GB2086967A

GB2086967A - Road surface hump

Info

Publication number: GB2086967A
Application number: GB8035832A
Authority: GB
Original assignee: HAZARD WARNING SYSTEMS Ltd
Current assignee: HAZARD WARNING SYSTEMS Ltd
Priority date: 1980-11-07
Filing date: 1980-11-07
Publication date: 1982-05-19

Abstract

A preformed rubber speed ramp which is fixed to a road surface to provide a low obstacle over which vehicles may pass and thereby receive a shock comprises two substantially flat inclined surfaces (12 and 13) which are of substantially different length and inclination, so that a different effect is felt by a vehicle driver depending on the direction of travel of the vehicle over the ramp. <IMAGE>

Description

SPECIFICATION Speed ramp Description of Invention This invention relates to a speed ramp.

Speed ramps are used to alert vehicle drivers who have driven into a danger zone and also to encourage drivers to obey speed limits, particularly low speed limits of the order of 5 m.p.h. A shock is communicated through a vehicle which passes over a speed ramp, the severity of the shock being dependent, among other factors, on the vehicle's speed, the distance between margins of the ramp which are spaced apart in the direction of traffic flow (called hereinafter primary margins), and the height of the ramp. The height is that distance measured at right angles to a base plane extending between the primary margins, which extend from the base plane, to the part of the ramp which is spaced furthest from the base plane, that is the top of the ramp.

According to one aspect of the invention, there is provided a speed ramp wherein the distance from one of the primary margins to the top of the ramp substantially exceeds the distance from the other primary margin to the top of the ramp.

The shock which is imparted to a vehicle passing over a ramp according to the invention is different depending on which primary margin of the ramp is presented to an ancoming vehicle. A choice may be made in the orientation of the ramp, and thereby in the effectiveness with respect to vehicle travel in a particular direction.

An example of a ramp in accordance with the invention will now be described, with reference to the accompanying drawing wherein: FIGURE lisa cross-section of the ramp; and FIGURE 2 is a perspective view of the ramp.

Figure 1 shows a cross-section of a ramp 10 on a road surface 11. Two upwardly facing surfaces 12 and 13 intersect at the top 14 of the ramp.

Since the surfaces are substantially flat, the top is a well defined line and is clearly visible to an observer. The top is the furthest part of the ramp from a flat base 1 5 which is in face-to-face contact with the road surface. In another example of a ramp other than the one illustrated, where the surfaces 12 and 1 3 do not intersect along a line, the top may be a third upwardly facing surface.

The cross-section of the ramp 10 would be substantially triangular but for the truncations at two of the apices of the triangle. These truncations form margins 16 and 17 of the ramp. Each of the margins is a surface, which surfaces are substantially vertical and comprise those parts of the ramp which are spaced furthest apart in a cross-section as shown in Figure 1, Surfaces 23 and 24, which are adjacent to the margins 1 6 and 1 7 respectively, define equal angles with the base 1 5. Accordingly clamps 18, which bear on said surfaces may be used interchangeably. Bolts 1 9 secure the clamps to the road surface 11 so that the ramp is held between the clamps and the road surface.Once the clamps are positioned so that they bear on the surfaces 23 and 24, no alignment by movement in a direction transverse to the cross-section is necessary.

The height of the ramp, measured from base to top, preferably lies within the range 6 centimetres to 10 centimetres. In the particular example illustrated the dimension is between 7 and 8 centimetres high. The distance between the margins 1 6 and 1 7 is preferably less than five times the distance from the base to the top of the ramp; in the example illustrated the distance from one margin to the other lies between 1 9 and 20 centimetres.

The distance measured from margin 1 7 to the top 14 of the ramp is preferably greater than one and one half times the distance from the other margin to the top and, in the example illustrated, is approximately twice as great. Surface 13 defines an angle with the base 1 5 which may be greater than 300, is preferably greater than 350, and in the example illustrated is approximately 380. The angle which surface 12 defines with base may be less than 25 , is preferably less than 200, and in the example illustrated is approximately 170.

In use, vehicles driving along the road surface 11 may pass over the ramp 10, the vehicle wheels rolling over margins 16 and 17 and the surfaces 12 and 13. The ramp imparts a greater shock to vehicles with wheels which ascend the long surface 13, as they pass over the top 15, than to vehicles with wheels which pass over the top after ascending the short surface 1 2. (The surface 12, however, presents a more imposing view of the ramp to approaching drivers.) The ramp may easily be turned around or moved after removing the bolts 19.

Figure 2 shows a perspective view of the ramp with clamps in place. The ramp and clamps are elongated, extending in a direction transverse to the direction of traffic flow when the ramp is on the road surface 1 The ramp is formed of rubber which is extruded along its length by which process the surfaces 12, 13 and 1 5 of the ramp are formed with no substantial irregularities. A cross-section of the ramp at any point along its length is substantially the same as the crosssection shown in Figure 1. The upwardly facing surfaces 12 and 13 may be painted or dyed in order to make the ramp more distinctive. The ramps may be of various lengths.

A series of ramps may extend across the width of a road, with ends 22 of ramps engaged in faceto-face contact with each other. Primary margin 17, say, of adjacent ramps in a series may face in opposite directions so that different shocks may be imparted, for example, to vehicles travelling in different lanes on a road.

As well as or instead of the clamps 1 8 a ramp 10 may be held in position on a road surface 11 by a cable 20. Figure 2 shows the cable as a loop which extends through two holes 21 and emerges from each end 22 of the ramp. The cable may be engaged with some stable object where it emerges from the ends of the ramp or the exposed ends of a series of ramps.

Claims

1. A speed ramp wherein the distance from one of the primary margins to the top of the ramp substantially exceeds the distance from the other primary margin to the top of the ramp.

2. A speed ramp according to claim 1 wherein the distance from one of the primary margins to the top of the ramp is greater than one and one half times the distance from the other of the primary margins to the top.

3. A speed ramp according to either preceding claim wherein a respective flat continuous surfaces of the ramp extends from the top at least a part of the way towards each margin.

4. A speed ramp according to claim 3 wherein one of said surfaces defines a first angle with the base plane which is greater than 300 and the other surface defines a second angle which is less than 250.

5. A speed ramp according to claim 4 wherein said first and second angles are respectively greater than 350 and less than 190.

6. A speed ramp according to any preceding claim wherein the distance from one primary margin to the other is less than five times the distance from the base to the top of the ramp.

7. A speed ramp according to any preceding claim wherein the distance from the base to the top of the ramp is greater than 6 centimetres and is less than 10 centimetres.

8. A speed ramp according to any preceding claim wherein the ramp is truncated at one or both of the primary margins.

9. In combination with a speed ramp as hereinbefore described, a plurality of clamps which hold the ramps when in use, on a road surface which clamps bear on the ramp adjacent to respective ones of the primary margins of the ramp, and are engaged with the road surface.

10. A speed ramp according to any preceding claim wherein a length of cable extends through the ramp and is anchored externally of the ramp.

1 A speed ramp according to claim 10 wherein the cable is a loop which extends through two apertures in the ramp.

12. A speed ramp according to any preceding claim wherein the ramp is elongated and is formed of rubber which is extruded along the length of the ramp.

13. A speed ramp substantially as herein described, with reference to and as shown in the accompanying drawing.

14. Any novel feature or novel combination of features disclosed in the accompanying description and/or drawing.