WO1992007230A1

WO1992007230A1 - Sight mounting bracket

Info

Publication number: WO1992007230A1
Application number: PCT/AU1991/000472
Authority: WO
Inventors: Albert Smith
Original assignee: Commonwealth Of Australia
Priority date: 1990-10-15
Filing date: 1991-10-15
Publication date: 1992-04-30

Abstract

A telescopic sight attachment bracket (3) comprising an elongate flanged member (4) adapted to be attached to a sight mounting bracket (3) of a rifle, and at least two support mounts (14, 15) adapted to support a telescopic sight (1), each of said mounts (14, 15) having brackets which are slidably and fixably engageable with dove-tailed flanges on said flanged member (4). Each dove-tailed flange has a pair of spaced cut-outs and the flanged member (4) includes a ramp positioned proximate said cut-out portion such that when said sight is being detached from the rifle by sliding movement of said brackets along the dove-tailed flanges, the ramp causes one of said mounts (14, 15) which is drawn over the ramp to disengage from said dove-tailed flanges by lifting the brackets upwardly and clear of said cut-out portion, one of said mounts (14, 15) has a catch (22) which is releaseably engageable with a projection on said flanged member (4) for preventing sliding displacement of said sight (1) relative to the flanged member (4).

Description

TITLE

SIGHT MOUNTING BRACKET

FIELD OF THE INVENTION

This invention relates to means for attaching telescopic sights to small arms. Whilst throughout this specification reference is made to a rifle it is understood that the expression embraces a variety of small arms such as rifles -sub machine guns and other similar weaponry.

A telescopic sight allows a marksman to aim a rifle with a high degree of accuracy. Clip-on telescopic sights are known which may be attached to a rifle only as required. Means for attaching clip-on sights must be designed to ensure precision and consistency of alignment each time the sight is attached to the rifle. However, rifles which are intended primarily for military use are required to be able to withstand extremely harsh tests such as being dropped from chest height onto a concrete floor. Any sighting system which is attached to the rifle is also expected to withstand this harsh treatment and to remain in perfect alignment.

DISCUSSION OF PRIOR ART

The optics of the telescopic sight of a standard Steyr rifle (F88S) are housed in a sturdy casing that is formed as part of a mounting bracket which is an integral component of the housing of the rifle. If the rifle is to be used with an infra-red night sight, the telescopic day sight has to be removed thus entailing removal of the integral component of the housing of the rifle. Thus the carrying of both sights renders the assembly rather bulky and cumbersome.

SUMMARY OF THE INVENTION

According to the present invention there is provided a telescopic sight attachment bracket comprising an elongate flanged member adapted to be attached to a sight mounting bracket of a rifle, and at least two support mounts adapted to support a telescopic sight, each of said mounts having brackets which are slidably and fixably engagable with dove-tailed flanges on said flanged member.

It is preferred that each of said dove-tailed flanges has at least one cut-out portion whereby, at least one of said mounts is disengagable with said dove-tailed flange member at said cut-out portion. Preferably, said flanged member includes a ramp positioned on a top surface of said member and proximate said cut-out portion such that when said sight is being detached from the rifle by sliding movement of said brackets along the dove-tailed flanges, the ramp causes one of said mounts which is drawn over the ramp to disengage from said dove-tailed flanges by lifting the brackets upwardly and clear of said cut¬ out portion. One of said mounts advantageously has a catch which is releasably engagable with a projection on said flanged member for preventing displacement of said sight upon recoil of the rifle.

Preferably, the catch includes a beak portion having an inclined forward end and slot positioned rearwardly of the forward end, the beak portion being biased downwardly so that the forward end rides over the projection on the flanged member until the projection locates within the slot.

DESCRIPTION OF THE DRAWINGS

In order that the invention may be more fully understood, two embodiments of the invention will be described by way of example only with reference to the accompanying drawings in which:

Fig. 1 illustrates a Steyr rifle with a telescopic sight attachment bracket constituting one embodiment of the invention,

Fig. 2 is a side elevational view of the attachment bracket shown in Fig. 1,

Fig. 2A is a cross-sectional view of the attachment bracket taken along line A-A of Fig. 2,

Fig. 3 is a side elevational view of a telescopic day-sight of Fig. 1 illustrating rear and forward support mounts, Fig. 4 is an enlarged view of the telescopic day-sight and support mounts attached to a mounting bracket of the Steyr rifle,

Fig. 5A is a front-on view and Fig. 5B is a side-on view of the forward support mount of Fig. 3,

Fig. 6 is a side-on view of a Steyr rifle with an attachment bracket of a second embodiment of the present invention used to attach a night-sight to the rifle,

Fig. 7 is a side elevation view of the attachment bracket of Fig. 6, and,

Fig. 7A is a front-on view of the attachment bracket of Fig. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiments of this invention relate to a special version of the Steyr rifle (F88S) that has a mounting bracket that is an integral part of the breech of the rifle. This invention concerns a special attachment bracket that enables fitting of different sight systems. Whilst the attachment bracket is designed for a Steyr rifle, it is understood that the invention has application to other makes and models of small-arms. The invention embraces a detachable telescopic sight based on the design of the inbuilt sight of the standard Steyr sight. This sight has been developed so that it can be removed from the weapon quickly and easily whilst maintaining the robustness of the integral sighting system. It is of paramount importance that alignment of the sights is maintained throughout all fitting and removal of detachable sights. The mounting system of the invention achieves this requirement.

The attachment bracket of the present invention also enables the fitting of other sighting systems. Referring to the drawings, Figs. 1 and 6 illustrate embodiments of the invention which have been adapted to enable he attachment, respectively, of a day-sight 1 and a night-sight 2 to the mounting bracket 3 of the F88S Steyr rifle.

The mounting bracket 3 of the Steyr rifle is illustrated in Figs. 2 and 2A. An elongate flanged member 4 is fastened to the mounting bracket by screws 5 and washers 6. Each longitudinal side of the flanged member 4 is provided with a dove-tailed flange 7 positioned along a substantial portion of the length of the flanged member, except for two cut-out portions 8, 9 where the sides 10 of the flanged member 4 are vertical, as can be seen in, the sectional view of Fig. 2A. A small ramp 11 is positioned on the top surface of the flanged member 4 proximate the forward-most cut-out portion 8. The ramp 11 has a sloping surface 12 which slopes forwardly. (The forward part of a rifle is defined as that part which is closest to the gun muzzle) . A small upright projection 13 is positioned to extend transversely of the forward-most end of the flanged member 4.

The telescopic day-sight, as shown in Fig. 3, is supported on a rear support mount 14 and a forward support mount 15. Each mount, as illustrated in Figure 5A, has a pair of brackets 16 which are able to slidably engage with the dove¬ tailed flanges 7 of the flanged member 4. Telescopic sights must be mounted in precise alignment with respect to the axis of the rifle barrel. Since the forward and rear support mounts 14 and 15 are both mounted on the same flanged member 4, misalignment of the front and rear support mounts, with respect to one another, is minimised. Hence, correct alignment of the support member 4 on the rifle will ensure correct alignment of both the front and rear support members. Each of the support mounts 14, 15 has a collar assembly which is adapted to surround the barrel of the telescopic day-sight. The collar assembly is divided into two separable halves 17, 18 so that the two halves may be brought together to surround and clasp the bore of the telescopic day- sight. The two halves of the collar assembly are tightened together by four cap screws 19. The lower half 18 of the collar assembly incorporates the two brackets 16. The base of each bracket is provided with an inwardly projecting claw 20 having an inwardly sloping surface 21 which combines to form a mortise whose cavity shape complements the dove-tailed shape of the flanges on the elongated flanged member 4. Thus, the claws 20 of the brackets of each support member are able to slidably engage with the flanges 7 on the flanged member 4 with a highly toleranced fit. Moreover, the dove-tail engagement of the support mounts with the flanged member ensures that the telescopic day-sight can only move axially along the length of the flanged member. The dove-tailed fit of the claws with the flanges also ensures consistent alignment of the telescopic sight each time the sight is attached to the rifle.

In order to axially secure the telescopic sight in place, that is to prevent displacement of the telescopic sight either rearwardly or forwardly upon recoil of the rifle, the forward support mount 15 is provided with a catch 22 which is releasably engagable with the small upright projection 13 on the end of the flanged member. As shown in Figure 5B the catch includes a beak portion having an inclined forward end 22A. The rearward end of the beak portion terminates in a lateral groove 23 which is adapted to fit over the small projection 13. The catch pivots about a shaft 29 that extends transversely of brackets 20. A segment 24 of the shaft 29 of the catch is cutaway to a clevis to accommodate a coil spring 25. One end of the coil spring 26 acts upon the catch and resiliently urges the catch downwardly. When the telescopic sight is being attached to the rifle, the inclined forward end 22A makes initial contact with the small projection 13 on the flanged member. The catch rides over the projection like a cam until the groove 23 in the catch engages the small projection 13. The groove 23 of the spring loaded catch is urged downwardly onto the projection 13, thus ensuring that the telescopic sight is fixed in position and cannot be displaced either rearwardly or forwardly until the catch is lifted off from the small projection 13. Once the telescopic sight has been positioned on the mounting bracket 3, the brackets 16 of each support mount 14, 15 may be drawn together by tightening a winged bolt 27 which passes through one bracket, to engage a nut 28 positioned in the opposite bracket. As shown in Figure 2, each of the dove-tailed flanges positioned on the sides of the elongate flanged member 4 is provided with a forward cut-out portion 8 and a rear cut-out portion 9. If not for these cut-out portions, the telescopic sight would have to be attached to and detached from the rifle by guiding both of the support mounts along the entire length of the flanged member 4. The cut-out portions 8, 9 each provide a break in the dove-tailed flanges 7 which allow the support mounts to be assembled to or to be lifted off the flanged member. Hence, in order to attach or detach the telescopic sight, the support mounts need only be guided part of the way along the flanged member. The cut-out portions 8 and 9 on each flange are spaced apart by a distance which generally corresponds to the distance separating the two support mounts 14, 15 attached to the telescopic sight. This correspondence of the spacing of the cut-out portions with respect to the spacing of the support mounts enables the two support mounts to be engaged with and disengaged from the flanged member simultaneously. When detaching the telescopic sight, it is important that the clawed brackets of the support mounts are lifted away from the flanged member once the entire bracket has been moved into the cut-out portion. Otherwise, there is the possibility that the claws of the forward support mount 15 may re-engage with the flanges if the bracket of the forward support mount 15 is guided past the forward cut-out portion 8. Of greater concern is that the claws 20, which are still firmly engaged with the horizontal sides of the cut-out portion, may only partially disengage with the flanged member 4 and that the claws may be jammed onto the leading edge 39 of the flanged portion as the support mounts continue to be guided rearwardly. In order to ensure that the claws disengage the flanged member at precisely the right moment, the small ramp 11 is so placed that when the detachable sight is moved rearwards, the rear of the catch contacts the slope 12 of the ramp, thereby forcing the forward support mount upwards and disengaging the brackets from the flanged member and out of the forward cut-out portion 8. The further example, illustrated in Figs. 6 and 7, shows how the present invention may be embodied to attach the telescopic night-sight 2 to the Steyr rifle. The night-sight 2 is supported on a mounting base 30 which is positioned proximate the middle of the night-sight. In turn, the mounting base 30 is positioned on an elongated support beam 31. A forward support mount 15 and a rear support mount 14 are formed as integral parts of the support beam 31 and are substantially similar to the support mounts of the first embodiment. The support mounts 14, 15 are able to engage with the flanged member 4 in the same manner as the previously described embodiment. The majority of optical elements in any telescopic sight are positioned towards the forward portion of the telescopic sight. Hence, the centre of gravity of the telescopic night-sight 2 is not located in the middle of the night-sight, but is to be found more towards the forward part of the night-sight. Therefore, the forward and rear support mounts 14, 15 are positioned on the support beam 31 such that the centre of gravity of the night-sight is located in between the support mounts. Even with a telescopic sight of substantial bulk such as the night-sight 2, the mounting means of the present embodiment is able to ensure precision and consistency of alignment each time the sight is attached to the rifle. More importantly, the mounting means of the embodiments of the invention are able to withstand extremely harsh treatment, such as being dropped from chest height onto a concrete floor without damage to the alignment of the telescopic sight. The optical system of the telescopic day- sight 1 is housed in an extremely strong shock resistant casing and, when fitted to the rifle, will withstand the same harsh treatment as the rifle.

The embodiments have been advanced by way of example only and modifications are possible within the spirit and scope of the invention.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A telescopic sight attachmentbracket comprising an elongate flanged member adapted to be attached to a sight mounting bracket of a rifle, and at least two support mounts adapted to support a telescopic sight, each of said mounts having brackets which are slidably and fixably engagable with dove-tailed flanges on said flanged member.

2. The attachment bracket according to claim 1 wherein each of said dove-tailed flanges has at least one cut¬ out portion whereby, at least one of said mounts is disengagable with said dove-tailed flange member at said cut¬ out portion.

3. The attachment bracket according to claim 2 wherein said flanged member includes a ramp positioned on a top surface of said member and proximate said cut-out portion such that when said sight is being detached from the rifle by sliding movement of said brackets along the dove-tailed flanges, the ramp causes one of said mounts which is drawn over the ramp to disengage from said dove-tailed flanges by lifting the brackets upwardly and clear of said cut-out portion.

4. The attachment bracket according to claim 3 wherein the mounts are spaced apart along the length of the sight the flanged member having cut-out portions in each dove-tailed flange spaced to proximate the spacing of the mounts.

5. The attachment bracket according to any one of the preceding claims wherein one of said mounts has a catch which is releasably engagable with a projection on said flanged member for preventing sliding displacement of said sight relative to the flanged member.

6. The attachment bracket according to claim 5 wherein the catch includes a beak portion having an inclined forward end and slot positioned rearwardly of the forward end, the beak portion being biased downwardly so that the forward end rides over the projection on the flanged member until the projection locates within the slot.

7. The attachment bracket according to any one of the preceding claims wherein each mount includes adjustable means to clamp the brackets into engagement with the dove-tailed flanges.

8. A rifle comprising a stock and a barrel with a breech positioned therebetween, a sight mounting bracket formed integrally with the breech and arranged to detachably support a telescopic sight attachment bracket according to any of claims 1 to 7.