EP1728926A1

EP1728926A1 - Vehicle blocking device

Info

Publication number: EP1728926A1
Application number: EP05253350A
Authority: EP
Inventors: Roger Phillip Knight
Original assignee: APT Controls Ltd
Current assignee: APT Controls Ltd
Priority date: 2005-06-01
Filing date: 2005-06-01
Publication date: 2006-12-06
Also published as: WO2006128857A1

Abstract

A blocking element (21) for use in a device for selectively allowing and preventing the passage of one or more vehicles along a pathway, the blocking element comprising: a framework supporting at least one frangible blocking face (23) facing the intended direction from which a collision might occur, the face and the frame forming a cavity (30) behind the face; and an engagement element (28) mounted in the cavity behind the blocking face, whereby, when the frangible blocking face is broken upon impact with a vehicle, the engagement element is revealed and is arranged to engage the tyres of the vehicle involved in the collision, thereby preventing the vehicle riding over the blocking element.

Description

This invention relates to a blocking element, typically for use in a device for selectively allowing and preventing passage of one or more vehicles along the pathway.
Various types of device for selectively allowing and preventing a passage of one or more vehicles along a pathway are known. In the simplest construction, one or more poles are pivotally connected to a surface such that they can be moved between a substantially horizontal position in which a passage is allowed along a pathway and a substantially vertical position into which they can be locked, thereby preventing passage along the pathway on which they are located. Such devices are extremely simple to manufacture and therefore relatively cheap, but do not provide a significant deterrent to a large or fast moving vehicle which is able to break the pole(s) and/or the locking means without difficulty. The pole(s) may or may not be housed in the substantially horizontal position within the pathway itself. However, the drawback that they are relatively unsubstantial and cannot withstand a vehicle colliding with them, in a determined effort to pass along a pathway which they block, means that they are not suitable for high security locations.
Other devices comprise one or more barrier elements which can be raised into position to prevent the passage along a pathway, many of which are hydraulically operated and are significantly more sturdy than the simple pole arrangement described above.
For example, it is well known to construct, typically from steel or other suitable strong material, a framework which is located substantially within the pathway, typically within a concrete casing within the ground. The framework supports, typically in a pivotal arrangement, a blocking element which can be raised from a first position in which its uppermost surface is substantially level with or below the surface of the ground and a second position in which at least a portion of the blocking element projects above the surface of the pathway to prevent passage along that pathway.
In order to present a significant barrier to vehicles and, in particular, to larger vehicles such as jeeps, lorries and coaches, such blocking elements typically project, in the second position, approximately one metre above the surface of the pathway which they are blocking.
In a collision between a vehicle and the blocking element, the majority of the force transmitted from the vehicle to the blocking element travels down the blocking element into the framework within the ground. However, if the wheels of the vehicle in the collision contact the face of the blocking element with which they collide, it is possible for the vehicle to ride up the blocking face such that the vehicle partially, or in the worse case example completely, passes over the blocking element and is able to continue travelling along the pathway. This is clearly an undesirable problem.
The present invention aims to provide a construction which reduces the likelihood of any vehicle being able to ride over the blocking element during a collision.
Whilst it would be possible simply to make the blocking element taller, such an increase in size significantly increases the cost and weight of the vehicle blocking device. In addition, any actuation means for moving the blocking element between the first and second positions must be significantly more powerful.
According to the present invention, there is provided a blocking element for use in a device for selectively allowing and preventing the passage of one or more vehicles along a pathway, the blocking element comprising:

a framework supporting at least one frangible blocking face facing the intended direction from which a collision might occur, the face and the frame forming a cavity behind the face; and
an engagement element mounted in the cavity behind the blocking face,
whereby, when the frangible blocking face is broken upon impact with a vehicle, the engagement element is revealed and is arranged to engage the tyres of the vehicle involved in the collision, thereby preventing the vehicle riding over the blocking element.

The engagement element may include a simple lip which engages with one or more wheels of the colliding vehicle. Preferably, however, the engagement element comprises at least one piercing portion for piercing tyres of the vehicle involved in the collision. The piercing portion is preferably a serrated edge, but could take other forms such as a series of separate prongs, spikes or the like, or even rounded points, cone shaped projections, a single knife edge or triangular points.
The breaking of the frangible blocking face preferably reveals a lip on the upper edge of the blocking element, the lip overhanging the remainder of the frame of the blocking element to assist in preventing a vehicle riding over the blocking element.
The frangible front face of the blocking element is preferably supported by one or more ribs which are sufficiently strong to support the frangible face of the blocking element against accidental collision with, for example, a person, but which are not sufficiently strong to withstand the impact with a moving vehicle.
The frangible front face preferably extends over substantially the whole of the front of the blocking element, but is supported at its upper end by a projection from the framework of the blocking element such that, when the frangible face is broken, the projecting portion of the frame forms the overhanging lip.
The blocking element is preferably located within a device for selectively allowing and preventing the passage of one or more vehicles along a pathway which further comprises a frame for, in use, insertion into the pathway and to which the blocking element is connected and is movable relative thereto, between a first position in which, in use, the blocking element allows passage along the pathway and a second position in which, in use, the blocking element projects from the frame so as to prevent passage along the pathway. The blocking element is preferably pivotally mounted on the frame.
It is also preferable that, in that particular arrangement, a latch element is provided on the blocking element for engaging with the frame when the blocking element is in the second position.
A plurality of latch elements may be provided at different positions on the blocking element. In particular, it is preferable that each latch element engages with the frame on the opposite of the frame to the connection of the frame and the blocking element. The provision of one or more latch elements between the blocking element and the frame ensures that a greater proportion of the strength of the frame can be utilised in absorbing an impact on the blocking element.
One example of the present invention will now be described with reference to the accompanying drawings, in which:

Fig. 1 is a view from the front, above and one side of a blocking device incorporating a blocking element according to the present invention;
Fig. 2 is a schematic side view showing the device of Fig. 1 in the raised position;
Fig. 3 shows a schematic view from the front, above and one side of a blocking element according to the present invention with the frangible face removed; and
Fig. 4 shows a side elevation view of the blocking element of Fig. 3.

Fig. 1 shows a device 10 for selectively allowing and preventing the passage of one or more vehicles along a pathway, the device comprising a framework 11 which, as can be seen from Fig. 2, is located within the ground 12 in use. The framework 11 comprises an upper 13 and a lower 14 support channel spaced apart by a plurality of substantially vertical props 15, typically in the form of an I-beam. A similar construction is used on the rear of the device and has upper 16 and lower 17 support channels spaced apart by props 15. Additional props 18, again in the form of I-beams, are provided between upper 19 and lower 19A side channels. Thus the frame 11 defines a substantially box like enclosure 20. A blocking element 21 is pivotally connected to the frame 11 at the upper rear channel 16. In Figs. 1 and 2, the blocking element 21 is shown in the raised position in which it projects above the level of the pathway 22. In Figs. 1 and 2, a blocking face 23 faces the intended direction of impact and takes the form of an arcuate surface. The blocking face 23 is frangible and is formed by a plurality of thin sheets of plastic, such as polypropylene, or other suitable material, e.g. perspex, thin metal sheet sheet or expanded foam which are fixed to the framework of the blocking element 21 as shown in Fig. 3.
As can be seen more clearly in Figs. 3 and 4, the blocking element 21 takes the form of a cylinder having a cross section which is a segment. The blocking element 21 is formed from a plurality of structural members 26a, 26b, 26c radiating from the apex of the segment and to which a further structural member 27 is connected, forming a substantially triangular shape when viewed from the side, as in Fig. 4. The structural member 27 is attached to the end of lower element 26c, but is connected to the upper element 26a at a short distance from its end, such that a lip 28 is formed. The blocking face 23 extends between the outermost portion of the lip 28 and the lower extreme of the lower member 26c. The frangible face 23 is supported by a plurality of ribs 29 which are themselves frangible such that, upon impact with a vehicle, the front face and the ribs are broken. The frangible face 23, the lip 28 and the opposing surface of structural element 27 form a cavity 30 within which a serrated edge 31 is retained. The serrated edge 31 is revealed when the frangible face and ribs are broken and is intended to engage with and pierce the tyres of any vehicle which collides with the blocking element, thereby preventing the vehicle riding over the blocking element. In addition, the lip 28 also hinders the vehicle in riding over the blocking element as it provides a further obstacle to easy travel of the vehicle.
The blocking element also incorporates a plurality of latch elements 24 which are fixed to the structural element 27 by means of four bolts 32. The latch elements 24 are substantially U-shaped having a latching portion 33 on the opposite arm of the U to the fixing bolts 32. The latching portion 33 of each latch element is intended to engage with the upper front channel section 13 of the framework when the blocking element 21 is in the second, raised position. By engaging with the upper front channel 13, any impact on the blocking element 21 is not only absorbed in the blocking element itself and by the pivotal connection between the blocking element 21 and the frame 11, but is also transmitted through the latching of the blocking element 21 to the upper front channel 13 of the frame. The impact is thus dissipated throughout the whole of the frame 11, thereby greatly enhancing the strength of the overall device.

Claims

A blocking element for use in a device for selectively allowing and preventing the passage of one or more vehicles along a pathway, the blocking element comprising:
a framework supporting at least one frangible blocking face facing the intended direction from which a collision might occur, the face and the frame forming a cavity behind the face; and

an engagement element mounted in the cavity behind the blocking face,

whereby, when the frangible blocking face is broken upon impact with a vehicle, the engagement element is revealed and is arranged to engage the tyres of the vehicle involved in the collision, thereby preventing the vehicle riding over the blocking element.
A blocking element according to claim 1, wherein the engagement element includes at least one piercing portion for piercing the tyres of the vehicle involved in the collision.
A blocking element according to either claim 1 or claim 2, wherein the framework includes a lip on an upper portion of the framework which is revealed upon breaking of the frangible blocking face.
A blocking element according to any one of claims 1 to 3, wherein the frangible face is supported on one or more ribs which extend from the framework.
A blocking element according to claim 4, wherein the supporting rib(s) is (are) frangible.
A blocking element according to any one of the preceding claims, further comprising a latch element for engaging, in use, with a supporting framework.
A blocking element according to claim 6, further comprising a plurality of latch elements.
A device for selectively allowing and preventing a passage of one or more vehicles along a pathway, the device comprising a frame for, in use, insertion into the pathway; and
a blocking element according to any one of the preceding claims connected to and movable relative to the frame between a first position in which, in use, the blocking element allows passage along the pathway and a second position in which, in use, the blocking element projects from the frame so as to prevent passage along the pathway.
A device according to claim 8 when dependent upon claim 6 or claim 7, wherein each latch element engages with the frame on the opposite side of the frame to the connection of the frame and the blocking element.
A device according to either claim 8 or claim 9, wherein the blocking element is pivotally connected to the frame.