handguard  3  and at the front extremity of the frame  2  respectively. 
     In this case, the stop  27  can be withdrawn or raised so as to dismount the handguard  3  from the frame  2 . 
     The barrel  4  is mounted in the handguard  3  in a sliding and rotating manner. 
     An annular stop  28  at the muzzle  18  of the barrel  4  restricts the relative longitudinal movement of the barrel  4  in the handguard  3 . 
     At the opposite extremity of the muzzle  18 , the barrel  4  is provided with a bayonet catch  29 , formed of lugs  30  which can fit as said extremity of the barrel  4  is inserted in the bolt  6 , followed by a rotation of the barrel  4  so as to close the chamber  8  of the barrel  4  and to lock the barrel  4  on the frame  2 . 
     The grenade launcher  1  is provided with means  31  which allow for an automatic control of the axial rotation of the barrel  4  by means of a longitudinal movement of the handguard  3  so as to be able to lock and unlock the barrel  4  when the handguard  3  is moved over a certain distance in the longitudinal direction in relation to the frame  2 . 
     In the example given in the figures, said means  31  are formed of a wedge going through the wall of the handguard  3  so as to form a protuberance  32  of the handguard  3  which is guided in a slanting groove  33  inside the barrel  4 , whereby the groove  33  forms an angle with the longitudinal direction X-X′. 
     The barrel  4  is equipped with a brake  34  in the form of a tilting element which, thanks to the action of the spring  35 , exerts a light radial force on the case of a grenade which may be present in the chamber  8  of the barrel  4 , so that the case will be lightly held up in the chamber  8  when the grenade launcher is opened. 
     In order to secure the position of the axial rotation of the barrel  4  after it has been unlocked, a barrel plunger  36  is mounted in the handguard  3 , whereby the plunger  36  is controlled by a spring  37  retained by a pin  37 ′. 
     Optionally, the grenade launcher  1  can be provided with an automatic extraction device for the ammunition with an extractor  38  in the form of a revolving hook which is mounted in the seat  6  of the frame  2 . 
     The extractor  38  is controlled by a spring  39  which catches the collar of the case of a grenade present in the chamber  8  of the barrel  4 , so that the case can be held against the face  7  of the bolt  6  when the grenade launcher  1  is opened. 
     The extractor  38  is provided with a lever  40  which makes it possible to make the extractor  38  swivel against the action of the spring  39 , so that the extractor  38  can be made inactive. 
     In the same manner, the grenade launcher  1  can be provided with an ejector  41  mounted in the front face  7  of the bolt  6  and controlled by a spring  42  so as to exert an axial force on the case of the grenade. 
     The working and use of the grenade launcher  1  according to the invention are simple and as follows. 
       FIGS. 1 ,  9  and  10  represent the grenade launcher  1  in its closed position after a grenade has been fired and an empty case  3  is situated in the chamber  8  of the barrel  4 , maintained against the front face  7  by the extractor  38 . 
     In order to open the grenade launcher  1 , the user activates the unlocking key  44  of the handguard  3  in relation to the barrel  4  and pushes the handguard  3  forward, which, in the first few millimeters, makes the barrel  4  rotate round its axis, guided by the protuberance  32  of the handguard  3  in the slanting groove  33  of the barrel  4 , such that the barrel  4  is unlocked as the lugs  30  are released from the bolt  6 . 
     Next, thanks to the presence of the stop  28  at the muzzle  18  of the barrel  4 , the longitudinal movement of the handguard  3  also causes the barrel  4  to move longitudinally, while its axial orientation is preserved. 
     During said movement of the barrel  4 , the case  43  is being retained against the front face  7  and it is ejected downward as soon as it has entirely left the chamber  8  through the effect of the ejector  41  as represented in  FIGS. 11 and 13 . 
     During said movement, the handguard  3  is forced to follow a longitudinal trajectory, as the two sliding blocks of the handguard  3  are guided in the sliding guides  17  of the frame  2 . 
     As of the position represented in  FIGS. 11 and 13 , the fixed sliding block  13  leaves the sliding guides  17  as shown in  FIG. 12  and thus makes it possible for the handguard  3  and the barrel  4  to laterally swivel round the pivot  19  as a result of the revolving motion of the sliding block  14 . 
     As represented in  FIGS. 14 and 15 , the lateral rotation is restricted in that the conical part  25  of the fixed sliding block  13  comes to a stop against the front extremity of one of the sliding guides  17 , depending on whether the handguard  3  swivels to the left or to the right. 
     Thus, the rotation of the handguard  3  is progressively guided up to a maximal lateral opening as represented in  FIGS. 16 and 17 , and it is restricted by the presence of the stops  25  and  23 . 
     As the lateral movement of the conical part  25  is guided by the fixed sliding block  13 , this allows for a gradual and progressive opening movement of the grenade launcher  1 . 
     Since the barrel  4  has now swivelled laterally, the selection of a new grenade to be loaded is not restricted by the opening distance of the grenade launcher  1 . 
     In the case of a grenade  45  whose length is shorter than the opening distance of the grenade launcher  1 , the non-fired grenade can be extracted by means of an automatic extraction device as represented in  FIG. 18 . 
     In case of a longer grenade, the automatic extraction device can be put out of action by pushing the lever  40  of the extractor  38  as the grenade launcher  1  opens. In that case, the non-fired grenade is maintained in the chamber  8  of the barrel  4  thanks to the brake  34 , and the grenade can then be manually extracted into a lateral revolving position of the barrel  4 . 
     It is clear that the grenade  45  can be loaded and extracted on the left side as well as on the right side of the grenade launcher  1 , which has for a result that the grenade launcher according to the invention is useful to a left-hand user as well as a right-hand user. 
     It is clear that the invention is by no means limited to the example described above, but that numerous modifications can be made to the improved grenade launcher while still remaining within the scope of the invention as defined in the following claims.