GB2451065A

GB2451065A - Traffic flow control device

Info

Publication number: GB2451065A
Application number: GB0713721A
Authority: GB
Inventors: Graham Roger Richard Lee; Richard Michael Robert Lee
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-07-14
Filing date: 2007-07-14
Publication date: 2009-01-21
Anticipated expiration: 2027-07-14
Also published as: GB2451065A8; GB0713721D0; GB2451065B

Abstract

The traffic flow control device, primarily for use in car parks and the like, comprises a support body 41 and at least one barrier member 45 supported by and moveable relative to the support body between a first position in which it impedes the flow of traffic in a first direction and a second position to which it is moveable to permit a flow of traffic in a second, opposite direction, the device having magnetic biasing elements comprising two elements 47,49 associated respectively with the support body and barrier member and arranged to provide a biasing force to urge the barrier member to move from the second position to the first position and normally to be at rest in said first position. At least one of the elements may be a permanent magnet or an electro-magnet and/or one of the elements may be formed from a ferrous material. The device may comprise two magnets arranged to repel one another. The magnetic elements may be fully embedded in the support and barrier elements or located in dovetail-shaped recesses. The support body may be provided with a footprint sized to facilitate the use of adhesive to secure the device to the ground.

Description

1 2451065

TRAFFIC FLOW CONTROL DEVICE

This invention relates to a traffic flow control device and in particular, though not exclusively, to a traffic flow control device of the kind which allows vehicular traffic thereover in a first direction but inhibits vehicular traffic flow thereover in an opposite direction.

Traffic flow control devices of the aforementioned type typically are found in use in commercial car parks to allow vehicles freely to leave the car park by an authorised exit but inhibit vehicles using that exit as an entrance and thereby, for example, avoid paying an entrance fee.

As has been described in the specification of GB 2238565, it has for many years been the practice to provide a traffic flow control unit of a kind having a plate which is normally upstanding to act as a barrier to a vehicle wheel, but which is able to pivot in one angular direction under the weight of the vehicle wheel to permit the vehicle to pass in the authorised direction. Said known units comprise an extension arm associated with the barrier plate and located in a hollow container which, in use, typically is positioned below the level of the road surface. The need to excavate to accommodate the hollow container adds undesirably to the installation time and cost.

It is understood that the traffic flow control unit the subject of GB 2238565, and related GB 2270533, seeks to reduce the need for excavation by providing a torsion spring to maintain the barrier plate in a normally upstanding position as an alternative to relying on a counter-balance weight.

Whilst the use of a torsion spring enables the size of the hollow container to be reduced, there nevertheless remains the need to provide a housing to accommodate the torsion spring. Furthrmore, the torsion spring is prone to failure and to provide effective torsional force for example due to damage, corrosion or fatigue.

The present invention seeks to provide an improved traffic flow control device which enables the need for excavation to be avoided, and in which at least some of the aforedescribed difficulties of known devices are mitigated or overcome.

In accordance with the present invention there is provided a traffic flow control device comprising a support body and at least one barrier member supported by and moveable relative to the support body, said barrier member being moveable relative to the support body between a first, barrier position in which it impedes the flow of traffic thereover in a first direction of traffic flow and a second position to which it is moveable in response to, and to permit, a flow of traffic thereover in a second direction of traffic flow opposite said first direction of traffic flow, wherein the traffic flow control device comprises biasing means to urge the barrier member to move from the second position to the first position and normally to be at rest in said first position, said biasing means comprising magnetic biasing means comprising two elements associated respectively with the support body and barrier member and arranged to provide a biasing force to urge the barrier member to said first position.

At least one of the two elements of the magnetic biasing means may be a permanent magnet or an electro-magnet. Said magnet may be secured relative to one of the support body and barrier member and arranged to provide a biasing force which acts on another magnet or a ferrous element secured relative to or forming at least a part of the other of the support body and barrier member to tend to cause the two elements to move towards one another and urge the barrier member to said first position.

Each of the two elements may be a magnet and the two magnets may be arranged to repel one another thereby to provide a biasing force which urges the barrier member to said first position. It is further preferred that each of said two magnets is a permanent magnet but the invention envisages also that at least one or each of the two magnets may be an electro-magnet.

At least one of the two elements of the magnetic biasing means may be at least partially, and more preferably fully embedded in the material of one of the support body and barrier member. Said one or each of the support body and barrier member may be of a moulded plastics material, for example a composite material such as fibre filled plastics.

One or each of the support body and barrier member may be provided with a recess which is dovetail shaped in section, for example by moulding of material of the body or member so that a magnet of a complimentary shape may be slid into the recess in a direction which is substantially perpendicular to the direction in which the magnet exerts a biasing force in use of the traffic flow control device. Thus by virtue of that dovetail shape the magnet may be securely held in position relative to the support body or barrier member without the need for additional fixing means.

The barrier member and optionally also the support body may be moulded from a material of a colour, such as yellow or orange, which typically is recognised as performing a warning function.

As an alternative to having a magnet or ferrous element secured thereto or embedded therein, one of the support body and barrier member may be formed substantially wholly or comprise a substantial part which is of a ferrous material such as cast iron or mild steel.

Preferably the barrier member is moveable relative to the support body by a pivoting action. The support body may comprise a pair of pivot points relative to which the barrier member is secured and pivotably mounted for a limited degree of angular movement between said first and second positions.

The support body may have a substantially planar lower surface for mounting on a ground surface such as that provided by a layer of tarmac or concrete.

The support body may comprise retention formations, such as bolt apertures, to facilitate fixing of the traffic flow control device to a ground surface.

Alternatively, for example, the device may be secured to a ground surface by means of a suitable adhesive. Particularly if the traffic flow control device is to be secured with the use of an adhesive, the footprint of the support body may be larger than that necessary for providing support to the barrier member(s) such that the lower face of the support member is sufficiently large to provide an adequate bonded surface area for obtaining a sufficiently good strength of bond to the ground surface.

Although the support body may provide support for a single barrier member, it is to be understood that a single support body may provide support for a plurality of barrier members.

In hitherto known traffic flow control devices the barrier member is usually in the form of a substantially square plate of a width substantially equal to the typical width of a vehicle tyre, and the neighbouring plates are spaced by less than a typical minimum tyre width. Plates of such dimensions and spacings may be employed as the barrier member(s) of a traffic flow control device in accordance with the present invention.

However, the present invention further envisages that the support body may provide support for a plurality of pivotally mounted barrier members which are relatively narrow in the direction of the length of the pivot axis as compared with the length of the barrier member in a direction perpendicular to the pivot axis.

In hitherto known types of traffic flow control devices a mechanical stop is provided at a position below the surface of the road for the purpose of being engaged by a downward extension of the barrier plate to restrain the barrier plate against further rotation under the action of a counter-balance weight or torsional spring. In contrast, the present invention provides that mechanical stop means may be provided at a position above the ground surface, for example by rib-like formations of the support body provided also to define pivot positions.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings in which:-Figure 1 is a perspective view of a traffic flow control device in accordance with a first embodiment of the present invention; Figure 2 is an end view in the direction of the arrow X of Figure 1; Figure 3 is a side view in the direction the arrow Y of Figure 1; Figure 4 is a plan view of the device of Figure 1; Figure 5 is a sectional view of a traffic flow control device in accordance with a second embodiment of the present invention when in a first, raised position, and Figure 6 is a view corresponding to that of Figure 5, but showing the device when in a second, depressed condition.

A traffic flow control device 10 comprises a support body 11 and a plurality of barrier members in the shape of prongs 12 each pivotally mounted relative to the support body.

The support body and prongs are formed from moulded high density polyurethane.

The support body 11 is of a two-part construction comprising a flat base plate 13 and a plurality of spaced apart support ribs 14. The support ribs 14 are each secured to the base plate 13 by means of assembly dowels 15 to provide an integral construction. Spaces between the support ribs 14 which are not required to accommodate the prongs are occupied by filler strips 9 to provide a substantially smooth surface 8 which in use confronts on-coming traffic.

The base plate 13 is provided with apertures 16 for retention bolts 17 which enable the traffic flow control device to be secured to a ground surface.

The base plate 13 additionally has moulded therein a permanent magnet 18 at a position slightly off-set from the centre of the width of the base plate as viewed in Figure 2. The magnet 18 is oriented with one of the poles of the magnet facing upwards.

Each support rib 14 is of a shape substantially corresponding to that of an isosceles triangle and is provided with a pivot pin aperture 19 at a position which is central between the edges of the base plate as viewed in Figure 2, and spaced above the base plate 13.

In the final assembly of the traffic flow control device a pivot rod 20 extends through the aligned apertures of the plurality of support ribs 14.

At a position off-set from the centre of each rib, to a side opposite that at which the magnet 18 is off-set when viewed in Figure 2, each rib is provided with a second aperture 21. An abutment rod 22 extends through the aligned second apertures 21 of the plurality of support ribs 14.

The pivot rod 20 provides a pivotal support for each of the barrier prongs 12 which are positioned one each between each successive pair of support ribs.

Each barrier prong is of a substantially triangular shape and tapers from a base end 23 to a distal end 24. The base end is provided with an aperture 27 through which the pivot rod 20 extends.

The base end 23 additionally comprises a pair of abutment surfaces 25, 26.

One abutment surface 25 abuts the abutment rod 22 when the barrier prong is at rest in a first, raised position as shown in Figure 2. The other abutment surface 26 abuts the abutment rod 22 when the barrier prong is in a second, depressed position when vehicular traffic is flowing thereover. Additionally, in the second, depressed position a side face 29 of each barrier prong rests upon the upper surface 30 of the base plate 13.

Each barrier prong has moulded therein a permanent magnet 28 at a position near the base end 23. The magnet 28 is positioned such that when the barrier prong is in a depressed position that pole of the magnet which is of the same polarity as that of the upward facing pole of the base plate magnet 18 confronts said magnet 18. Accordingly, in the absence of a flow of traffic which depresses the barrier prong, each barrier prong is urged to the first, raised position in consequence of the inherent tendency of the like poles of the magnets 18, 28 to repel one another.

In the illustrated embodiment of Figures 1 to 4, when the barrier prong 12 is in a depressed position the confronting surfaces of the magnets are substantially parallel. However, the magnet 28 may be provided in other positions. For example it may be rotated to lie in a position slightly clockwise from that shown in Figure 2 such that when the barrier prong is depressed, the confronting surface of the magnet 28 is inclined relative to the base plate surface 13. Thus the maximum repulsion force arises which the barrier prong is slightly above the base plate, and in consequence the repulsion force when the barrier prong is in the first, raised position, will be slightly greater than in the illustrated configuration in which the confronting magnet surfaces are parallel when the barrier prong is at the second position.

In a second embodiment of the present invention, illustrated in Figures 5 and 6, a traffic flow control device has substantial similarities with that described in relation to the traffic flow control device of Figures 1 to 4, but with the differences discussed below.

The traffic flow control device 40 comprises a support body 41 having a base plate 42 of cast iron or other ferrous material and a plurality of moulded plastics support ribs 42 secured thereto and corresponding substantially with the aforedescribed support ribs 14.

A support rod 44 extends through aligned apertures of the plurality of support ribs 43 and provides pivotal support for the barrier prongs 45.

Spaces between the support ribs 43 are occupied by filler strips 48 of moulded plastics material and of a shape substantially similar to that of the aforedescribed filler strips 9. The filler strips 48 are firmly secured to the base plate 42 and each have a permanent magnet 47 embedded therein at an end region 46 which lies close to but (as viewed in Figure 5) slightly off-set transversely from the pivot rod 44.

Each barrier prong 45 is formed from moulded plastics material and has a permanent magnet 49 embedded therein at a position transversely off-set from the pivot rod 44 to that side of the pivot rod 44 opposite the distal end 40 of the barrier prong.

The positioning of the magnets 47, 49 is arranged such that when the barrier prong 45 lies in a second, depressed position as shown in Figure 6, the confronting surfaces of the magnets which are exposed relative to the plastics material in which they are embedded lie substantially aligned and have like poles confronting each other. In consequence the magnets 47,49 will tend inherently to cause the barrier prong 45 to rotate in an anti-clockwise direction as viewed in Figures 5 and 6 to a first, raised position under the action of the repulsion force created by the like poles of the magnets. That force is further assisted by the inherent tendency of the barrier prong magnet 49 to be attracted to the ferrous material of the base plate 42.

Although the clockwise movement of the barrier prong 45 about the pivot rod 44 may be arrested by the magnet 49 and adjacent material of the barrier prong contacting the region 46 of a filler strip 48, in this embodiment the spaces between successive support ribs 43 are each occupied by a stop member 51 which is contacted by the distal end region 50 of the barrier prong when that prong is in the second, depressed position.

Although the invention has been described particularly with reference to barrier members in the form of prongs having a greater length than width, it is to be understood that barrier members of a more conventional shape, for example having a width substantially equal to their length, may be employed.

Furthermore, although the first example of the invention as described above utilised the repulsion force bewteen like poles of two magnets and the second embodiment utilises that force in combination with the force of attraction between a permanent magnet and ferrous material, it is to be understood that other configurations are possible including for example one in which only forces of attraction are utilised. ECDE3

Claims

Claims 1. A traffic flow control device comprising a support body and at least one barrier member supported by and moveable relative to the support body, said barrier member being moveable relative to the support body between a first, barrier position in which it impedes the flow of traffic thereover in a first direction of traffic flow and a second position to which it is moveable in response to, and to permit, a flow of traffic thereover in a second direction of traffic flow opposite said first direction of traffic flow, wherein the traffic flow control device comprises biasing means to urge the barrier member to move from the second position to the first position and normally to be at rest in said first position, said biasing means comprising magnetic biasing means comprising two elements associated respectively with the support body and barrier member and arranged to provide a biasing force to urge the barrier member to said first position.
2. A traffic flow control device according to claim 1 wherein at least one of the two elements of the magnetic biasing means is a permanent magnet.
3. A traffic flow control device according to claim 1 wherein at least one of the two elements of the magnetic biasing means is an electro-magnet. *...
4. A traffic flow control device according to any one of the preceding claims wherein the magnetic biasing means comprises a magnet secured relative to one of the support body and barrier member and arranged to provide a biasing force which acts on another magnet. S...

*:*.
5. A traffic flow control device according to any one of the preceding claims wherein the magnetic biasing means comprises a magnet secured relative to one of the support body and barrier member and arranged to provide a biasing force which acts on a ferrous element secured relative to or forming at least a part of the other of the support body and barrier member.
6. A traffic flow control device according to any one of claims 1 to 3 wherein each of the two elements of the magnetic biasing means is a magnet and the two magnets are arranged to repel one another thereby to provide said biasing force which urges the barrier member to said first position.
7. A traffic flow control device according to any one of the preceding claims wherein at least one of the two elements of the magnetic biasing means is partially embedded in the material of one of the support body and barrier member.
8. A traffic flow control device according to any one of claims 1 to 6 wherein at least one of the two elements of the magnetic biasing means is fully embedded in the material of one of the support body and barrier member.
9. A traffic flow control device according to any one of the preceding claims and comprising a support body and or barrier member of moulded plastics material.
10. A traffic flow control device according to any one of the preceding claims wherein at least the barrier member is moulded from a material of a colour selected to perform a warning function. S. * S
11. A traffic flow control device according to any one of the preceding S..).

claims wherein one or each of the support body and barrier member is S.,..' provided with a recess of a dovetail shape in section whereby a magnet of a complimentary shape may be slid into the recess in a direction which is substantially perpendicular to the direction in which the magnet exerts a 5..

biasing force.
12. A traffic flow control device according to any one of the preceding claims wherein the barrier member is moveable relative to the support body by a pivoting action.
13. A traffic flow control device according to claim 12 wherein the support body comprises a pair of pivot points relative to which the barrier member is secured and pivotally mounted for a limited degree of angular movement between said first and second positions.
14. A traffic flow control device according to any one of the preceding claims wherein the support body comprises a substantially planar lower surface for mounting on a ground surface.
15. A traffic flow control device according to any one of the preceding claims wherein the support body comprises retention formations to facilitate fixing of the traffic flow control device to a ground surface.
16. A traffic flow control device according to any one of the preceding claims wherein the footprint of the support body is greater than that necessary for providing support to the barrier member(s) and presents an adequate surface area for adhesive bonding of the support body to a ground surface.
17. A traffic flow control device according to any one of the preceding claims wherein the support body provides support for a plurality of barrier members. * * *4. S
18. A traffic flow control device according to any one of the preceding claims wherein the support body provides support for a plurality of pivotally mounted barrier members which are each relatively narrow in direction of the length of the pivot axis as compared with their length in a direction perpendicular to the pivot axis.
19. A traffic flow control device according to claim 1 and substantially as hereinbefore described.
20. A traffic flow control installation comprising a traffic flow control device according to any one of the preceding claims secured to a ground surface.
21. A traffic flow control installation according to claim 20 wherein the support body is secured to a ground surface by the use of an adhesive.
22. A traffic flow control installation according to claim 21 wherein the support body has a footprint larger than that necessary for providing support to the barrier member(s), the lower face of the support body being sufficiently large to provide a surface area sufficient for obtaining a good strength of bond to the ground surface.
23. A traffic flow control installation according to any one of claims 20 to 22 and comprising mechanical stop means to limit rotation of the barrier member from the second position to the first position under the action of the biasing means, said mechanical stop means being provided at a position above the ground surface.
24. A traffic flow control installation according to claim 23 wherein the support body comprises rib like formations to act as said mechanical stop means and also define pivot positions. I. * S * *.*
25. A traffic flow control installation according to claim 20 and subatanially as hereinbefore described. * S. *5 5 * SS 5.55 a *..* ** S S 55 * S. ECCL1