[0001] This invention relates to a reflective road stud and more particularly to a reflective
road stud which is resistant to impact by a snow plough.
[0002] Snow ploughs in some countries are set to traverse a path slightly above the road
surface so as to prevent damage to the road surface and to reflective road studs set
in the road surface. In other countries, the plough is set to make contact with the
road surface with the result that reflective road studs set in the road surface are
damaged or destroyed.
[0003] The present invention seeks to provide a reflective road stud which is resistant
to impact by a snow plough.
[0004] According to the present invention there is provided a reflective road stud comprising
a hollow plastics body, a reflector support integral with the body and projecting
above the body, and a reflector supported by the reflector support, the support being
deformable into the body upon receiving an impact from either of two opposite sides
of the road stud.
[0005] Preferably, the road stud also comprises wiper means for cleaning the reflector when
the reflector support is deformed into the body.
[0006] Preferably, the reflector support lies proud of the hollow plastics body and includes
two ramp surfaces on each of said two opposite sides of the road stud, which, when
impacted, result in the reflector support being deformed into the body. In this case,
the reflector support also comprises a bar extending between the two ramp surfaces
on each of said two opposite sides of the road stud and a reflector on at least one
and preferably on each side of the bar. Also, in this case, the wiper means, when
provided, may be in the form of two blades integral with the body and extending inwards
from opposite sides of the body towards the bar.
[0007] Advantageously, the hollow body contains a closed cell foam material, a blow moulding
or solid elastomeric material to prevent ice build up in the body which may otherwise
resist or prevent deformation of the reflector support into the body.
[0008] Preferably, the body and support are formed of flexible, impact and abrasion resistant,
plastics material.
[0009] Preferably, the road stud also comprises a housing for receiving and locating the
hollow plastics body.
[0010] The invention will now be more particularly described by way of example with reference
to the accompanying drawings, in which:-
Figure 1 is a perspective view of one embodiment of a road stud according to the invention,
Figure 2 is a perspective view of the road stud with the outer housing omitted,
Figure 3 is a side view of the road stud with the outer housing omitted,
Figure 4 is a front view of the road stud with the outer housing omitted,
Figure 5 is an underneath perspective view of the road stud with the outer housing
omitted, and
Figure 6 is a perspective view of the outer housing.
[0011] Referring now to the drawings, the reflective road stud shown therein comprises an
outer plastics housing 10 and a hollow plastics body 11 located in the housing 10.
[0012] The housing 10 has a base and a generally rectangular wall with curved corner sections
defining a cavity for receiving the body 11. The housing has a flange 12 at is upper
end, six outwardly extending projections 13, external ribs 14 and four internal lugs
15. The housing 10 is located in a hole in the road surface and grouted in place.
The dimensions of the hole are selected such that the lower projections 13 are deformed
upwardly by engagement with the walls of the hole as the housing is placed in the
hole to prevent the housing from floating when a grouting mixture is poured into the
hole. The upper projections 13 contact the road surface to support the housing at
the correct level while the housing is grouted in place. The ribs 14 help to key the
housing to the grouting mixture and the internal lugs 15 co-operate with the body
11 in a manner to be described hereinafter.
[0013] The plastics body 11 has two side walls 16 and two end walls 17 joined by curved
corner sections 18 and is open at the bottom. A reflector support 19 is provided at
the top of the body 11 and is integral therewith.
[0014] The reflector support 19 comprises two ramp surfaces 20 on each side of the body
11 and at opposite ends, respectively, of the body 11. The ramp surfaces 20 are defined
by arms 21 which are inclined upwards from respective side walls 16 and which are
joined in the centre by a bar 22 extending between the ends of the body 11.
[0015] A reflector 23, which may be formed of biconvex lenses or which may be a cube-corner-type
retrodirective reflector or prismatic, is secured to each of the two longitudinally
extending sides of the bar 22.
[0016] The body 11 and reflector support 19 are formed of flexible, abrasion and impact
resistant, plastics material such as that made and sold by Hoechst Polymers under
the name Riteflex (TM) and the reflector support 19 is such that it will deform into
the body 11 upon receiving an impact from either of two opposite sides of the road
stud or from above. The housing 10 may be formed of the same plastics material.
[0017] The road stud also comprises two wiper blades 24 which are integral with the body
11 and which extend inwards from respective side walls 16 at positions immediately
below elongate recesses 25 formed in the upper edges of the two side walls 16, respectively.
The blades 24 extend as far as the bar 22 and wipe the surfaces of the reflectors
23 each time the reflector support 19 is deformed into the body 11 to clean the reflectors
23. A recess 26 is formed in each side wall 16 immediately below the wiper blades
24 for snap fittably receiving the internal lugs 15 of the housing 10. The blades
overhang the outer surface of the side walls 16 by a short distance and co-operate
with the wall of the housing 10 to keep the wiper blades 24 in contact with the reflectors
23 when the reflector support 19 is deformed into the body 11. Slits 27 are provided
in the side walls 16 at opposite ends of the wiper blades 24 to allow the reflector
support 19 to be deformed into the body 11 without deforming the wiper blades 24.
[0018] The body 11 is located as a snap fit in the housing 10 with the upper edge of the
body 10 flush with or slightly below the upper surface of the housing 10 and with
the reflector support 19 lying proud of the upper surface of the housing 10.
[0019] The body 11 is substantially filled with closed cell foam material 28 which may be
recessed in its upper surface to receive the bar 22 and reflectors 23 when the reflector
support 19 is deformed into the body 11. This foam material is impervious to water
and therefore prevents ice build up which could otherwise resist or prevent deformation
of the reflector support 19 into the body 11. A blow moulding or solid elastomeric
material could be used instead of the foam material.
[0020] In use, the reflector support 19 will deform into the body 11 when impacted by a
snow plough to prevent damage to the road stud. The reflector support 19 will also
be deformed into the body 11 when a vehicle wheel passes over the road stud and contact
between the wiper blades 24 and the reflectors 23 when this happens will ensure that
the reflectors 23 are kept reasonably clean. The foam material may also assist in
cleaning the reflectors 23 when the reflector support 19 is deformed into the body
11.
[0021] The embodiment described above is given by way of example only and various modifications
will be apparent to persons skilled in the art without departing from the scope of
the invention. For example, the ramp surfaces 20 could be arcuate rather than flat.
Also, the housing 10 could be omitted and the body 11 could be set in a hole in the
road by adhesive.
1. A reflective road stud comprising a hollow plastics body (11), a reflector support
(19) integral with the body and projecting above the body, and a reflector (23) supported
by the reflector support, the support being deformable into the body upon receiving
an impact from either of two opposite sides of the road stud.
2. A reflective road stud as claimed in claim 1, further comprising means (24) for cleaning
the reflector when the reflector support is deformed into the body.
3. A reflective road stud as claimed in claim 1 or claim 2, wherein the reflector support
lies proud of the hollow plastics body and includes two ramp surfaces (20) on each
of said two opposite sides of the road stud, which, when impacted, result in the reflector
support being deformed into the body.
4. A reflective road stud as claimed in claim 3, wherein the reflector support also comprises
a bar (22) extending between the two ramp surfaces (20) on each of said two opposite
sides of the road stud and a reflector (23) on at least one side of the bar.
5. A reflective road stud as claimed in claim 3 or claim 4 when dependent on claim 2,
wherein the wiper means is in the form of two blades (24) integral with the body and
extending inwards from opposite sides of the body towards the bar.
6. A reflective road stud as claimed in any one of the preceding claims, wherein the
hollow body contains a closed cell foam material (28), a blow moulding or solid elastomeric
material to prevent ice build up in the body which may otherwise resist or prevent
deformation of the reflector support into the body.
7. A reflective road stud as claimed in any one of the preceding claims, wherein the
body and support are formed of flexible, impact and abrasion resistant, plastics material.
8. A reflective road stud as claimed in any one of the preceding claims, further comprising
a housing (10) for receiving and locating the hollow plastics body.
9. A reflective road stud as claimed in claim 8, wherein the hollow plastics body is
a snap fit in the housing.
10. A reflective road stud as claimed in claim 8 or claim 9, wherein the housing is also
formed of plastics material.