Patent Description:
Reflector sights for firearms are well known. Reflector sights tend to be either open, wherein the light beam travels through a region which is open to the environment, or closed, wherein the light beam is entirely enclosed. The front of the sight is taken to be the side facing towards the target when the sight is mounted on a firearm during use. The rear of the sight is taken to be the side facing towards the user when the sight is mounted on a firearm during use. A closed sight typically comprises a housing incorporating front and rear windows (i.e. transparent screens), and a lens inside the housing onto which the reticle is projected.

Closed sights tend to provide a robust and weather-proof design, useful for harsh conditions wherein rain, snow, dust or other foreign matter would otherwise be problematic. Closed sights therefore offer a high level of reliability and tend to be favoured for use in combat applications. A drawback with closed sights is increased weight and bulk, and a requirement for a specific mount due to the larger size. The Applicant's own switchable interface sight (SIS) is an example of such a closed sight.

There is a desire now to further improve on existing closed sight designs, particularly to provide a more compact closed sight with a considerably reduced size, so that the sight can be used interchangeably with an open sight on the same mount.

<CIT> discusses a dot sight device, which includes a window frame enclosing a transparent lens; a body plate extending from the window frame; a light emitter disposed on the body plate, and configured to emit a light that forms a pattern on the transparent lens.

The present invention seeks to mitigate the above-mentioned problems. Alternatively or additionally, the present invention seeks to provide an improved reflector sight.

In a first aspect, the present invention provides a reflector sight for a firearm, the sight comprising: a base; a housing arranged on the base, together defining an inner chamber, the housing comprising a roof, two or more sides, a front window and a rear window; and a light source; wherein the base comprises a bridge defining a tunnel therethrough; the sight is a closed sight, wherein the inner chamber is sealed by a combination of the base, the roof of the housing, the sides of the housing and the front and rear windows of the housing, together with the bridge; and wherein the light source is arranged with respect to the base to emit light through the tunnel and into the chamber.

A closed sight is known in the art to mean a sight wherein the light path is enclosed (i.e. not exposed to the external environment).

The inventors have recognised that by incorporating a bridge on the base of the sight, a more compact closed sight is provided. The tunnel provides a pathway for light to pass into the chamber without obstruction by the base, whilst simultaneously creating space within the base for the re-positioning of the mounting holes used to fix the sight onto the mount (i.e. mounting plate or slide). Thus, the mounting holes can be positioned forward of the light source (i.e. closer to the target), rather than rearward, as has been the state of the art for closed sights. As such, the footprint of the sight is reduced, and can be made to match standard footprints already used in the industry for smaller, open sights. This provides a significant benefit to the user, who can interchange the reflector sight of the present invention with existing open sights, without needing any reconfiguration of the firearm mount.

Building a bridge onto the base of a sight is counterintuitive, since it partially obstructs the field of view. However, the inventors have discovered that during use which tends to be with two eyes open, the bridge itself becomes essentially invisible to the user, whilst the reflected reticle is superposed over the top.

The housing may be six sided. The chamber may be substantially cuboidal. The weight of the sight may be no more than <NUM>, for example in the range <NUM>-<NUM>. The base may comprise a first portion which is covered. The base may comprise a second portion which is exposed (i.e. open to the external environment).

The base may comprise a top surface. The bridge may be raised up from (i.e. upstanding on) the top surface. The bridge may be external to the chamber. The bridge may adjoin an external surface of the housing.

The light source may comprise one or more LEDs. The sight may be a red dot sight. The light source may be attached to the base, held by the base, or otherwise associated with the base.

The bridge may be adjacent the housing. The bridge may be adjoined to the housing. The bridge may comprise one or more walls, wherein the walls have a maximum thickness of less than <NUM>.

The tunnel may be defined in part by the base and in part by the bridge. The tunnel may extend beneath the top surface of the base. The tunnel may be partially within the base and partially above the base. The light source may be positioned beneath a top surface of the base. The tunnel may extend beneath a top surface of the base to a lower tunnel end, and the light source may be mounted at the lower tunnel end.

The tunnel may be positioned between the light source and the chamber. The light source may be mounted on one end of the tunnel, to emit light directly into the tunnel. The tunnel may be straight, such that the emitted light follows a direct and unobstructed path to the chamber.

The sight may comprise a lens within the chamber, wherein the light source is positioned at the focal point of the lens. The housing comprises a front window (wherein front is taken to be the side facing the target during use). The front window may comprise a transparent panel. The housing comprises a rear window (wherein rear is taken to be the side facing the user during use). The rear window may comprise a transparent panel. The rear window may be adjacent the bridge, for example the bridge may adjoin the rear window. When viewed from the rear, the bridge may cover a surface area which is less than <NUM>%, for example <NUM>%, of the external surface area of the rear window. The housing comprises a roof. The housing comprises two or more sides.

The bridge may be taken to have a front end and a rear end (along a longitudinal axis of the bridge), wherein the front end is the end nearer the target during use, and the rear end is the end nearer the user during use. The bridge may comprise a cover, for example over one end. In other words, the bridge may be capped at one end. The covered end may be the rear end. The cover may be transparent. The use of a transparent cover may improve viewing of the reticle (since it can be viewed through both the rear window and transparent cover), whilst minimising the obstructive effect of the bridge within the field of view.

The rear end of the bridge may be angled with respect to an upper surface of the base. The cover may be angled with respect to an upper surface of the base. The cover may be tilted towards the front of the sight (i.e. sloping away from the user during use).

The chamber is sealed (i.e. the sight may be waterproof). The chamber is sealed by a combination of the base, the roof of the housing, the sides of the housing and the front and rear windows of the housing, together with the bridge (including cover). A sealed sight may be particularly desirable for use in harsh environments.

The bridge may be elongate, i.e. having a maximum length which is greater than its maximum width and its maximum height. The bridge may have an approximately square, or approximately rectangular, cross-section. The cross-sectional area of the bridge may increase with distance towards the front of the sight (i.e. closer to the target). The increase in size may be continuous with distance towards the front of the sight.

The bridge may have a maximum height which is less than one half, for example less than one third of a maximum height of the rear window. The bridge may have a maximum width which is less than one half of a maximum width of the rear window. The bridge may have an average width which is less than one half, for example less than one third of a maximum width of the rear window (wherein the average width is taken to be the width of the bridge at half its maximum height, and half its maximum length). The bridge may obstruct approximately <NUM>-<NUM>% for example <NUM>-<NUM>% of the surface area of the rear window of the sight. The bridge may comprise walls, for example comprising a roof and two side walls. The walls may be elongate walls. The walls may have a variable thickness along the length of the bridge. The maximum thickness may be less than <NUM>, for example less than <NUM>. The walls may have a thickness between <NUM>-<NUM> thick along their full length, for example between <NUM>-<NUM> thick. The walls of the bridge may thus be sufficiently thick to provide strength, but be thin enough to minimise obstruction of the rear window of the sight.

The bridge may have rounded edges. The rounded edges may extend along the full length of the bridge.

The bridge may be aligned centrally on the base. The bridge may be aligned along a central longitudinal axis of the sight.

The housing may comprise a front window and a rear window, the front window being closer to the target during use, and the rear window being closer to the user during use, wherein the bridge adjoins the rear window. The bridge may obstruct a portion of the rear window when viewed from the rear.

The sight may comprise a lens in the chamber. The lens may be a convex lens. The lens may bisect the chamber. The light source may be positioned at the focal point of the lens.

The light source may be mounted at one end of the tunnel.

The bridge may be formed integrally with the base. The housing may be formed integrally with the base.

The base may comprise holes for receiving mounting screws. The holes may be threaded. The holes may extend through the full depth of the base. The holes may be positioned forward of the light source (i.e. closer to the housing than the light source). The holes may be positioned between the light source and the housing. There may be one or more holes, optionally two holes for receiving mounting screws. The holes may be located on the base in a position such that the base fits onto a mount designed for an open sight. The mount may be a mounting plate or a firearm slide which has been machined to receive a certain footprint of sight. The sight of the present invention may therefore be said to have a standard (i.e. known in the art) footprint.

The base may have a maximum width of less than <NUM>, optionally less than <NUM>. The base may have a maximum width in the range of <NUM>-<NUM>. The base may have a maximum length of less than <NUM>, optionally less than <NUM>. The base may have a maximum length in the range of <NUM>-<NUM>.

The base may comprise, in addition to the holes for receiving mounting screws, one or more, optionally four, locating recesses for receiving locating pegs of a complementary sized mount.

In a second aspect of the invention, there is provided a reflector sight assembly comprising the reflector sight of the first aspect, and a mount configured to hold the sight. The mount may be a mounting plate configured to attach to the firearm. The mount may be a portion of a slide of the firearm. The mount may have dimensions which are slightly larger than the sight so that the sight can fit inside the perimeter of the mount. The perimeter of the mount may comprise a raised lip. The mount may comprise four upstanding locating pegs, each having a height of approximately <NUM>. During use, when the sight is mounted on the mount, the locating pegs of the mount may be inserted in the locating recesses of the base of the sight.

The mount may have a footprint which matches the Applicant's Glock MOS low profile mounting plate designed for the Reflex Mini Sight, Shield Mini Sight and Jpoint Sight products. The sight of the reflector sight assembly may therefore be interchangeable on the same mount, with the Reflex Mini Sight, Shield Mini Sight and Jpoint Sight products.

In a third aspect of the invention there is provided a firearm including the reflector sight assembly of the second aspect.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying schematic drawings of which:.

A reflector sight <NUM> according to the example embodiment of the invention (<FIG>) comprises a housing <NUM> on a base <NUM>. The base <NUM> has a roughly rectangular footprint (i.e. the two-dimensional surface area of the underside of the base).

In the present example embodiment, the footprint of the sight <NUM> (as defined by the size and shape of the underside of the base <NUM>) is of a standard size known in the industry. The sight <NUM> of the present example embodiment of the invention can therefore be interchanged on a firearm slide, with other existing sights which have been manufactured to have the same footprint, for example using a common mount. In the present example embodiment, the sight base has a maximum length of <NUM>, and a maximum width of <NUM>. The sight base is significantly smaller than has previously been realised for a closed sight. The sight of the present example embodiment provides a closed sight having associated benefits of durability and all-weather performance, which is comparatively lightweight, which in an advancement on sights of the prior art, can fit onto existing mounting plates designed for small, open sights.

In the example embodiment, the housing <NUM> comprises two opposing upstanding side walls <NUM> and a flat roof <NUM> extending therebetween. The side walls <NUM> are approximately trapezoidal in shape, extending substantially perpendicularly up from the base <NUM>. The trapezoidal side walls <NUM> have a steeply inclined front portion <NUM>, and a shallowly inclined rear portion <NUM>. The roof <NUM> is substantially horizontal, opposing the substantially horizontal plane of the base <NUM>. The housing <NUM> further comprises a front window (not shown in <FIG>), extending down from the front edge <NUM> of the roof <NUM> to the base <NUM>. The housing <NUM> further comprises a rear window <NUM>, extending down from the rear edge <NUM> of the roof <NUM> to the base <NUM>. The rear window <NUM> extends in a substantially perpendicular direction between the base <NUM> and roof <NUM>. The front window (not shown in <FIG>) is angled with respect to the base <NUM>.

The base <NUM> is notionally split into a rear portion <NUM> and a front portion <NUM>. The roof <NUM> extends over the front portion <NUM> of the base <NUM> (but in the present example embodiment of the invention, not over the rear portion <NUM> of the base <NUM>). The side walls <NUM> of the sight <NUM> run adjacent both the front <NUM> and rear <NUM> portions of the base <NUM>. The side walls <NUM> slope down to meet the rear bottom edge <NUM> of the sight <NUM>. The rear parts of the side walls <NUM> (i.e. the parts of the side walls above the rear portion <NUM> of the base <NUM>) effectively define a triangular wing on either (left and right hand) side of the sight <NUM>. The side walls <NUM> therefore, help to protect the rear portion <NUM> of the sight <NUM> from damage.

The front portion <NUM> of the base <NUM> comprises a bridge <NUM> (i.e. a hollow raised portion) protruding up from the top surface of the base <NUM>. The bridge <NUM> is positioned centrally across the width of the sight <NUM>, and towards the rear of the front section <NUM> of the base, with its front end coplanar with the rear window <NUM>.

The bridge <NUM> is elongate with an approximately rectangular cross-section, which varies along the length of the bridge. The cross sectional area of the bridge <NUM> is smaller towards the rear of the sight <NUM> and larger towards the front of the sight <NUM>. The bridge <NUM> comprises a substantially flat roof, with substantially flat sides, and rounded corners.

Extending vertically through the rear portion <NUM> of the base <NUM> of the sight <NUM> are two holes <NUM> for receiving mounting screws, whereby the sight <NUM> can be screwed onto a mount (not shown) or directly to a firearm slide. The length of the sight has been considerably shortened by positioning the mounting holes <NUM> forwards of the bridge <NUM>. This has not been easily accomplished and has required a re-design of the entire interior of the sight <NUM>. In an advantage over sights of the prior art, the present invention provides a sight which is robust and weather-proof yet is compact enough to fit onto existing mounts/ slides machined for smaller, open sights.

Extending vertically through the rear portion <NUM> of the base <NUM> is an adjustment mechanism <NUM> for calibrating the sight <NUM> during use (to centre the reticule and/or ensure co-witness with the iron sights where necessary). The adjustment mechanism <NUM> of the present example embodiment is of a type described in patent <CIT>, and not discussed further herein.

In the present example embodiment, the upper surface of the roof <NUM> comprises two circular locating indents <NUM>, providing locating points onto which an accessory (not shown) may be mounted. The sight <NUM> also comprises, above the rear window <NUM>, two fixing holes <NUM> for receiving screws whereby the accessory can be removably attached to the sight. The fixing holes <NUM> are arranged perpendicularly to the locating indents <NUM>. Such an accessory may include a flip-up cover, torch, laser sight, secondary sight, additional battery, set of roll bars, honeycomb filter, solar charger, night vision cover or other accessory. Thus a more compact closed sight is provided without compromising functionality. Through enabling bolt-on accessories, the sight provides the functionality of a much larger sight.

Looking from the rear, the left-hand side wall <NUM> of the sight <NUM> incorporates a switch <NUM> on its outer face, for adjusting the brightness of the reticle. The righthand side wall <NUM> incorporates a battery on its outer face (not shown in <FIG>).

Within the housing <NUM> is a chamber <NUM> (<FIG>). The chamber <NUM> is enclosed by the roof <NUM>, the side walls <NUM>, the front window, the rear window <NUM> and the base <NUM>. The bridge <NUM> defines an interior tunnel <NUM> which enables the passage of light therethrough (<FIG>, <FIG>). The bridge <NUM> and the base <NUM> together enclose the tunnel <NUM>. The tunnel <NUM> extends down beneath the upper surface <NUM> of the front portion <NUM> of the sight <NUM>. The tunnel <NUM> slopes through the base <NUM> of the sight <NUM>, towards the bottom front edge <NUM> of the sight <NUM>. An LED <NUM> is mounted at the rear end of the tunnel <NUM> and positioned to direct a beam of light up through the tunnel <NUM> and into the chamber <NUM> of the sight <NUM>, where it reaches a convex lens <NUM>. As is known in the art, the LED <NUM> is positioned at the focal point of the lens <NUM>, such that the light is reflected back in a parallel beam from the lens <NUM> to the user's eye (creating an infinity image of the reticule over the target).

The rear opening of the bridge <NUM> is covered by a clear viewing panel <NUM>, enabling the user to look through the tunnel <NUM>. In the present example embodiment the chamber <NUM> is sealed (meaning watertight). The chamber <NUM> is sealed above by the roof <NUM>, below by the base <NUM>, at the front by the front window <NUM> (and the lens <NUM>), on both sides by the side walls <NUM>, and at the rear by the rear window <NUM> and bridge <NUM> together with the viewing panel <NUM>. In another example embodiment, there may be no viewing panel <NUM>, and the tunnel <NUM> may instead be open at its rear end, meaning that the chamber is not sealed, but still protected by way of the roof <NUM>, side walls <NUM>, front and rear windows <NUM>, <NUM>, and base <NUM>.

If the bridge <NUM> were not present, due to the relatively short length of the sight <NUM> (compared to other closed sights) and the location of the mounting holes forwards of the LED, the light beam emitted from the LED light source would not reach the lens, as it would be obstructed by the base <NUM>.

In use, when the sight <NUM> of the present example embodiment is mounted on a firearm having no iron sight, the user relies on the reticle alone for sighting a target (<FIG>). The user can make use of the tunnel for sighting the target, locating the reticle in the viewing panel <NUM>, thus providing a co-witness between the bridge <NUM> and lens <NUM>. However, when the sight <NUM> is mounted on a firearm having an iron sight, there is also an option of aligning the iron sights <NUM> with the lens and viewing panel <NUM>, providing a further co-witness for ease of sighting the target (<FIG>).

In the present example embodiment, the bridge <NUM> (<FIG>) is formed integrally with the base <NUM> of the sight <NUM>. The bridge <NUM> has an approximately rectangular cross-section (i.e. a width and a height) which varies along its length. The bridge <NUM> is sufficiently big to enable a user to look through the tunnel <NUM> formed by the bridge <NUM>, yet not so big that it obstructs too much of the rear window <NUM>. In the present example embodiment, the bridge <NUM> has a maximum external width, w of approximately <NUM>-<NUM>, and a maximum internal width, w' of approximately <NUM>-<NUM>. The bridge <NUM> has a maximum external height, h of approximately <NUM>-<NUM>, and a maximum internal height, h' of approximately <NUM>-<NUM>.

The bridge <NUM> in the present example embodiment has a roof and sides (together, taken to be the walls of the bridge). The walls of the bridge <NUM> are of a thickness of approximately <NUM>-<NUM> for providing an optimal balance between durability and minimising obstruction of the user's view through the rear window. During use, since the sight <NUM> is used with both eyes open to view the reticle over the target, the walls of the bridge become almost invisible to the user, and the reticle remains in view (superposed over the bridge). The bridge <NUM> obstructs approximately <NUM>-<NUM>% of the external surface area of the rear window <NUM> of the sight <NUM>.

As has been described above, the bridge <NUM> is tapered, having a larger (i.e. wider and taller) end <NUM> adjacent the rear window <NUM>, and a smaller (shorter and narrower) end <NUM> towards the rear of the sight <NUM> (<FIG>). The bridge <NUM> is thus shaped to facilitate the passage of the emitted light beam, whilst presenting the minimum possible obstruction in the field of view. The roof <NUM> of the bridge <NUM> stops short of the full depth, d, of the bridge <NUM>. In the example embodiment, the maximum depth of the bridge, d, is approximately <NUM>. The rear edge of the bridge is angled back with respect to the base <NUM>. The bridge comprises a roof <NUM> and side walls <NUM>. The viewing panel <NUM> is angled back with respect to the base <NUM>. The bridge side walls <NUM> extend further towards the rear than the bridge roof <NUM>. The sloping of the rear edge of the bridge <NUM> helps to minimise the obstruction of the field of view by the bridge <NUM>.

The underside <NUM> of the base <NUM> (<FIG>) includes, in addition to the mounting holes <NUM>, four locating recesses <NUM> for locating corresponding locating pegs in a sight mounting plate (not shown).

To mount the sight <NUM> on a firearm, the sight <NUM> is screwed onto a mounting plate (not shown). Mounting plates may be separate components or may be machined into a firearm slide at manufacture. A single mounting plate can typically accommodate a number of different sights all having the same footprint (i.e. having the same size and shape of base and appropriate holes/recesses).

In an advantage over firearms and sight assemblies of the prior art, the present invention provides a closed sight which by being designed to function with a significantly smaller footprint, has been made to match an existing footprint of a smaller open sight. The sight of the present invention can therefore be quickly and easily interchanged with other (open) sights. The closed sight can be swapped with the open sight, without requiring structural modifications of the mounting plate or slide.

In a further advantage, through the use of a suitable adjustment mechanism <NUM> such as the one described in UK patent publication no. <CIT>, the sight <NUM> of the present example embodiment can be positioned relatively low down on the firearm. Thus, the process of calibrating the sight to find a co-witness between the bridge, the lens and the iron sights (when present) is made simpler and easier.

Claim 1:
A reflector sight (<NUM>) for a firearm, the sight comprising:
a base (<NUM>);
a housing (<NUM>) arranged on the base, together defining an inner chamber (<NUM>), the housing comprising a roof (<NUM>), two or more sides (<NUM>), a front window (<NUM>) and a rear window (<NUM>); and
a light source (<NUM>); whereby the base comprises a bridge (<NUM>) defining a tunnel (<NUM>) therethrough; characterised in that the sight is a closed sight, wherein the inner chamber is sealed by a combination of the base, the roof of the housing, the sides of the housing and the front and rear windows of the housing, together with the bridge; and
wherein the light source is arranged with respect to the base to emit light through the tunnel and into the chamber.