Barrel and magazine alignment arrangement for a fastening element setting gun

Abstract

An explosive charge driven fastening element setting gun includes a barrel and a rotatable drum-type magazine both axially displaceable within a housing. As the barrel is displaced into the firing position it is arranged to seat into the aligned one of a number of bores in the magazine. A location on each of the axially extending surfaces of the barrel and magazine spaced axially from the location of the other is disposed in clearance-free contact with a surface within the setting gun while the remaining axially extending surfaces of each are spaced radially from the juxtaposed surfaces in the setting gun to provide lateral movement to assure alignment between the barrel and the bores in the magazine when the barrel is moved axially into the firing position.

Description

SUMMARY OF THE INVENTION

The present invention is directed to an explosive charge driven fastening element setting gun in which a barrel and a drum-type magazine are axially displaceable within a housing for movement into the firing condition of the gun and, more specifically, the barrel and magazine are supported within the housing for movement transversely of the axial direction to assure proper alignment when the setting gun is made ready for firing.

In fastening element setting guns which use a drum-type magazine having a plurality of angularly spaced bores for cartridges and fastening elements spaced radially outwardly from and in substantially parallel relationship with the central axis of the magazine, the bore through which the fastening elements are driven consist of two sections, the one within the magazine and another section in the barrel forwardly from the magazine. For reasons of manufacturing tolerances, in known setting guns there has always been a break or gap in the fastening element bore at the junction between the barrel and the magazine or the two bore sections have been axially displaceable relative to one another. Furthermore, the joint between the barrel and the magazine has been rather loose and does not provide an effective seal. As a result, on one hand, the acceleration or penetration behavior of the fastening element is uncontrolled and, on the other hand, due to the loss of the propellent gases at the junction between the barrel and the magazine, a considerable power loss occurs, there is noticeable fouling of the gun and a great amount of noise is developed.

Therefore, it is the primary object of the present invention to provide a bolt setting gun having a rotatable and axially displaceable drum-type magazine where the alignment of the barrel bore and the magazine bores is insured, independent of possible manufacturing tolerances.

In accordance with the present invention, at least one of the axially displaceable barrel and magazine is provided with a radial clearance relative to the juxtaposed surfaces of the setting gun in the range adjacent the ends of the barrel and the magazine which interconnect when the gun is placed in the firing condition.

Due to the lateral displaceability of the barrel and/or the drum, that is, their ability to move transversely of their axial direction when they are interconnected the axes of the barrel bore and the respective bore in the magazine are in alignment. Accordingly, a controlled or defined acceleration or penetration behavior of the fastening element is assured when it is driven into a target material.

Preferably, the barrel and the magazine are each provided with a location at which they are disposed in clearance-free contact with the juxtaposed surface of the setting gun. These locations, one on the barrel and the other on the drum-type magazine, are spaced apart in the axial direction and also from the point at which the barrel and drum contact when the setting gun is placed in the firing condition. The remaining lateral surfaces of the barrel and the magazine are provided with a radial clearance relative to the juxtaposed surfaces of the setting gun. In this manner there is a limited pivotal movement of each of the parts with the locations of clearance-free contact forming fulcrums so that a maximum inclined position of the barrel and magazine, required for the proper alignment of their bore axes, is possible when the setting gun is in the firing condition. It is irrelevant whether the magazine is supported in clearance-free relationship by an axle extending through the center of the magazine or on the surface of the chamber within the gun housing in which the magazine is positioned.

Another feature of the invention is the provision of a projection on the rear wall of the chamber containing the magazine so that the projection faces in the firing direction of the setting gun. When the drum is displaced axially into the firing position, its rear end face contacts the projection on the rear wall of the chamber. The projection assures that the magazine, which has its axis inclined in relation to the central axis of the chamber, is not caused to become aligned by contact with the walls of the chamber which alignment would tend to cancel out the provision for the alignment between the bores in the barrel and the magazine.

Another characteristic of the invention is the provision of complementary frusto-conical or tapered surfaces on the rear end of the barrel and the forward face of the magazine so that the two can seat together and provide an effective seal. The complementary tapered surfaces aid not only in centering the bores in the barrel and the magazine, but also ensure enlarged sealing surfaces and an effecting sealing joint. With this arrangement, the fouling of the gun by explosive gas residues and the noise level emanating from the gun are considerably reduced.

Preferably, the tapered surface is provided in the bore of the barrel diverging outwardly opposite the firing direction with the complementary tapered surface on the magazine being formed as an outwardly directed surface arranged to seat within the tapered surface in the barrel bore. Consequently, the tapered surface within the barrel, which has a large sealing surface to provide an optimum sealing effect, cannot be damaged if the barrel must be removed from the gun, for example, for cleaning. In order to protect the tapered sealing surfaces on the drum magazine they are recessed rearwardly from the front face of the magazine so that it is not possible that they are damaged during magazine rotation or removal.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated and described a preferred embodiment of the invention .

BRIEF DESCRIPTION OF THE DRAWING

In the drawing:

FIG. 1 is a side view, partly in section, of a fastening element setting gun in the rest or non-firing position; and

FIG. 2 is a view similar to FIG. 1 showing the setting gun in the operative or firing position.

DETAILED DESCRIPTION OF THE INVENTION

In the drawing, a fastening element bolt setting gun is shown in the firing position in FIG. 2 and in the non-firing position in FIG. 1. The bolt setting gun includes a housing 1 containing a first bore 2 at its forward or muzzle end containing a barrel 3 which is axially displaceable through the bore between the position shown in FIG. 1 and that indicated in FIG. 2. While there is a radial clearance between the barrel 3 and the surface of the first bore 2 rearwardly of the muzzle end of the gun, the barrel is mounted in clearance-free contact with the inwardly directed shoulder 4 at the muzzle or front end of the first bore 2. As a result, the shoulder 4 forms a fulcrum for the barrel 3 and permits its axis to assume an inclined or angular position relative to the axis of the first bore 2. At the rear end of the barrel, an inner, conically-shaped or tapered surface 5 is provided coaxial with the barrel axis. The tapered surface 5 diverges rearwardly from the diameter of the bore to the rearward force of the barrel. To limit the axial displacement of the barrel within the housing, a circumferentially extending groove or recess 6 is provided in the outer surface of the barrel and it is engaged by a stop screw 7 extending into the groove. Encircling the barrel at its forward end, that is, on the portion of the barrel extending outwardly from the muzzle end of the housing, is a compression spring 8 which biases the barrel forwardly into its non-firing position. Mounted on the forward end of the housing and extending therefrom in the driving direction is a cap 11 held in position by means of a pin 9 for protection against splintering or fragmentation when a fastening element is driven into a target material.

The housing 1 forms a chamber 13 rearwardly of the barrel into which a drum-type magazine 12 is positioned. The magazine 12 has a central bore 14 by which it is mounted on an axle 15 supported in the housing. The magazine 12 is arranged to rotate on the axle 15 at a clearance-free bearing surface 16. As can be seen in the drawing, the bearing surface 16 projects inwardly into contact with the axle 15 while the remainder of the bore 14 is in radially spaced relationship to the axle. Bores 17, 17a are located in the magazine 12 and are disposed in generally parallel relationship to but spaced radially outwardly from the central bore 14 and each of the bores serves to hold a fastening element 18, 18a in its forward end and a cartridge 19, 19a in its rearward end. In FIG. 1, the magazine bore 17 is not disposed exactly parallel to the axis of the barrel, but due to manufacturing inaccuracies it is disposed at a slight angle to the axis of the central bore 14. The front face of the magazine 12, that is, the face directed toward the forward end of the setting gun, has an extension 21, 21a about each of the outlets from the bores 17, 17a which is concentric to the axis of the bore. The lateral surface of each of the extensions 21, 21a forms an outwardly facing frustro-conical or tapered surface 22, 22a which is complementary to the inwardly directed tapered surface 5 in the rearward end of the barrel bore. The radially inner surface 24 of the front face of the magazine is positioned forwardly of the end faces 23, 23a of the extensions 21, 21a so that the extensions do not become engaged in the housing bore 2 which would tend to hinder the rotation of the magazine 12.

To support the magazine 12 in the firing position, as shown in FIG. 2, a projection 25 is provided on the rear face of the magazine chamber 13 in alignment with the barrel 3 in the forward end of the housing 1. As can be seen more clearly in FIG. 1, the projection 25 extends forwardly from the remaining surface of the rear face within the chamber 13.

Within the rear part of the housing, and extending through the projection 25 for contact with the base of the cartridge 19 when the magazine 13 is displaced rearwardly into the firing position, is a firing pin 26. The firing pin is of a known type and is shown only schematically. Centrally positioned in the rear face of the chamber 13 is the combination of spring 27 and a pressure bush 28 which extends into contact with the rear face of the magazine 12. Normally, the spring 27 and bush 28 displace the magazine 12 forwardly for safety reasons so that it is maintained out of the range of action of the firing pin 26 when the setting gun is in the inoperative or non-firing condition.

As mentioned above, FIG. 2 illustrates the operative or firing condition of the setting gun. The forward or muzzle end of the barrel is pressed against a target receiving material 29 and, as a result, is displaced rearwardly into the housing 1 against the biasing action of the compression spring 8 and also of the spring 27. When the barrel is displaced rearwardly, its rearward end enters the chamber 13 and contacts the magazine 12 with the tapered surface 5 within the barrel bore setting against the complementary tapered surface 22 concentrically disposed about the bore 17 in the magazine aligned with the barrel bore. Further, the rearward movement of the barrel presses the drum-type magazine 12 rearwardly until its rearward end surface encircling the rearward end of the bore 17 contacts the projection 25 on the rear face of the chamber 13. It can be noted in FIG. 2, that though the axis of the barrel and the axis of the magazine bore 17 are disposed obliquely to the magazine axis, they have aligned themselves in a straight line. As a result, the axis of the magazine 12 is disposed at a slight angle to the axis of the chamber 13. The ability of the barrel bore and the bore of the magazine to align with one another results from the spaced locations at which the barrel and the magazine are in clearance-free contact with the housing bore 2 and the axle 15, respectively. Since the remaining outer surface of the barrel is spaced radially inwardly from the bore 2 and the remaining surface of the central bore 14 in the magazine 12 is spaced radially outwardly from the axle 15, it is possible to achieve slight angular deviations between the axis of the barrel or the magazine as compared to the axis of the housing bore 2 or the axle 15, respectively. The extent to which the axis of the magazine bore 17 is inclined or angularly displaced relative to the central axis of the magazine determines the degree of angular displacement of the barrel axis with respect to the axis of the housing bore 2. The projection 25 on the rear face of the chamber 13 ensures that the magazine 12 which has its axis disposed angularly to the axis of the chamber 13 is not displaced by contact with the rear face of the chamber so that the alignment of the barrel bore and the magazine bore is not cancelled out.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

Claims

What is claimed is:

1. In an explosive charge driven fastening element setting gun comprising a housing having a front end facing in the firing direction and a rear end facing in the opposite direction, said housing having a first bore extending therethrough rearwardly from the front end, a barrel axially displaceably mounted in said bore in said housing, said barrel having a second bore extending therethrough disposed in generally parallel relation with said first bore and said second bore having a forward muzzle end facing in the firing direction of the setting gun and on oppositely facing rearward end, said housing forming a chamber rearwardly of the first bore and disposed in communication with said first bore, said chamber having a central axis disposed in generally parallel relation with and disposed offset to the axis of the first bore in said housing, a drum-type magazine axially displaceably mounted in said chamber and also mounted for rotation about the central axis of said chamber, said magazine having a plurality of angularly spaced third bores therein disposed in generally parallel relation with the central axis of the chamber and each of said third bores being arranged for general alignment with the first bore in said housing, said magazine having a front face extending transversely of the central axis of said chamber and an oppositely directed rear face, said barrel being displaceable from a non-firing position with the rearward end of the second bore spaced forwardly of said magazine to a firing position with the rearward end of the second bore disposed in contact with the surface of said magazine encircling the front end face of the bore in said magazine which is disposed in general alignment with the first bore in said housing, wherein the improvement comprises that at least one of said barrel at its rearward end within said first bore and said drum-type magazine at its front end within said chamber has a radial clearance relative to said first bore and said chamber, respectively.

2. In a explosive charge driven fastening element setting gun, as set forth in claim 1, wherein each of said barrel and drum-type magazine has a radial clearance relative to said first bore in said chamber, respectively, and said barrel is supported in clearance-free relation with the surface of said first bore in said housing at a position spaced axially forwardly of the rearward end of said first bore, and said magazine is supported in clearance-free relation with said chamber at a position spaced rearwardly from the front face of said magazine.

3. In an explosive charge driven fastening element setting gun, as set forth in claim 2, wherein an axle extends through and generally coaxial with the central axis of said chamber and said axle is supported within said housing, said magazine is rotatably mounted on said axle and is positioned thereon for slidable movement in the axial direction, said magazine having a fourth bore therethrough extending generally coaxially with said chamber and arranged to receive said axle, the surface of said bore at a position spaced rearwardly from the front end face of said magazine having a radially inwardly directed projection disposed in clearance-free contact with said axle.

4. In an explosive charge driven fastening element setting gun, as set forth in claim 3, wherein said chamber has a rear face extending transversely of its central axis and facing in the firing direction of the setting gun toward the rear face of said magazine, a projection formed on the rear face of said chamber extending outwardly therefrom in the firing direction, said projection being aligned with the first bore in said barrel and arranged to contact the rear face of said magazine when it is displaced rearwardly through said chamber.

5. In an explosive charge driven fastening element setting gun, as set forth in claim 1, wherein the rearward end of said barrel and the front face surface of said drum encircling each of said bores having complementary formed conically-shaped surfaces arranged to seat in contact with one another when said barrel is displaced rearwardly into the firing position.

6. In an explosive charge driven fastening element setting gun, as set forth in claim 5, wherein said complementary formed conically-shaped surfaces in said barrel and on said magazine comprise that the surface of said bore at its rearward end has a first tapered surface diverging outwardly from the second bore surface to the rearward end of the barrel and the front face surface of said magazine encircling each of said third bores has an axially extending outwardly facing second tapered surface converging in the firing direction of the setting gun and formed complementary to said first tapered surface.

7. In an explosive charge driven fastening element setting gun, as set forth in claim 6, wherein said chamber having a forward end face extending transversely of and located at the rearward end of said first bore, said front face of said magazine has a portion arranged to contact the forward end face of said chamber and the ends of said second tapered surfaces located closer to the forward end of said barrel are spaced rearwardly from the portion of said front face of said magazine arranged to contact the forward end face of said chamber to permit said drum-type magazine to rotate in said chamber without having the forward ends encircling said second bores becoming engaged within said first bore in said housing.

8. In an explosive charge driven fastening element setting gun, as set forth in claim 3, wherein the end of said first bore at the front end of said housing has an inwardly directed shoulder forming an inwardly facing annular bearing surface with which the outer surface of said barrel is disposed in clearance-free contact and the remaining surface of said first bore rearwardly from said shoulder being disposed in spaced relation to the outer surface of said barrel.

9. In an explosive charge driven fastening element setting gun, as set forth in claim 1, wherein first means are arranged in operative association with said barrel for biasing the barrel in the firing direction and second means are mounted in said housing rearwardly of said chamber for biasing said drum-type magazine in the firing direction.