Mounting device for the detachable attachment of a stock to a system box of a firearm

Abstract

Mounting device (40) for the detachable attachment of a stock (20) to a system box (30) of a firearm (10), with an anchoring element (41) which can be firmly mounted on the shaft (20) or the system box (30), a coupling rod (47) which is movably or firmly anchored to the anchoring element (41) and which is designed to protrude from the anchoring element (41) with its first end section (473) when the anchoring element (41) is mounted, and a clamping element (48) which is movable transversely to the barrel direction of the firearm (10) for locking the coupling rod (47) on the system box (30) or stock (20), characterized in that the coupling rod (47) has an oblique or curved coupling surface (474) at its first end portion (473), and the clamping element (48) when actuated transversely to the direction of travel presses the coupling surface (474) against a counterpart (49) on the system box (30) or shaft (20), wherein the counterpart (49) has a pressure surface shaped opposite to the coupling surface (474), so that radial pressure on the coupling rod (47) by the clamping element (48) causes the coupling surface (474) to move along the pressure surface and thereby pulls the shaft (20) and system box (30) together in the axial direction until their facing sides are pressed flat and precisely against one another.

Description

The present invention relates to a device for detachably fastening a shaft, in particular a back shaft, to the so-called system box of a firearm.Firearms or handguns, in particular repetition bushes or repetition flints for hunting purposes, usually have a barrel, a shaft in the form of a rear and / or front shaft, and a system box fixed therein or therebetween, on or to which the barrel is fastened. All elements essential for firing a shot are accommodated in or on the system box, in particular a breech system, a trigger assembly and, depending on the design of the weapon and if necessary, a magazine.In order to be able to transport such a firearm, which has a certain length due to its design, more comfortably and non-appreciably, but also in order to be able to choose from shafts of different shapes and materials, different solutions have been developed to mount the shaft removably on the system case.The document EP 1 574 806 A1 discloses a rifle with a barrel, a shaft and a system box arranged between the barrel and the shaft. At the front end of the system box in the running direction, a latch is provided which can be moved parallel to the running direction for establishing and releasing the connection between the shaft and the system box.The fastening by means of a shaft screw is very widespread, in particular in hand weapons whose wood or plastic shaft is transversely divided into front and rear shafts, that is to say parallel to the barrel of the firearm. In the publication DE 10 2017 102 005 A1, the shaft screw passes through the rear shaft in the longitudinal direction and can be rotated by an actuating element anchored in the shaft cap.In the publication EP 1 335 174 A1, the front shaft is detachably fixed to the system box together with the barrel. To produce and release the locking, a piston rod passing through the front shaft in the longitudinal or running direction is actuated axially.US 2007 / 0089347 A1 describes a firearm having the features in the preamble of present claim 1. Further conventional firearms are disclosed in US 2010 / 0154274 A1, US 2003 / 0029070 A1, US 1 582 533 A, US 2010 / 0071245 A1 and US 2007 / 0132240 A1.A particular disadvantage of the known solutions is the need for a bore which passes through the shank in the longitudinal direction to receive the shank screw or the piston rod. A search is therefore made for a solid mechanical connection between the shaft and the system box, in which only an end section of the shaft directly adjoining the system box has to be designed for fastening assembly and the remaining part of the shaft is independent thereof.This object is achieved by the mounting device defined in claim 1. The mounting device then has an anchoring element fastened to the shaft or system box and a coupling rod which is movably or fixedly anchored to this anchoring element and can be fixedly coupled to the system box or shaft. Unlike in the conventional fastening solutions with a shaft screw that can be actuated axially, i.e. in the running direction, the coupling rod that extends axially between the system box and the shaft is locked by a clamping element that can be actuated radially, i.e. transversely to the running direction. Thus, the entire mounting device can be accommodated in an immediate boundary area between the system box and the shaft. The remaining shank region remains freely configurable, which--with an unlimited high connection stability--in particular means a saving in material and cost but also entails a simplified construction of the shank.The coupling rod has, on its first end section projecting from the anchoring element, an oblique or curved coupling surface which is pressed by the clamping element against a counterpart attached to the system box or shaft in order to lock the mounting device. The counterpiece has a pressing surface formed opposite to this coupling surface. The coupling surface can be, for example, trough-shaped and the pressure surface the cylinder surface of an essentially cylindrical fastening pin. In any case, the coupling surface should preferably be shaped so as to be at least partially complementary to the pressing surface of the counterpart. In this way, a radial pressure on the coupling rod by the clamping element leads to the coupling surface moving along the pressure surface and thereby contracting the shaft and system box in the axial direction until their facing sides are pressed against one another in a planar and precisely fitting manner. This produces an absolutely firm connection between the shaft and the system box, which can be released again at any time by loosening the clamping element, if necessary. At the end radially opposite the coupling surface, the coupling rod preferably has a straight surface which can subject the clamping element to pressure in a slip-proof manner when the mounting device is tightened.In order to be able to compensate for material changes or manufacturing tolerances, the anchoring element preferably has a screw element arranged in the running direction and a clamping nut rotatably fastened to this screw element. The clamping nut has a through hole for the coupling rod at its end wall, so that a first end portion of the coupling rod protrudes from the anchoring element and a second end portion of the coupling rod is arranged between the end wall of the clamping nut and the screw element. This is advantageous in particular when the shaft is made of wood and therefore is exposed to more severe material changes than, for example, a plastic shaft.In order to be able to mount the shank without radial displacement, the end wall of the clamping nut preferably has a conically or spherically portion-shaped tapered inner surface which is formed complementary to a conically or spherically portion-shaped tapered outer diameter at the second end portion of the coupling rod. As a result, the coupling rod is axially anchored within the anchoring element, but remains freely rotatable within a cone corresponding to the cone angle of the conical surfaces or the curvature of the ball section. The outer surface of the cone is swept over when the two oppositely shaped contact surfaces of the end wall and of the second end section are moved slidingly relative to one another. This free movability is particularly favorable for coupling the coupling rod to the counterpart with the clamping element still open. This free movability can, however, also be omitted and the coupling rod can also be radially fixedly anchored in the anchoring element.In particular, when during assembly a radial displaceability is provided in a different manner between the shaft and the system box.The freedom of movement of the coupling rod is preferably further limited in that a first anti-rotation means is provided between the screw element of the anchoring element and the coupling rod, which ensures that the coupling rod can only be pivoted about an axis transverse to the running direction. The anti-rotation means is preferably achieved in that a radial slot is provided on an end wall of the screw element, in which slot a disk-shaped projection formed on the second end section of the coupling rod engages. This ensures that the coupling rod is always oriented in a specific rotational position with respect to the screw element, namely in the rotational position in which the coupling surface at the first end section faces the counterpart.A second anti-rotation device can furthermore ensure that the screw element always remains positioned in the rotational position matching the disk-shaped projection. This is preferably achieved in that a rubber ring is provided between the screw element and the bushing fastened in the shaft or system box.The solution according to the invention is particularly practicable and simple if the clamping element is a grub screw that can be actuated in the radial direction. This can be actuated by a corresponding wrench, which can preferably be accommodated in the firearm, so that the mounting device can be locked and released by the user himself and on site. In this way, in particular, the rear stock, but preferably also the front stock, can be exchanged for a short time by means of a single tool. However, other clamping elements are also possible, in particular a clamping element designed as a bayonet lock.Generally, in the present specification, the direction of travel of the firearm is referred to as the axial direction and the transverse directions are referred to as the radial directions. In addition, the radial directional indications "up", "down", "left" and "right" are understood with reference to a gun which looks in the running direction and holds the firearm in its normal position of use.The invention will be explained in more detail below on the basis of exemplary embodiments with reference to the drawings. The following shows: FIG. 1 shows a cross section through a firearm according to the invention with the mounting device in the open position, FIG. 2 is a cross-section according to FIG. 1 with the mounting device in the closed position, FIG. 3 is a perspective view of the mounting device in the open position, FIG. 4 is a perspective view of the mounting device in the closed position; and FIG. 5 is perspective views of the end walls of the coupling rod and the screw element facing each other in use.FIGS. 1 and 2 each show a firearm 10 in longitudinal section along the barrel of the firearm 10, not shown in detail. a so-called system box 30 contains all the technical components necessary for firing the shot and is connected to the rear shaft 20 in the partial area shown here by the mounting device 40 according to the invention. At the opposite front end of the system box 30, there is further attached a front shaft (not shown) which may be fixed by a mounting device of the same design.The system box 30 and the rear shaft 20 have at their connecting region 25 surfaces which are shaped in each case in a complementary manner to one another and which are pressed against one another in a planar and / or positive-locking manner when the mounting device 40 is closed. The particular factor in the mounting device 40 according to the invention is that it is possible to clamp the rear shaft 20 in the axial direction against the system box 30, without the associated clamping element 48 having to be moved in the axial direction. Rather, the clamping element 48 is actuated from above only in the radial direction, so that neither the rear shaft 20 nor the system box 30 has to be provided with a connecting element passing through it in the longitudinal direction.The central element for this is the coupling rod 47, which protrudes with its first end section 473 axially from the rear shaft 20 and in the exemplary embodiment shown here is anchored with its second end section 471 in the rear shaft 20 in a radially movable manner by the anchoring device 41. In the exemplary embodiment, the anchoring element 41 is arranged in the rear shaft 20 and couples to a corresponding counterpart 49 on the system box 30. However, the counter piece 49 could also be arranged in the rear shaft 20 and the anchoring element 41 could be arranged accordingly in the system box 30.The rear shaft 20 has, at its boundary surface facing the system box 30, an axial bore 21, into which a bushing 42 is firmly screwed and preferably also glued. The bushing 42 has an internal thread into which the screw element 43 is screwed firmly with a first threaded part 43A until the stop. The second threaded part 43B protrudes from the bushing 42. The threaded parts 43A, 43B have different diameters and a rubber ring 44 (only shown schematically in FIG. 4 ) can be arranged on the first threaded part 43A in the transition region. The rubber ring 44 then comes to lie between the second threaded part 43B and the bushing 42 and, because of its flexibility and friction, leads to the position of rotation of the screw element 43 being able to remain fixed in a specific position. Unlike in the exemplary embodiment shown, the bushing 42 can also be omitted and the axial bore 21 itself can have an internal thread corresponding to the bushing 42.In the axial bore 21 of the rear shank 20, a clamping nut 46 is also accommodated, which is screwed onto the second threaded part 43B of the screw element 43. In the exemplary embodiment shown, the clamping nut 46 lies completely within the axial bore 21 of the rear shank 20 and a certain free space 22 exists between its rear end 468 (see FIGS. 3 and 4 ) and the bushing 42; as a result, the clamping nut 46 remains axially adjustable, so that, for example, readjustment of the anchoring element 41 is possible at any time, for example in the event of a wood shrinkage of the rear shank 20.The clamping nut 46 has, on its side facing the system box 30, an end wall 460 with a through hole 461 for the coupling rod 47. the coupling rod 47 protrudes with its first end section 473 through the through hole 461, but is retained at its second end section 471 by the clamping nut 46. The inner surface 462 of the end wall 460 is formed to taper forward in the radial direction. The taper can in particular be conical or have the shape of a spherical segment surface. The second end section 471 of the coupling rod 47 has a surface 472 with an outer diameter which narrows towards the front in a complementary manner to this narrowing. As a result, the coupling rod 47 remains axially anchored within the anchoring element 41, but can be moved freely radially, namely within a conical region which is predefined by the cone angles of the mutually corresponding conical surfaces on the inner surface 462 of the end wall 460 and the outer surface 472 of the end section 471 or the associated angles of the spherical section surfaces.As can best be seen in FIG. 5, this free radial movability is now additionally restricted in that a projection 476 is formed on the second end section 471 of the coupling rod 47 at its end wall 470. The projection 476 is disk-shaped in the exemplary embodiment shown. It engages in a correspondingly shaped slot 436 on the end wall 460 of the screw element 43. The engagement of protrusion 472 and slot 436 reduces the movability of the coupling rod 47 to an upward and downward movement as illustrated by the and different positions of the coupling rod 47 in FIGS. 1 and 2. A helical spring 45 inserted into a blind hole 431 in the middle of the slot 436 (see FIG. 1 ) still ensures in the exemplary embodiment shown that the coupling rod 47 is prestressed against the screw element 43. Thus, the two mutually complementary surfaces 462, 472 on the clamping nut 46 and the coupling rod 47 are pressed against one another by the spring force and remain constantly in sliding contact, which significantly facilitates the assembly. The spring 45 can, however, also be replaced by a different type of prestressing element or can be omitted altogether.In FIG. 1, the coupling rod 47 is deflected upward to the maximum, and the clamping element in the form of the grub screw 48 is in its uppermost screw position. Thus, the coupling rod 47 can be pushed into the system box 30 to such an extent that a nose-shaped part 477 of the first end section 473 comes to lie behind the cylindrical transverse pin 49. When the grub screw 48 is now screwed down in the threaded bore 31 into the position shown in FIG. 2, it presses from above against the surface 475 of the coupling rod 47 and allows the coupling surface 474 to slide along the lateral surface of the transverse pin 49. Due to the curvature of these surfaces, the shaft 20 is thereby drawn onto the system box 30 until its boundary surfaces 25 are pressed firmly and flatly against each other. This results in an absolutely fixed anchoring of the shaft 20 on the system box 30, which can be released again at any time by screwing on the grub screw 48, if necessary.Instead of the trough shape in the exemplary embodiment shown, the coupling surface 474 can also be formed, for example, only as a straight inclined surface or as a singly curved surface. It is only important that the coupling surface 474 changes in its radial dimension toward the counterpart 49 and thus enables a planar contact against an oppositely shaped contact surface of the counterpart 49.In summary, the present invention relates to a mounting device 40 having an anchoring element 41 fixedly mounted on the shank 20 of a firearm 10, from which an anchoring rod 47 movably or fixedly anchored therein protrudes. The coupling rod 47 engages with its first end section 473 behind a counter piece fastened to the system box 30. The shaft 20 can be clamped firmly in the axial direction in a planar manner against the system box 30 by the clamping element 48 being actuated from above in the radial direction without a connecting element passing through the shaft 20 in the longitudinal direction having to be provided on the shaft.List of reference characters10 Firearm 20 rear shaft 21 axial bore 22 free space 25 connecting region 30 system box 31 threaded bore 40 mounting device 41 anchoring element 42 bushing 43 screw element 43A first threaded part 43B second threaded part 430 end wall 431 blind hole 436 slot 44 rubber ring (second anti-rotation means) 45 spring 46 clamping nut 460 end wall 461 through hole 462 conical inner surface 468 rear end 47 coupling rod 470 end wall 471 second end section 472 conical outer wall 473 first end section 474 coupling surface 475 straight surface 476 projection (first anti-rotation means) 477 nose-shaped part 48 grub screw (clamping element) 49 transverse pin (counter piece)

Claims

Mounting device (40) for the detachable fastening of a shaft (20) to a system case (30) of a firearm (10), having an anchoring element (41) which can be fixedly mounted on the shaft (20) or the system case (30), a coupling rod (47) which is movably or fixedly anchored on the anchoring element (41) and is designed to project with its first end section (473) from the anchoring element (41) when the anchoring element (41) is mounted, and a clamping element (48) which can be moved transversely to the running direction of the firearm (10) in order to lock the coupling rod (47) on the system case (30) or shaft (20), characterized in that the coupling rod (47) has an oblique or curved coupling surface (474) at its first end section (473), and the clamping element (48) presses the coupling surface (474) against a counter piece (49) on the system box (30) or shaft (20) when it is actuated transversely to the running direction, wherein the counter piece (49) has a pressing surface which is shaped opposite to the coupling surface (474), such that a radial pressure on the coupling rod (47) by the clamping element (48) leads to the coupling surface (474) moving along the pressing surface and as a result the shaft (20) and system box (30) contracting in the axial direction until their facing sides are pressed against one another in a planar and precisely fitting manner.The mounting device (40) of claim 1, wherein the coupling surface (474) is trough-shaped, the mating part is a substantially cylindrical fastening pin (49), and the coupling surface (474) is shaped to conform to the cylindrical surface of the fastening pin (49).Mounting device (40) according to claim 1 or 2, wherein the coupling rod (47) has, at its first end portion (473), on the side opposite the coupling surface (474) transversely to the running direction, a surface (475) for pressing on the clamping element (48).The mounting device (40) according to any one of the preceding claims, wherein the anchoring element (41) comprises a screw element (43) arranged on the shaft (20) or the system box (30) in the running direction and a clamping nut (46) rotatably fastened to the screw element (43), and the clamping nut (46) comprises a through hole (461) for the coupling rod (47) on its end wall (460), such that a second end portion (471) of the coupling rod (47) is arranged between the end wall (460) of the clamping nut (46) and the screw element (43).Mounting device (40) according to claim 4, wherein the end wall (460) of the clamping nut (46) has a tapered inner surface (462) on its inner side, and the coupling rod (47) has an outer wall (472) with a diameter tapering in the opposite direction to this inner surface (462) on its second end section (471).Mounting device (40) according to claim 4 or 5, wherein the second end section (471) of the coupling rod (47) has a first anti-rotation means with respect to the screw element (43) on its end wall (470).Mounting device (40) according to claim 6, wherein the first anti-rotation means is an axial projection (476) which engages in a slot (436) on an end wall (430) of the screw element (43) and enables the coupling rod (47) to be pivoted about a pivot axis running transversely to the running direction, but does not allow the coupling rod (47) to rotate with respect to the screw element (43).Mounting device (40) according to one of Claims 4 to 7, wherein a second anti-rotation means (44) is provided between the screw element (43) and a bushing (42) fastened in the shank (20) or system box (30), said second anti-rotation means ensuring that the slot (436), when the screw element (43) is tightened in the bushing (42), can always be in a specific rotational position which is aligned with the projection (476) of the coupling rod (47).Mounting device (40) according to one of the preceding claims, wherein the clamping element (48) is a screw which can be actuated in a threaded bore (31) running transversely to the running direction in the system box (30).Firearm (10) having a system box (30), a shaft (20) and the mounting device (40) according to one of the preceding claims for the detachable fastening of the shaft (20) to the system box (30).

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