The invention relates to a security barrier, and a method for operation thereof.
A security barrier or bollard may be used for resisting an unauthorised passage of a vehicle such as a car or lorry. Such barriers typically comprise a housing with a barrier member mounted to it. The housing is typically cast into concrete foundations below ground level. The bather member is arranged to be retractable so that it can be stowed within the housing to allow the vehicle to pass, or deployed to a working position above ground level to prevent or inhibit the vehicle to pass. In the deployed position the barrier member is required to be sufficiently high above ground level to prevent or inhibit the vehicle from passing.
Security bathers are typically provided in two categories. The first category is a high security barrier, or anti-terrorist barrier, that is intended to prevent a vehicle from passing. Such a barrier is robustly constructed and is typically about 1-1.5 metres above ground level. A high security barrier might be used at a road entrance to an airport or an official building, such as a Government building, and is typically able to withstand a crash impact from a car or lorry. The second category of security barrier might be used at a home or work premises to safeguard a car parking space or driveway from being used by another vehicle. Such barriers are relatively less robustly constructed, and may extend up to one metre above ground level.
It is known to provide a security barrier which comprises a wedge-shaped barrier member which is arranged to pivot substantially at ground level about the thin end of the wedge. The barrier member is typically the width of a road and is operable to be stowed in a housing in the ground so that a surface of the wedge is level with the ground. The security member may be deployed above ground so that an uppermost part of the wedge is up to a height of 1.5 metres. Such a security barrier has the problem that when the wedge is stowed in the ground, a deep foundation is required to be used for the housing. It will be appreciated that the depth of the foundation must be at least as deep as the height that the wedge-shape barrier member protrudes from the ground when in the deployed position. Using such a deep foundation is disadvantageous, particularly in an urban environment, because it may interfere with services such as power lines, drains, or communication cables.
In another known arrangement the barrier member comprises a rectangular flat plate having a skirt or bellows. The flat plate is arranged to pivot at ground level about one edge, and the skirt extends between the other three edges of the flat plate and the ground. A problem with such an arrangement is that the flat plate forms an overhang above ground which may represent a safety hazard due to the proximity of the ground as the flat plate moves back to the stowed position.
It is also known to provide a security bollard or post which is moveable between a vertical position above ground and a vertical position below ground. Such an arrangement also has the problem of requiring a deep foundation for a housing for the post, which must be at least as deep as the height of the bollard above ground. In an alternative arrangement the post is telescopic so that the foundations for the housing are not required to be as deep, but such a telescopic post adds cost and complexity. Such security bollards or posts generally represent less of a safety hazard than the flat plate security barrier due to the closer fitment of the bollard or post relative to the ground.
It is further known to provide a security bollard or post which is pivotable below ground level. The post is mounted in a housing having a flap which must be opened before the post can be deployed. Once the post has been deployed the flap must be closed to present a flat surface at ground level for safety reasons. Such arrangements require a relatively shallow foundation for the housing, but have the disadvantage that an additional step of opening the flap is required to deploy the post and to create a flat surface after the post has been deployed. Such arrangements also add cost and complexity.
It is broadly an object of the present invention to address one or more of the above mentioned disadvantages of previously known security barriers.
What is required is a way of readily permitting a security barrier to be deployed and retracted, which may reduce or minimise at least some of the above-mentioned problems.
According to a first aspect of the invention, there provided a security barrier comprising a support and a barrier member movable relative to the support between a stowed position and a deployed position, the support having an upper part for positioning substantially at ground level, wherein the barrier member is rotatably mounted relative to the support such that an axis of rotation of the barrier member is above the upper part.
Such a security barrier provides the advantage that the barrier member can be located shallowly in the ground in the stowed position relative to the height of the barrier member when it is deployed from the support. Such an advantage is provided by the axis of rotation that is above the upper part. The upper part may be the uppermost part of the support on which a vehicle can drive or a person can walk. The security barrier can be more easily installed in the ground because relatively shallow concrete foundations can be used which are less likely to interfere with services such as power lines, drains, or communication cables. Furthermore, a security barrier so arranged may provide the advantage of a relatively close fitment of the barrier member relative to the support from which the barrier member is deployed.
Preferably at least a part of the barrier member is curved or circular. In a preferred embodiment the barrier member has a shape which is a part of an annulus. Such a curved barrier member further allows it to be deployed and stowed so that the depth of the barrier member below ground is shallow relative to the height of the barrier member above ground.
Preferably the support comprises a housing. Preferably the housing has an aperture through which the barrier member is operable to be stowed and deployed. The provision of a curved barrier member permits a close fitment to the aperture which may improve the safety of operation of the security barrier, and may inhibit debris from entering a gap between the barrier member and the aperture.
The aperture may be provided near to one end of the housing. In this arrangement the barrier member is deployed near to one end of the housing, which may improve the resistance of the security barrier from being forced out of the ground in the event of crash impact from a vehicle.
Preferably the aperture is provided with at least one adjustment part for adjusting the size of the aperture. Preferably the at least one adjustment part comprises a plate which is adjustably secured to the housing. The provision of an adjustable aperture further assists with the provision of a close fitment of the barrier member in the aperture.
Preferably the upper part comprises an upper surface of the support. Preferably the upper surface is substantially at ground level, in use. This has the advantage that a vehicle can drive on the upper surface, or a person can walk on the upper surface.
Preferably the barrier member is mounted to the support with at least one wheel to provide said rotatable mounting of the bather member relative to the support. Preferably a rolling surface of the at least one wheel engages a surface of the barrier member. In this manner the barrier member may rest on the at least one wheel.
Preferably the barrier member has a first bearing surface and the support has a second bearing surface, the bearing surfaces arranged to abut each other when the barrier member is in the deployed position. Such an arrangement has the advantage of inhibiting the barrier member from being forced out of the support in the event of a crash impact from a vehicle. Such an arrangement also provides a stop so that the barrier member is fully deployed in a particular position.
Preferably at least one of the bearing surfaces comprises at least one plate connected to the support or the barrier member.
Preferably the support includes at least one attachment region for location of at least one reinforcing bar. The at least one attachment region may be a hole of the support. Preferably the security barrier further includes opposing attachment regions at either side of the support. Using at least one reinforcing bar has the advantage of improving the connection between the support and a concrete foundation in which the support may be cast. This may further assist with inhibiting the support from lifting out of the ground in the event of a crash impact from a vehicle.
Preferably at least a part of the bather member is substantially level with the upper part when the bather member is in the stowed position. This provides the advantage that a vehicle can drive on the part, and a person can walk on the part when the barrier member is in the stowed position.
The security barrier may further including a drive device operable to provide a rotatable movement of the mounting member relative to the support. Preferably the drive device comprises at least one actuator. Preferably the at least one actuator is a linear actuator having an actuator arm.
Preferably the drive device is attachable to the barrier member with a connection device. Preferably the connection device comprises a first part for releasable connection to the barrier member. Preferably the connection device comprises a second part for releasable connection to the drive device. Preferably the first and second parts are releasably connectable to each another.
In one embodiment a depth of the barrier member in the stowed position below the upper part relative to a height of the barrier member above the upper part in the deployed position has a ratio in the range 25-55%. In a preferred embodiment the depth of the barrier member in the stowed position below the upper part relative to the height of the barrier member above the upper part in the deployed position has a ratio of substantially 40%.
In one embodiment a dimension of the axis of rotation above the upper part is between 10%-95% of a dimension of the radius of curvature of the barrier member. In a preferred embodiment the dimension of the axis of rotation above the upper part is between 65%-90% of the dimension of the radius of curvature of the barrier member. In a still further embodiment the dimension of the axis of rotation above the upper part is substantially 75% of the dimension of the radius of curvature of the barrier member. Preferably the axis of rotation is substantially parallel to the ground.
Preferably the support is provided with at least one ground anchor. Preferably the at least one ground anchor comprises at least a portion of the housing. Preferably the portion is tapered away from the upper part towards a free end of the portion which is below the upper part. The at least one ground anchor may comprise a foot of the support. The provision of a ground anchor may further resist the security barrier from being forced out of the ground in the event of a crash impact from a vehicle.
According to a second aspect of the invention there is provided a method of operating a security barrier comprising a support and a barrier member, the support having an upper part for positioning substantially at ground level, the method including:
Such a method of operating a security barrier provides the advantage that the barrier member can be located shallowly in the ground in the stowed position relative to the height of the barrier member when it is deployed from the support. Such an advantage is provided by the axis of rotation that is above the upper part. The upper part may be uppermost of the support on which a vehicle can drive or a person can walk. The security barrier can be more easily installed in the ground because relatively shallow concrete foundations can be used which are less likely to interfere with services such as power lines, drains, or communication cables.
According to an alternative characterisation of the invention there is provided a security barrier comprising a support and a barrier member movable relative to the support between a stowed position and a deployed position, wherein the barrier member is pivotably mounted relative to the support such that a pivot axis of the barrier member is above the support.
According to another alternative characterisation of the invention there is provided a security barrier comprising a support and a barrier member movable relative to the support between a stowed position and a deployed position, wherein the security barrier has a mechanism operable to permit the barrier member to be moved horizontally and vertically relative to the support as it is moved between the stowed position and a deployed position.
According to another alternative characterisation of the invention there is provided a security barrier comprising a support and a barrier member, the support having an upper part for positioning substantially at ground level, the barrier member movable relative to the support between a stowed position where at least a part of the barrier member is below the upper part and a deployed position where at least a part of the barrier member is above the upper part, wherein the barrier member is rotatably mounted relative to the support such that an axis of rotation of the barrier member is above the upper part.
According to another alternative characterisation of the invention there is provided a security barrier comprising a support and a barrier member movable relative to the support between a stowed position and a deployed position, the support having an upper part for positioning substantially at ground level, wherein the barrier member comprises a pendulum such that an axis of pivoting of the barrier member is above the upper part.
According to another alternative characterisation of the invention there is provided a security barrier comprising a support and a barrier member movable relative to the support between a stowed position and a deployed position, wherein the barrier member comprises a pendulum requiring an increasing force to move it from the stowed position.
Other features of the invention will be apparent from the following description of preferred embodiments shown by way of example only with reference to the accompanying drawings, in which;
The top plate 22 has a first aperture 28 at a forward part of it through which a barrier member 30 is shown to be deployed. There is a gap of about 5 mm to 10 mm between the barrier member 30 and the top plate 22. The barrier member 30 is curved and is shown to emerge from the inner space 26 through the first aperture 28. The barrier member 30 may alternatively be termed a bollard. The first aperture 28 has a front closure plate 32 and rear closure plate 34 which are provided at the same level as the top plate 22. The front and rear closure plates 32, 34 are movable to provide a close fitment of the barrier member 30 at a front and back region of the first aperture 28. The top plate 22 has a second aperture 36 at a rearward part of it. The second aperture 36 has a back closure plate 38 which is provided at the same level as the top plate 22. The back closure plate 38 is removable for maintenance and adjustment of a drive mechanism 78 and rollers 88, 90, 92 shown in
In
Also shown is a longitudinal line 54 which represents the position of a reinforcing bar (not shown), also known as a rebar, through holes 56, 58 in the opposing anchors 42, 48. The reinforcing bar is a steel bar having a diameter of 32 mm that is commonly used for reinforced concrete foundations. It will be appreciated that the other pair of opposing anchors 44, 46 also have holes 60, 62 for another reinforcing bar. Additional holes may be provided adjacent to the holes 56, 58, 60, 62 to allow for another reinforcing bar parallel to the longitudinal line 54 if required. A transverse line 64 is also shown which represents the position of another reinforcing bar (not shown), through holes in the opposing side plates 14, 16 of the body 12. It will be appreciated that only one of these holes 66 is shown. Additional holes 67, 69, shown in
In
It will be appreciated that any suitable drive mechanism 78 could be used that provides the required movement of the barrier member 30 relative to the body 12. Suitable drive mechanisms may include a rack and pinion gear arrangement whereby the rack is mounted on the barrier member 30 and the pinion is one of the rollers 88, 90, 92.
In
Referring to
It will be further appreciated that to obtain at least a part of the benefit of the embodiments of the invention the distance 77 could be between 10%-95% of the radius 72, 74 of the barrier member 30 depending on the radius of curvature of the barrier member 30. In a preferred embodiment the distance shown at 77 is 65%-90% of the radius 72, 74 of the barrier member 30. In a further preferred embodiment the distance shown at 77 is 75% of the radius 72, 74 of the barrier member 30. Such a radius of curvature may be an average radius of curvature of the barrier member 30. It will be appreciated that the axis of rotation 76 of the barrier member 30 is in a fixed position relative to the barrier member 30 and the body 12 as the barrier member 30 is operated. In the embodiments shown the dimension 77 is about 830 mm, although it will be appreciated that the dimension 77 could be between 98 mm to 938 mm to gain at least a part of the benefit of the embodiment of the invention.
It will further be appreciated that the distance of the barrier member 30 in the stowed position below the top plate 22 is about 40% of the distance 105 of the barrier member 30 above the top plate 22 in the deployed position. Such an arrangement is provided by having the axis of rotation 76 above the top plate 22 at the distance 77 described above. It will be appreciated that varying the dimensions of the security barrier 10 might lead to the distance of the barrier member 30 in the stowed position below the top plate 22 relative to the distance 105 of the barrier member 30 above the top plate 22 in the deployed position being the range 25-55%.
The barrier member 30 has two internal plates 160, 162 which run along the length of the barrier member 30. The internal plates 160, 162 are welded to the first and second curved plates 132, 134 as shown at 153. At the end of the barrier member 30 having the shoulders 98 the barrier member 30 has two fingers 164, 166 which define a space 168 between them. The space 168 is for location of the actuator arm 84 so that it can be attached to the connection device 87. The internal plates 160, 162 also form the fingers 164, 166 and define the space 168.
In use, the actuator arm 84 has an eye which is located over the pin 182 of the second part 194. The pin 182 is then slidably engaged in the hole 181 of first support plate 180. The first and second connection plates 174, 186 of the first and second parts 192, 194 are then bolted together at 188 and 190. It will be appreciated that the first and second connection plates 174, 186 lie on top of each other. The connection device 87 is then located into the space 168 between the fingers 166, 168 so that the two holes 176, 178 of the first connection plate 174 align with the two holes 172, 174 of the connection member 146. The first connection plate 174 is then bolted to the connection member 146. Such an arrangement is advantageous because it allows the actuator arm 84 to be attached to the connection device 87 prior to locating it in the space 168 between the fingers 164, 166 which is small space. The connection device 87 simplifies the process of attaching the actuator arm 84 to the barrier member 30.
Whereas the barrier member 30 described above is about 380 mm in width, it is also envisaged that the bather member 30 might be substantially the width of a road, for example up to about 6 metres. In such an arrangement the body 12 may be required to be slightly wider than the barrier member 30 to accommodate it in the stowed position. Additional or more powerful actuators 82, 80 may also be required to operate the barrier member 30.
The barrier member 30 described above with reference to
In the above embodiments the security barrier 10 described is intended to be crash proof so that a car or lorry travelling at speed is substantially prevented from passing the barrier member 30. As such the security barrier 10 is relatively large and constructed of relatively heavy weight material. Such a security barrier 10 might alternatively be termed a high security barrier, a vehicle barricade, a truck stopper or a road blocker and might be particularly useful to guard against terrorist activities. It is also envisaged that a smaller version of the above described embodiments could be used for application at the home or business premises. Such a less heavy duty security barrier 10 may not require a drive mechanism and may be operated by hand. The less heavy duty security barrier 10 may be used to guard a parking space or driveway. The high security barrier 10 and the smaller version security barrier 10 may alternatively be termed a vehicle security barrier 10.
It will be understood that the barrier member 30 described above is arranged to be rotatably mounted relative to the body 12 so that it partially rotates. An alternative way of describing this arrangement is that the barrier member 30 is mounted to the body 12 so that it can pivot between the stowed position 110 and the deployed position 70 where the axis of pivoting 76 is above the top plate 22. It will be appreciated that the axes of pivoting 76 or the axis of rotating 76 is substantially parallel to the ground. This is in contrast to the prior art wedge-shaped or rectangular flat plate type security barriers which are pivotably connected at ground level to a support. With the present embodiments of the invention the barrier member 30 and the body 12 are connected to each other by the rollers 88, 90, 92 which act on a periphery of the barrier member 30 to provide the pivotable movement, or rotational movement of the barrier member 30 relative to the support. This is in contrast to the wedge-shaped or rectangular flat plate type security barriers of the prior art which are connected to a support located in the ground by a pivotable connection located at a thin end of the wedge or at one edge of the flat plate. With the above described embodiments it will also be appreciated that the bather member 30 is movable relative to the body 12 between a stowed position where at least a part of the barrier member 30 is below an upper part of the body 12, and a deployed position where at least a part of the barrier member 30 is above the upper part. The upper part may be the top plate 22 which is at ground level and which is a surface on which a vehicle can drive or a person can walk.
According to another way of describing the above embodiments the security barrier 30 may be considered to be a pendulum in that it has a pendulum mounting that permits the security barrier 30 to be moved between the stowed position 110 and the deployed position 70. The pendulum mounting is provided by the rollers 88, 90, 92 acting on the barrier member 30. As such the barrier member 30 and the body 12 to which the barrier member 30 is mounted may be considered to be a pendulum arrangement. In this pendulum arrangement the axis of rotation 76, which is above the top plate 22, is an axis of pivoting of the barrier member 30, or pendulum. In the stowed position 110 the bather member 30 is substantially at rest or substantially in the equilibrium position of the pendulum arrangement under the action of gravity. It will be appreciated that the force required to move the pendulum-like barrier member 30 away from the stowed position, or equilibrium position, increases as the barrier member 30 is moved towards the deployed position. This is due to the mass of the barrier member 30 which is distributed along the length of the barrier member 30. Such a requirement for an increasing force is in contrast to the prior art arrangements which typically require a constant force, or a decreasing force to deploy a barrier member to the deployed position. With the above embodiments, the mass of the barrier member 30 stays constant, but the weight of the barrier member 30 increases as it is moved away from the stowed position. This is due to the fact that the barrier member 30 is moved away from the equilibrium position.
Number | Date | Country | Kind |
---|---|---|---|
1006439.2 | Apr 2010 | GB | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/GB2011/000575 | 4/14/2011 | WO | 00 | 2/6/2013 |