GB2504466A

GB2504466A - Weapon accessory mounting bracket

Info

Publication number: GB2504466A
Application number: GB201211956A
Authority: GB
Inventors: Mark Jones
Original assignee: Qioptiq Ltd
Current assignee: Qioptiq Ltd
Priority date: 2012-07-05
Filing date: 2012-07-05
Publication date: 2014-02-05
Anticipated expiration: 2032-07-05
Also published as: GB2504466B; GB201211956D0

Abstract

A weapon accessory mounting bracket comprises a main body 1 with a jaw 2, and a clamp block 3 with a jaw 4 facing the jaw 2. The main body 1 and the clamp block 3 may be urged together by rotating a cam lever 7, allowing the bracket to be mounted on a weapon accessory rail such as a Picatinny rail. The jaws 2, 4 are biased towards each other by a resilient member such a coil spring 11. This allows the bracket to be mounted to the rail and prevents it from falling off while the user moves his hand to the cam lever 7 to lock the bracket in place. In an embodiment, the closing bias of spring 11 is countered by an opening bias supplied by two coil springs 8. Unless cammed together, the jaws 2, 4 thus float in a correct, partially open position and are able to receive an accessory rail at any time. The mounting arrangement allows accessories to be attached or detached at speed, under stress, in extreme conditions or with the user encumbered by protective clothing.

Description

WeaDon Accessory Mounting Bracket

Field of the invention

The present invention relates to a weapon accessory mounting bracket of the kind that is used to mount weapon accessories such as optical sights to weapons such firearms.

Background

Weapons such as firearms, bows, non-lethal projectile weapons and directed energy weapons are increasingly being fitted with weapon accessories. Such accessories include optical sights, support structures such as bipods or foregrips for long arms, fibre-optic or digital cameras, night vision or thermal imaging equipment, tactical lights and laser aiming modules. Weapons often have one or more accessory rails for this purpose, either cut into the frame of the weapon or as bolt-on additions.

Such rails usually lie against the weapon so as to provide a dovetailed protrusion, and generally run parallel to the barrel along the frame of the weapon.

Weapon accessory mounting brackets for mounting a weapon accessory to such a rail are known in various forms. A common form used in civilian sporting or hunting shooting consists of a pair of counterposed plates, each plate having two indentations, one to accommodate one side of the accessory rail and the other to accommodate one side of the accessory. A bolt runs through the plates between the indentations, and by tightening the bolt the two plates are forced together to secure both the accessory and the accessory rail. While this system provides a cheap and easy to use bracket for civilian shooters, it can take considerable time to loosen or tighten the bolt to detach or attach the accessory. In military applications, accessories may have to be attached or detached at speed, under stress, in extreme conditions or with the user encumbered by protective clothing. In such situations the slow and fiddly process of attaching/detaching the above bracket is unsuitable.

An existing bracket for military use is attached to the weapon accessory by conventional means such as bolts. The bracket has a pair of jaws which are biased to an open position to receive the accessory rail of a weapon. The rail is placed between the jaws, which are then closed and secured by a cam lever. While the use of a cam lever in this bracket offers a fast attachment mechanism, attaching the bracket in non-ideal circumstances can be difficult. To attach the bracket the user must hold the weapon in one hand and place the bracket on the accessory rail with the other. They must then balance the bracket on the rail while moving their hand round to the cam lever to secure the bracket in place. Attempting to attach the bracket while wearing gloves, travelling in a vehicle or under time pressure risks the bracket falling to the floor and damaging itself or the weapon accessory. The same problem occurs when attempting to detach the bracket. After rotating the cam lever to release it, the user must balance the bracket on the weapon while moving their hand from the cam lever to the body of the bracket to grasp it.

It is an object of the present invention to obviate or mitigate at least one of the aforesaid disadvantages, and/or to provide an improved or alternative weapon accessory mounting bracket.

Summary

According to a first aspect of the present invention there is provided a weapon accessory mounting bracket comprising: a first body with a first jaw; a second body with a second jaw which is counterposed to the first jaw, the first body and the second body being movable with respect to one another between a closed position and an open position; and a locking mechanism arranged to urge the first body and the second body towards one another when engaged, wherein the first body and second body are biased towards each other from the open position.

To attach the bracket to the accessory rail of a weapon, the bracket is placed on the weapon so that the rail is inserted between the jaws. Inserting the rail between the jaws forces them apart, which moves the first body and the second body to the open position. Because the first body and second body are biased towards each other from the open position, once the widest part of the rail passes through the jaws the first and second bodies (and therefore the jaws) are forced towards each other again. This at least partially closes the jaws around the accessory rail, so the rail cannot be withdrawn again without significant external influence (such as the user actively pulling the rail and the bracket apart). The bracket is therefore retained on the rail until the locking mechanism is engaged to secure it, without the user having to rely on balancing the bracket in place. Similarly, when the locking mechanism is disengaged so that the bracket can be removed, the first and second bodies being biased towards each other causes the jaws to remain at least partially closed around the rail and prevent its inadvertent removal. When the user wishes to detach the bracket, the first body and second body can be forced apart against their bias so that the rail can be removed from between the jaws.

The first body and second body may be biased towards each other by one or more resilient members.

The one or more iesilient members may be splings.

The first body and second body may be biased towards each other by one or more magnets.

The weapon accessory mounting bracket may also comprise a bar which projects from the first body, through a bore in the second body.

The bar may also be received through a bore in the first body, and terminate in an enlarged head.

The locking mechanism may comprise a cam lever configured such that rotation of the lever in one direction cams the second body away from the cam lever, and rotation of the lever in the other direction allows the second body to move back towards the cam lever.

The second body and first body may be biased towards each other from the open position to a partially open position.

The first body and second body may be biased away from each other from the closed position.

The second body and first body may be biased away from each other by one or more resilient members.

The one or more resilient members which bias the second body and first body away from each other may be springs.

The second body and first body may be biased away from each other by one or more magnets.

The one or more resilient members or magnets which bias the second body and first body away from each other may be housed within a blind bore in either the first body or the second body, and act upon a piston that projects into the blind bore from the other of the first body and the second body.

The force biasing the second body and the first body away from each other may be applied at two points on substantially opposite sides of the bar.

The bracket may further comprise a resilient buffer arranged to be deformed when the locking mechanism is engaged such that the restorative force from the resilient buffer continuously urges the second body and first body towards each other while the locking mechanism is engaged.

The one or more resilient members which bias the first body and second body towards each other may be received within a cup housing, at least one of the resilient members protruding from the cup housing when the second body is in the partially open position, the resilient members being contained within the cup housing when the locking mechanism is engaged.

A distal end of one or both of the first jaw and the second jaw may have a ramped portion which is slanted towards the other of the first jaw and the second jaw.

The first body may have one or more additional first jaws and the bracket may have one or more additional second bodies, each second body having a second jaw which is counterposed to a first jaw.

The or each pair of counterposed first and second jaws may be shaped and spaced to receive a NATO accessory rail, a Picatinny rail or a Weaver rail mount.

According to a second aspect of the invention there is provided a weapon accessory including a weapon accessory mounting bracket according to the first aspect of the invention.

Throughout this specification, the term "comprising" or "comprises" means including the component(s) specified but not to the exclusion of the presence of others. Optional and/or preferred features as set out herein may be used either individually or in combination with each other where appropriate and particularly in the combinations as set out in the accompanying claims. The optional and/or preferred features for each aspect of the invention set out herein are also applicable to any other aspects of the invention, where appropriate.

The described and illustrated embodiments are to be considered as illustrative and not restrictive in character, it being understood that only a preferred embodiment has been shown and described and that all changes and modifications that come within the scope of the inventions as defined in the claims are desired to be protected. In relation to the claims, it is intended that when words such as a," an," at least one," or at least one portion" are used to preface a feature there is no intention to limit the claim to only one such feature unless specifically stated to the contrary in the claim. When the language at least a portion" and/or "a portion" is used the item can include a portion and/or the entire item unless specifically stated to the contrary. For the avoidance of doubt, any reference to one object moving relative to another object is intended to cover either component being stationary while the other moves, or both components moving simultaneously.

Detailed description

Specific embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is an illustrative diagram of a weapon accessory mounting bracket according to an embodiment of the invention; and Figure 2 is a perspective view of the weapon accessory mounting bracket shown in figure 1.

Referring now to the drawings, the attachment mechanism of the weapon accessory mounting bracket according to the described embodiment of the invention is illustrated in partial cross-section view from above in figure la. The bracket has a first body 1 (hereafter referred to as a main body) with a first jaw 2 (hereafter referred to as a body jaw), and a second body 3 (hereafter referred to as a clamp block) with a second jaw 4 (hereafter referred to as a block jaw) which faces the first jaw 2. The main body 1 is adapted to receive a weapon accessory such as night vision or thermal imaging equipment, an optical sight, a support structure such as a bipod or foregrip for long arms, a fibre-optic or digital camera, a tactical light or a laser aiming module.

The main body 1 and clamp block 3 are movable with respect to each other between an open position and a closed position. The jaws 2, 4 are more distant from one another when the main body 1 and clamp block 3 are in the open position than when they are in the closed position, and similarly the jaws 2, 4 are closer together when the main body 1 and clamp block 3 are in the closed position. The main body 1 and clamp block 3 therefore function as a clamp to attach the bracket to an accessory rail (such as a NATO accessory rail, a Picatinny rail or a Weaver rail mount) of a weapon. The clamp block 3 and main body 1 can be braced together and urged towards each other to secure the clamp by a locking mechanism. The locking mechanism is provided by a cam lever 7 on the opposite side of the clamp block 3 to the main body 1, connected by a cylindrical bar 5 running through bores in the main body 1 and clamp block 3 to an enlarged head 6 on the opposite side of the main body 1 to the clamp block 3. As outlined below, by rotating the cam lever 7 the available distance along the bar 5 between the cam lever 7 and the enlarged head 6 is decreased, so the clamp block 3 and the main body 1 are urged together. The locking mechanism utilising the bar provides a guide rail for movement of the main body 1 and clamp block 3. It also serves as an attachment point for the locking mechanism.

In the illustrated embodiment, the portion of the bar 5 which runs across the main body 1 between the body jaw 2 and block jaw 4 is exposed, that is to say that it stands out from the main body 1 between the jaws 2,4. While in the illustrated embodiment the entire circumference of the bar 5 is exposed between the jaws, in alternative embodiments the bar 5 may run through a groove in the main body 1 such that only a segment of the bar stands out from the main body 1. The bar 5 (or a segment of the bar 5) being exposed allows it to be received in an orthogonal groove in the rail, which may prevent the bracket from sliding longitudinally along the rail before the locking mechanism is engaged to secure it.

The clamp block 3 and the main body 1 are biased towards each other from the open position. In the illustrated embodiment they are biased by a resilient member in the form of a coil spring 11. A resilient member such as a coil spring may provide a simple, reliable and low maintenance source of the required motive force.

In this embodiment the spring 11 biases the clamp block 3 and the main body 1 together from the open position to a partially open position (that is to say a position in which the jaws 2, 4 are closer together than when the clamp block 3 and main body 1 are in the open position, but further apart than when the clamp block 3 and main body 1 are in the closed position).

The attachment mechanism of the bracket will now be described with reference to figures lb-le, each of which is a partially cross-sectional view of the bracket, viewed from one end (it should be noted that the shapes of the rail 10 and of each of the jaws 2, 4 are purely illustrative and schematic, and may not correspond to the actual shapes used when putting the invention into effect). Because the jaws 2, 4 are not biased to the open position, to attach the bracket the accessory rail 10 must be actively placed between the jaws 2, 4 of the bracket. This can be done in one of two ways. Firstly, as shown in figure 1 b, the block jaw 4 can be hooked onto one side of the rail 10 before sliding the rail or the main body 1 sideways (or the body jaw 2 can be hooked onto the rail before sliding the clamp block 3 sideways). This moves the main body 1 and the clamp block 3 apart to the open position, as shown in figure ic, at which point the rail 10 can be fully inserted between the jaws 2, 4.

Alternatively, since the main body 1 and the clamp block 3 are in the partially open position, the jaws 2, 4 are far enough apart that the top ramps 13 of the accessory rail 10 can be used to cam the jaws apart by pressing the bracket between them. The jaws 2, 4 being cammed apart forces the main body 1 and clamp block 3 to the open position and allows the rail to fully enter the jaws 2, 4. In order that less force is required to cam the jaws 2, 4 apart should this method of attachment be utilised, the jaws 2, 4 of the illustrated embodiment each have a ramped portion 14 which is slanted towards the opposing jaw. The ramped portions also provide a hollow which can rest on the rail 10 prior to attachment, which allows the user to feel when the bracket is in the correct position for attachment before attempting to secure it, should they need to attach the bracket when in the dark or with their vision obscured (such as by smoke or dust, or by protective equipment such as a gas mask).

When the rail 10 has been fully inserted between the jaws 2, 4 by either of the above techniques, the spring 11 continues to urge the clamp block 3 and main body 1 (and therefore the jaws 2, 4) together towards the partially open position. With the main body 1 and clamp block 3 in the partially open position, the jaws 2, 4 are sufficiently close together to prevent removal of the rail from between them without the application of a significant external force. When the main body 1 and the clamp block 3 are in the partially open position, the jaws may or may not be spaced further apart than the spacing necessary to accommodate the rail 10 between them, but in either case they are sufficiently close together to hold the bracket on the rail 10 to

S

prevent it falling off the weapon while the user is moving their hand to the cam lever 7 to lock the bracket in place. If the spacing of the jaws 2, 4 necessary to accommodate the rail 10 is smaller than their spacing when the main body 1 and clamp block 3 are in the partially open position, the main body 1 and the clamp block 3 will remain in the partially open position and the bracket will still be retained on the rail (albeit with a degree of rattle') since the jaws 2, 4 are not far enough apart to allow the rail to be removed from between them without input from the user.

Alternatively, if the spacing of the jaws 2, 4 necessary to accommodate the rail 10 is larger than their spacing when the main body 1 and clamp block 3 are in the partially open position (as shown in figure ld), when the rail lOis between them the jaws 2,4 will be held apart by the rail 10 and will squeeze it between them (due to the biasing force provided by spring 11) and hold the bracket in place.

With the rail 10 between the jaws 2, 4, by rotating the cam lever 7 to engage the locking mechanism, the distance between the head 6 of the bar 5 and the cam lever 7 is gradually decreased. The head 6 of the bar 5 braces against the side of the main body 1 and the cam lever 7 braces against the clamp block 3, and the two components are urged together to clamp the jaws onto the accessory rail 10 and secure the bracket in place (as shown in figure le). If the spacing of the jaws 2, 4 necessary to accommodate the rail 10 is smaller than their spacing when the main body 1 and clamp block 3 are in the partially open position, the locking mechanism will cam the main body 1 and clamp block 3 together from the partially open position until the jaws 2, 4 contact the sides of the rail, and then continue to urge the main body 1 and clamp block 3 together to clamp the jaws 2, 4 onto the rail 10. If the spacing of the jaws 2, 4 necessary to accommodate the rail 10 is larger than their spacing when the main body 1 and clamp block 3 are in the partially open position (as shown in figure id), then the lever 7 will not move the clamp block 3 and main body 1 any further together and will simply urge them together in their current positions to clamp the jaws 2, 4 onto the rail 10.

As well as the main body 1 and clamp block 3 being biased together from the open position to the partially open position, in the illustrated embodiment they are also biased apart from the closed position to the partially open position. The biasing force is provided by two resilient members in the form of coil springs 8, each of which is housed in a blind bore in the main body 1 and acts on a piston 9 which projects into the blind bore from the clamp block 3. The main body 1 and the clamp block 3 being biased apart from each other from the closed position towards the partially open position ensures that when not under external influence, the main body 1 and the clamp block 3 remain in the partially open position. This maintains the jaws 2, 4 in the correct position to receive an accessory rail 10 at any time. This limits the preparation time and user concentration needed to attach the bracket, because the user does not have to move the clamp block 3 and main body 1 apart if they have slipped to the closed position. The pistons projecting from the clamp block 3 into the main body 1 also ensure that the clamp block 3 and main body 1 remain in rotational alignment (i.e. the main body 1 and the clamp block 3 cannot rotate significantly relative to one another about the axis of the bar), again ensuring that the jaws 2, 4 remain receptive to the insertion of an accessory rail 10 at any time. In addition, the force biasing the main body 1 and clamp block 3 apart being applied at two points, one on either side of the bar, ensures that the main body 1 and the clamp block 3 remain square to each other so that the jaws 2, 4 remain parallel.

To disengage the locking mechanism to remove the bracket, the cam lever 7 is rotated in the opposite direction to the direction that was used to engage the locking mechanism. This increases the available distance between the head 6 of the bar and the cam lever 7, allowing the main body 1 and clamp block 3 (and thus the jaws 2, 4) to move apart. Whether they move apart at all without the user's input when released is also dependent on whether the spacing of the jaws 2, 4 necessary to accommodate the rail 10 is larger or smaller than their spacing when the main body 1 and clamp block 3 are in the partially open position. If the spacing of the jaws 2, 4 necessary to accommodate the rail 10 is larger than their spacing when the main body 1 and clamp block 3 are in the partially open position then the clamp block 3 and main body 1 will not move autonomously when the cam lever is disengaged. If, on the other hand, the spacing of the jaws 2, 4 necessary to accommodate the rail 10 is smaller than their spacing when the main body 1 and clamp block 3 are in the partially open position, the clamp block 3 and main body 1 will move to the partially open position under the influence of the springs 8. In either case, the clamp block 3 and the main body 1 remain closer together than the spacing that would allow the rail to exit the jaws 2, 4 without influence from the user, so again the bracket is prevented from falling off the weapon. To remove the bracket after the locking mechanism has been disengaged, the rail 10 must be forced out of the jaws by the user. By pulling the bracket and weapon apart, the bottom ramps 15 of the accessory rail 10 contact an internal surface 16 on each of the jaws 2, 4 and cam the jaws 2,4 apart, moving the clamp block 3 and the main body 1 to the open position and releasing the rail 10. When the bracket has been removed from the rail 10, the main body 1 and clamp block 3 move back to the partially open position under the influence of spring 11.

Throughout its rotation, the cam lever 7 is held in alignment with respect to the clamp block 3 (which, in turn is held in alignment by the pistons 9 as outlined above) via a ridge 17 on the clamp block which is received within a circumferential groove 18 in the cam lever. The alignment of the cam lever 7 being constant allows the user to know where it will be at any time, allowing them to locate it easily rather than having to take their attention away from other tasks to visually locate it or having to search for it by feel. An additional feature of the cam lever 7 is that it is shaped to exhibit an over-centre bias, that is to say that the lever 7 is bistable with the stable positions being at either end of the lever's range of motion. In other words, moving the lever 7 in either direction must be performed against mechanical bias until a certain point is reached. Beyond this point, the mechanical bias of the lever changes and urges the lever 7 to continue its motion. This over-centre bias ensures that the lever 7 remains in position when the locking mechanism is engaged, minimising the possibility of accidental disturbance of the lever 7 (such as it snagging on clothing or undergrowth) disengaging the locking mechanism. Additionally, the over-centre bias allows the lever 7 to be engaged or disengaged with the flick of a finger rather than it having to be painstakingly rotated through its entire range of motion by the user, making the bracket easier and quicker to engage or disengage. This mechanism also provides both tactile and auditory feedback, which further increases the ease of use and reliability of the bracket.

As outlined above, the spring 11 biases the clamp block 3 and main body 1 towards each other from the open position, as far as the partially open position. In the illustrated embodiment, when the clamp block 3 and main body 1 are at the partially open position the spring 11 is in a relaxed (non-deformed) state, however in other embodiments it may be in a deformed state, its restorative force being counterbalanced by the force (from springs 8) biasing the clamp block 3 and main body 1 away from each other to the partially open position. The spring 11 lies between the head 6 of the bar band the main body 1. This positioning maintains the simplicity of the bracket, ensures that the spring is visible for inspection in the event of a clamp malfunction, and allows maintenance in the field to be straightforward.

The spring 11 is received within a cup housing 19. When in the relaxed position the spring 11 projects from the cup housing 19, and the restorative force from the spring 11 can act on the bar 5 and the main body 1 to bias the clamp block 3 and the main body 1 together to the partially open position. When the cam lever 7 is rotated so that the locking mechanism is engaged, the spring 11 is compressed and lies fully within the cup housing 19. With the spring 11 contained within the cup housing 19 the clamping force produced through the locking mechanism can be applied over a shod range of motion, whereas if the clamping force had to be applied through the spring 11 a substantially larger range of motion could be necessary in order to accommodate its compression. The cup housing also shields the spring from the ingress of foreign bodies which could become trapped between coils of the spring and hinder its function.

Additional stability of the locking mechanism 7 is provided by a resilient buffer in the form of two Belleville washers 21 (also known as coned disc springs or conical spring washers), which are positioned between the head 6 of the bar 5 and the side of the main body 1 (along with the spring 11 and the cup housing 19). The restorative force from the buffer continues to urge the clamp block 3 and the main body 1 together while the locking mechanism is engaged, which minimises the possibility of recoil vibration dislodging the cam lever and disengaging the locking mechanism. The buffer also allows less stringent machining tolerances to be used during manufacture while ensuring sufficient clamping force is applied, as it can accommodate slight variations in the proportion of the length of the bar taken up by the clamp block 3, main body 1, etc. The buffer may also allow the mechanism to withstand changes in size of the components due to thermal expansion.

As seen in figure 2, the main body 1 of the bracket has a second body jaw 2 and the bracket has a second clamp block 3 with substantially identical features and connected components to the first, forming a duplicate clamp. The bracket having two clamps allows it to be attached to an accessory rail 10 more securely and with a greater degree of precision of alignment. Utilising multiple clamps may also allow the bracket to maintain functionality should one of the clamps be damaged or accidentally disengaged. In the illustrated embodiment, the two cam levers 7 are aligned in opposite directions so that when they are both rotated to engage their respective locking mechanisms, they point substantially towards each other. This alignment minimises the opportunity for the cam levers 7 to snag on their surroundings, which could unintentionally disengage the locking mechanism.

Numerous modifications to the above described designs may be made without departing from the scope of the invention as defined by the appended claims.

For example, the main body and the clamp block may pivot with respect to one another to open and close the jaws rather than sliding, or they may both pivot and slide. Similarly, the main body and clamp block are not limited to sliding directly towards and away from each other, and may slide in any direction which may open and close the jaws. Additionally, while in the illustrated embodiment both jaws of both pairs of jaws have ramped portions, one or more pairs of jaws may have only one jaw with a ramped portion or may have no jaws with a ramped portion.

Furthermore, the locking mechanism may take a form other than a cam lever.

For instance, it may utilise a ratchet mechanism. In one such embodiment, the locking mechanism comprises a collar on the opposite side of the clamp block to the main body, the collar being slidably mounted on the bar and securable via a ratchet pawl which engages with complimentary ratchet teeth on the bar.

Although the bar is cylindrical in the illustrated embodiment, in alternative embodiments it may have a square, rectangular, ovoid, triangular, pentagonal, hexagonal, heptagonal or octagonal cross section or may have any other suitable shape. Rather than running through the main body and clamp block, the bar may run under, above or to either side of one or both of the main body and the clamp block.

Although in the illustrated embodiment the locking means is on the end of the bar projecting from the clamp block and the enlarged head (along with the spring, cup housing and buffer) is on the end of the bar which projects from the main body, they may each be on the opposite end instead.

In other exemplary embodiments, the main body and clamp block may be biased towards each other to the closed position rather than to the partially open position. They may, in some embodiments, not be biased away from each other at all, or may be biased away from each other to an additional position which lies between the closed position and the partially open position.

The groove and ridge which keep the cam lever in alignment with the clamp block may be the other way round (i.e. the groove being on the clamp block and the cam lever having an annular ridge). There may also be more than one groove and ridge (either with one component having all the grooves and the other all the ridges, or each having both at least one groove and at least one ridge), and one or more of the ridges may each be replaced by one or more projections.

Instead or in addition to the above variations to the aforedescribed embodiment, there may be one or more components in place of spring 11. Each component may be a coil spring, a different type of resilient member such as an elastomeric block, may be a magnet, or may be a different type of spring such as a gas spring, leaf spring, volute spring or Belleville washer. Instead of being located between the head of the bar and the main body, the components may be located in any other suitable location such as between the locking mechanism and the clamp block, or offset from the bar. Instead of the components being received within a cup housing, the bracket may have a different arrangement for preventing excess compression of the components. For example, if the components are springs they may be arranged to reach their solid length at the required point, or if the components are magnets they may be arranged to physically contact the part of the mechanism their magnetic field effects at the required point. The clamp block and main body may be biased together from the open position by any other suitable arrangement.

There may be one or more components in place of either or both of the springs 8. Each component may be a coil spring, a different type of resilient member such as an elastomeric block, a magnet, or a different type of spring such as a gas spring, leaf spring, volute spring or Belleville washer. Additionally, all the components may all be contained in a single blind bore, or in 3, 4 or more, and the blind bores may be in the clamp block with the piston projecting from the main body.

Alternatively, one or more of the components may not be in a blind bore but may instead lie directly between the clamp block and the main body, or may run above, below or on either side of the clamp block and/or main bore. The components may be in a relaxed state when the clamp block and main body are in the partially open position (or the additional position, if applicable), or they may continue to force them apart but be counteracted by the force biasing the clamp block and main body towards each other from the open position. The clamp block and main body may instead be biased apart from the closed position by any other suitable arrangement.

In other embodiments, the resilient buffer may comprise one or more components. Each component may be a Belleville washer, a different type of resilient member such as an elastomeric block, a magnet, or a different type of spring such as a coil spring, gas spring, leaf spring or volute spring. The buffer may be situated between the head of the bar and the main body as in the illustrated embodiment but lie between the cup housing and the main body rather than between the head of the bar and the cup housing. Alternatively it may be situated in a different location such as between the locking mechanism and the clamp block, between the clamp block and the main body, or in any other suitable location. Additionally, there may be more than one buffer, each being at a different location.

In embodiments with more than one clamp there may be one or more additional clamps. Although the main body and one clamp block are biased towaids each other from the open position, the main body and each of the additional clamp blocks may or may not be biased towards each other from the open position (and if so may or may not be biased together to the partially open position). Also, they may or may not be biased apart from the closed position (and if so may or may not be biased apart to the partially open position), and may or may not be securable by locking means. The mechanism by which each clamp block is biased (where applicable) and the locking mechanism by which each is securable (where applicable) may be individual or may be common between two or more clamps.

Where the mechanisms are individual, they may or may not be duplicates of each other. For the avoidance of doubt each of the open, closed, partially open and additional positions may or may not be the same between clamp blocks.

The bracket of the illustrated embodiment is made from anodised aluminium alloy, however in other embodiments it may be made from untreated aluminium alloy, or from steel, stainless steel, titanium, magnesium, a polymer, a composite material or any other suitable material. Additionally, while the description assumes that the bracket is attached to the weapon accessory and the rail to the weapon it is to be understood that this may be reversed, with the bracket mounted on the weapon and clamping onto a rail fitted to the accessory.

Claims

CLAIMS1. A weapon accessory mounting bracket comprising: a first body with a first jaw; a second body with a second jaw which is counterposed to the first jaw, the first body and the second body being movable with respect to one another between a closed position and an open position; and a locking mechanism arranged to urge the first body and the second body towards one another when engaged, wherein the first body and second body are biased towards each other from the open position.
2. The weapon accessory mounting bracket according to claim 1 wherein the first body and second body are biased towards each other by one or more resilient members.
3. The weapon accessory mounting bracket of claim 2 wherein the one or more resilient members are springs.
4. The weapon accessory mounting bracket according to claim 1 wherein the first body and second body are biased towards each other by one or more magnets.
5. The weapon accessory mounting bracket according to any one of the preceding claims wherein the bracket also comprises a bar which projects from the first body, through a bore in the second body.
6. The weapon accessory mounting bracket according to claim 5 wherein the bar is also received through a bore in the first body, and terminates in an enlarged head.
7. The weapon accessory mounting bracket according to any one of the preceding claims wherein the locking mechanism comprises a cam lever configured such that rotation of the lever in one direction cams the second body away from the cam lever, and rotation of the lever in the other direction allows the second body to move back towards the cam lever.
8. The weapon accessory mounting bracket according to any one of the preceding claims wherein the second body and first body are biased towards each other from the open position to a partially open position.
9. The weapon accessory mounting bracket according to any one of the preceding claims wherein the first body and second body are also biased away from each other from the closed position.
10. The weapon accessory mounting bracket according to claim 9 wherein the second body and first body are biased away from each other by one or more resilient members.
11. The weapon accessory mounting bracket according to claim 10 wherein the one or more resilient members of claim 10 are springs.
12. The weapon accessory mounting bracket according to claim 9 wherein the second body and first body are biased away from each other by one or more magnets.
13. The weapon accessory mounting bracket according to any one of claims 10-12 wherein the one or more resilient members or magnets are housed within a blind bore in either the first body or the second body, and act upon a piston that projects into the blind bore from the other of the first body and the second body.
14. The weapon accessory mounting bracket according to any one of claims 9-13, incorporating claim 5, wherein the force biasing the second body and the first body away from each other is applied at two points on substantially opposite sides of the bar.
15. The weapon accessory mounting bracket of any one of the preceding claims wherein the bracket further comprises a resilient buffer arranged to be deformed when the locking mechanism is engaged such that the restorative force from the resilient buffer continuously urges the second body and first body towards each other while the locking mechanism is engaged.
16. The weapon accessory mounting bracket of claim 2 and claim 8, wherein the one or more resilient members which bias the first body and second body towards each other are received within a cup housing, at least one of the resilient members protruding from the cup housing when the second body is in the partially open position, the resilient members being contained within the cup housing when the locking mechanism is engaged.
17. The weapon accessory mounting bracket of any one of the preceding claims wherein a distal end of one or both of the first jaw and the second jaw has a ramped portion which is slanted towards the other of the first jaw and the second jaw.
18. The weapon accessory mounting bracket of any one of the preceding claims wherein the first body has one or more additional first jaws and the bracket has one or more additional second bodies, each second body having a second jaw which is counterposed to a first jaw.
19. The weapon accessory mounting bracket of any one of the preceding claims wherein the or each pair of counterposed first and second jaws are shaped and spaced to receive a NATO accessory rail, a Picatinny rail or a Weaver rail mount.
20. A weapon accessory mounting bracket substantially as hereinbefore described with reference to the accompanying figures.
21. A weapon accessory including a weapon accessory mounting bracket according to any one of the preceding claims.