Field of the Invention
[0001] The present invention concerns a guard for a safety barrier which is adapted to provide
added protection for workmen who are working alongside the safety barrier. The guard
applies primarily to temporary/ mobile barriers for road construction and maintenance
works but may also be useful for other similar situations where workers need to work
alongside a safety barrier in proximity to fast-moving vehicles.
Background to the Invention
[0002] During road construction and maintenance works it is customary to separate the lane
in which the work-men are operating, e.g. hard shoulder, from the nearest open traffic
lane by a safety barrier. The primary current model of safety barrier for road traffic
in universal use throughout the UK is a robust steel mobile safety barrier known as
the VARIOGUARD
(R) as manufactured by Asset International.
[0003] Referring to Figure 1, this commonest mobile safety barrier comprises modular barrier
lengths 1 of the order of 4m long and each ground-standing to be of the order of 0.9m
high to deflect road vehicles. Each barrier length 1 has a broad support base 2 that
is 0.7m wide at the ground and tapering inwardly upwardly to grip and hold upright
a number of posts or legs 3 at spaced intervals along its length. The tops of the
posts 3 bear a horizontal box beam 4 that is fixed to the post tops. The system is
designed to be installed rapidly in the 4m lengths with the lengths linked together
end-to-end. The assembled chain of barrier lengths 1 primarily relies on its weight
to hold it in place, being anchored only at conveniently spaced apart terminal locations,
which are commonly hundreds of metres apart. The safety barriers of this type are
extremely quick to install in long lengths and generally do their job well but they
can present a particular hazard when struck by vehicles in that they can in some circumstances
transmit an impact wave along the chain of the safety barrier that can cause it to
whip farther down the chain. This can be dangerous to work-men that are too close
to the barrier when whipping occurs. For most practical purposes it is necessary for
the work-men to stay a minimum distance of between about 0.9m and 1.03m away from
the safety barrier at all times in case such impacts arise but they will often stray
over th is limit.
[0004] It is an objective of the present invention to provide a guard for a safety barrier
of the type in question and which seeks to mitigate or prevent such hazard by ensuring
the workmen keep their distance from the barrier.
Summary of the Invention
[0005] According to a first aspect of the present invention there is provided a guard for
an elongate safety barrier to provide added protection for workmen who are working
alongside the safety barrier, the guard comprising a mounting bracket to mount onto
a safety barrier and that holds in use an arm whereby the arm projects transversely
from the barrier so that its distal end remote from the barrier is a predetermined
distance from the axis of the barrier to define a safe operational distance from the
safety barrier for workmen.
[0006] Particularly usefully, the mounting bracket has a resilient clip structure for quick
assembly to a safety barrier. This greatly enhances speed and economy of installation
and especially where the barrier is already in place and the guards are fitted to
the barrier in situ. For the commonest type of mobile safety barrier described above
the mounting bracket has a form that is shaped to embrace the box beam at the top
of the barrier. It preferably has an open collar-like form with a limb or pair of
limbs that reaches around the barrier's beam. The limb or limbs resiliently flex open
like jaws to fit around the barrier's beam.
[0007] In the preferred form the mounting bracket has a pair of opposing limbs that fit
over the respective opposing sidewalls of the box beam and with inward returning lips.
The lips face the underside, if mounted from above, or topside, if mounted from below,
of the box beam to secure the mounting bracket to the barrier.
[0008] For extra security of hold of the mounting bracket to the barrier when installed,
the bracket may be provided with a clasp or other releasable fastening means on the
limb or limbs to releasably fasten the limb or limbs in place, closed around the barrier.
[0009] The mounting bracket is preferably moulded of plastics or may be of a light spring
steel to provide the resilient clipping function. It does not need to be strong since
it does not need to have a barrier function. The purpose of the guard is to deter
workmen from straying too close to the safety barrier. It is suitably clipped onto
the beam of the barrier at intervals along the length of the barrier, for example
at intervals of the order of every 5m along the barrier.
[0010] The arm may be marked or coloured for high visibility, ie with yellow or red or other
colours that contrast strongly to the grey of the steel barrier and may suitably have
luminous coloration and or striped hazard warning markings thereon_ It may be provided
as a set of coloured arms that provide a countdown marker to alert to the proximity
of the entrance to/ exit from the workmen's area.
[0011] The distal end of the arm away from the barrier preferably is adapted to receive
a rope, cord, tape or other elongate line that may be strung therefrom parallel to
the length of the barrier. In preferred embodiments the distal end of the arm has
apertures for the line to pass through or, better still for speed of installation,
one or more notches on an edge through which the line may pass.
[0012] Importantly the arm is flexible to be able to flex if struck by a vehicle so that
it does not represent a hazard itself. Suitably it is of a plastics material - preferably
an extrusion of a plastics, e.g. such as of nylon or polyethylene, and preferably
has the form of a slim bar. In one embodiment it resembles a thick plastics metre
ruler in its form and dimensions. Under extreme impact the arm will suitably snap
off.
[0013] The mounting bracket preferably is configured to de-mountably hold the arm so that
the arm may be replaced if it is damaged and allowing for stowage of the arm alongside
the barrier lengths in storage or transport. The bracket suitably has a socket into
which a proximal end of the arm mounts and which suitably has one or more releasable
clamping means such as for example a threaded bolt that engages and releasably secures
the arm in the socket. In practice it is preferred to pre-assemble the arms to the
mounting brackets off-site to allow for speedy installation.
[0014] In other embodiments of the invention the mounting bracket/ mount for the arm may
be formed or assembled integrally to the safety barrier so that the guard becomes
an in-built feature of the safety barrier requiring only the addition of the arm on-site.
The mount in that case may comprise a simple socket on a side of the box beam of the
barrier and preferably having a fastening means to secure the arm in the socket in
use.
Brief Description of the Drawings
[0015] A preferred embodiment of the present invention will now be further described, by
way of example only, with reference to the accompanying drawings, in which:
Figure 1 is a vertical section view of a typical VARIOGUARD(R) road traffic safety barrier to protect workmen, showing the base, upstanding support
post and box-section horizontal beam of the barrier,
Figure 2 is a side elevation view of the guard of the preferred embodiment of the present
invention, showing the mounting bracket that fits onto the box beam of the barrier
and the arm extending from the bracket;
Figure 3 is a plan view of the guard of Figure 2 from above;
Figure 4 is an end elevation view of the guard;
Figure 5 is a side elevation view of a variant of the bracket incorporating a securing clip;
and
Figure 6 is an end elevation view of the Figure 5 bracket.
Description of the Preferred Embodiment
[0016] Referring to Figure 1. the typical VARIOGUARD
(R) road traffic safety barrier to protect workmen comprises a base 2, upstanding support
post 3 and box-section horizontal beam 4 that extends in the lengthwise direction/
axis of the barrier 1 as noted previously.
[0017] The guard 5 of the preferred embodiment of the present invention comprises a mounting
bracket 6 that is adapted to quickly and securely fit onto the box beam 4 of the barrier
1. The guard 5 also comprises an arm 7 extending a predetermined distance from the
mounting bracket 6 orthogonal to the bracket 6 such that it is substantially horizontal
and orthogonal to the lengthwise direction/axis of the barrier 1 and provides the
required safe clearance from the barrier 1. The extent of projection of the arm 7
corresponds to the allowed speed of traffic in the adjacent open traffic lane. This
is suitably of the order of 600mm for slow-moving 50mph restricted traffic or greater
for higher traffic speed limits e.g. of the order of 900mm at about 60mph or of the
order of 1030mm for speed of traffic up to 70mph. Indeed the arm 7 may be fitted to
the mounting bracket 6 in a way that allows adjustment of the length of projection
of the arm 7. preferably in discrete steps to suit the allowed speed of traffic.
[0018] The mounting bracket 6 is moulded of plastics or formed of a light spring steel and
defines a resilient clip structure 6a. It has limbs configured to embrace the box
beam 4 at the top of the barrier 1 and through resilient flexure apart of the limbs
like an opening jaw it may be put into place on the beam 4 at any point along the
length of the beam 4 and the limbs resiliently close together to fit or grip around
the beam 4. The clip structure 6a has a collar-like form with an opposing pair of
limbs 6b that extend over the respective opposite sidewalls of the box beam 4. The
lower ends of limbs 6b have inward returning lips 6c that extend towards each other
and face against the underside or topside of the box beam 4 to clippingly detain and
secure the mounting bracket 6 to the barrier 1. The mounting bracket 6 may be fitted
to the box beam 4 from above or from below and In the letter case will fall vertically
more readily when disengaged from the box beam 4.
[0019] In a variant of the mounting bracket shown in Figures 5 and 6, the bracket may have
the limbs 6b configured to be fastened secure together once they have snapped resiliently
close in together around the box beam 4. Here the bracket is slimmer and one or both
of the returning lips 6c are longer to meet closer together and be secured/ latched
close together by a latching clip or clasp 10. The latching clip or clasp 10 shown
is of quick-release type, having a pivoting loop 10a of the clasp 10 on one lip 6c
that engages with a hook 10b of the clasp 10 on the other lip 6c.
[0020] The mounting bracket 6 may be further adapted to have a socket or auxiliary bracket
6d as mounting means to hold a countdown marker flag to the barrier to highlight proximity
to the exit / entry points through the barrier to the works area. The marker flags
might for example comprise a set of a few vertical poles that are each of different
colour to denote increasing proximity to the exit / entry point. Alternatively, rather
than having a separate marker, the arm 7 may be provided in a set of different colours
to serve as the countdown marker to denote increasing proximity to the exit / entry
point.
[0021] In a simpler but much less convenient and far less versatile variation of the mounting
bracket 6, it may have a complete or broken collar-like form but not as a resilient
clip structure and be adapted to slidingly mount onto a box-beam 4 from one end rather
than being directly clip-mounted in a selected position. Nevertheless it is far preferred
that the mounting bracket 6 be a resilient clip structure as described and since it
is this that makes the device so practical and economic to use. For newly manufactured
road traffic safety barriers the arm-mounting bracket 6 of the guard 5 may be integrally
installed/ assembled to the barrier 1, suitably projecting from the box-beam 4 of
the guard 5.
[0022] The arm 7 is suitably an extrusion of a plastics, e.g. such as of nylon or polyethylene,
and has the form of a slim bar. As illustrated it resembles a thick plastics metre
ruler in its form and dimensions. It is flexible to be able to flex if struck by a
vehicle so that it does not itself represent a hazard and under extreme impact the
arm 7 will simply snap off. The mounting bracket 6 has a tubular socket 8 to de-mountably
hold the arm 7 so that the arm 7 may be replaced if it is damaged. The proximal end
of the arm 7 mounts slidingly into the socket 8 and a pair of clamping bolts 9 are
screwed in to engage and releasably secure the arm 7 in the socket 8. In practice
it is preferred to pre-assemble each arm 7 to the respective mounting bracket 6 off-site
to allow for speedy installation.
[0023] The arm 7 is marked for high visibility, ie with yellow and/ or red or other colours
that contrast strongly to the grey of the steel barrier and serve as hazard warning
markings. The distal end of the arm 7 away from the barrier 1 is adapted to receive
a rope, cord, tape or other elongate line strung from it parallel to the length of
the barrier 1. As illustrated the distal end of the arm 7 has a pair of notches 11
on an upper edge through which the line may pass and whereby the line may be wrapped
around the arm 7 and tied/ knotted in place at one end.
[0024] In the preferred embodiment as illustrated the socket 8 which holds the arm 7 is
on the top of the mounting bracket 6. In other embodiments it could be on the side
or even the underside of the bracket 6. Nevertheless it is preferably positioned so
as to minimise interference with the resilient jaw opening and closing action of the
limbs 6b of the bracket 6.
1. A guard for an elongate safety barrier to provide added protection for workmen who
are working alongside the safety barrier, the guard comprising a mounting bracket
to mount onto a safety barrier and that holds in use an arm whereby the arm projects
transversely from the barrier so that its distal end remote from the barrier is a
predetermined distance from the axis of the barrier to define a safe operational distance
from the safety barrier for workmen.
2. A guard for an elongate safety barrier as claimed in claim 1, wherein the arm is flexible
to be able to deflect if struck by a vehicle.
3. A guard for an elongate safety barrier as claimed in claim 1 or 2, wherein the arm
is an extrusion of a plastics material.
4. A guard for an elongate safety barrier as claimed in claim 1, 2 or 3, wherein the
distal end of the arm away from the barrier is adapted to receive a rope, oord, tape
or other elongate line that may be strung therefrom parallel to the length of the
barrier.
5. A guard for an elongate safety barrier as claimed in any preceding claim, wherein
the mounting bracket is configured to de-mountably hold the arm.
6. A guard for an elongate safety barrier as claimed in claim 5, wherein the mounting
bracket has a socket into which a proximal end of the arm mounts and which has one
or more releasable clamping means that engages and releasably secures the arm in the
socket.
7. A guard for an elongate safety barrier as claimed in any preceding claim, wherein
the mounting bracket has a resilient clip structure for quick assembly to a safety
barrier.
8. A guard for an elongate safety barrier as claimed in any preceding claim, wherein
the mounting bracket has a rape and form that is adapted to clippingly embrace around
a box beam at the top of a mobile safety barrier.
9. A guard for an elongate safety barrier as claimed in claim 8, wherein the mounting
bracket has a pair of limbs that may be resiliently flexed apart to be placed over
the respective opposing sidewalls of the beam.
10. A guard for an elongate safety barrier as claimed in any preceding claim, wherein
the mounting bracket is formed of spring steel.
11. A guard for an elongate safety barrier as claimed in any of claims 1 to 10, wherein
the mounting bracket has one or more limbs that flex to embrace the barrier and a
clasp or other releasable fastening means that releasably secures the one or more
limbs in place, closed around the barrier.
12. A guard for an elongate safety barrier as claimed in claims 11, wherein the mounting
bracket has a pair of opposing limbs that flex apart and close together to embrace
the barrier and the clasp or other releasable fastening means releasable secures an
end of one limb to an end of the other limb to hold the mounting bracket in place..
13. A guard for an elongate safety barrier as claimed in any preceding claim, wherein
a set of arms or flags are provided each for a respective one of a set of guards and
that are differently marked or coloured to provide a countdown marker for proximity
of an entrance / exit through the safety barrier.
14. A guard system for an elongate safety barrier to provide added protection from transport
vehicles for workmen who are working alongside the safety barrier, the guard system
comprising a plurality of lengths of elongate safety barrier having thereon a plurality
of guards, each guard comprising a mounting that holds in use an arm whereby the arm
projects transversely from the safety barrier so that its distal end remote from the
barrier is a predetermined distance from the axis of the barrier to define a safe
operational distance from the safety barrier for workmen.
15. A guard system as claimed in claim 14, wherein each length of elongate safety barrier
has an integral said mounting for the arm.