DISPOSITIF ISOLANT LE RAIL DE LA BRIDE DE FIXATION ET DE L'ANCRAGE DE CETTE BRIDE

DEVICE SUITABLE FOR USE IN A RAILWAY RAIL-AND-FASTENING ASSEMBLY TO INSULATE A RAIL FROM A RAIL CLIP AND FROM AN ANCHORAGE FOR THE CLIP

Abrégé anglais

Abstract:
A device suitable for use in a railway rail-and-
fastening assembly to insulate a rail from a rail clip and
from an anchorage for the clip includes an elongate plate-
like portion, a portion depending from one side of it and
two lugs projecting from the depending portion away from
the plate-like portion near opposite ends thereof. In
contrast to prior proposals, the device is asymetrical, a
flat surface on the top of the plate like portion having
its center nearer one end of that portion than the other
end. A ramp surface leads up to the flat surface from at
least other end. The device i preferably made wholly
of glass fibre-reinforced nylon and the thickness of the
plate-like portion is preferably at least 5 millimeters

Revendications

CLAIMS:
1. A device suitable for use in a railway rail-and-
fastening assembly to electrically insulate a rail from a rail
clip, which bears downwardly upon the upper surface of the rail
flange, and from an anchorage, beside the rail flange, for the
rail clip, the device including a first, elongate, plate-like,
portion for positioning on the rail flange, a second portion
depending from one side of the first portion, for positioning
between the edge of the rail flange and the anchorage, and two
lugs projecting from the second portion in the same direction
as one another away from the first portion and near opposite
ends thereof, said lugs serving to project on opposite sides
of the anchorage to limit movement of the device along the
rail, said first portion comprising, on its upper face, a flat
surface upon which the clip is to bear, the centre of this
flat surface being nearer to one end of said first portion
than it is to the other end of said first portion, and said
first portion further comprising a ramp surface leading up to
said flat surface from said other end of the first portion.
2. A device according to claim 1 having another and
steeper ramp surface leading up to said flat surface from said
one end of the first portion.
3. A device according to claim 1 or 2 in which the
thickness of the electrically insulating material in the first
portion is more than 5 millimeters.
4. A device according to claim 1 or 2 in which the
thickness of the electrically insulating material in the first
portion is more than 6 millimeters.

5. A device according to claim 1 or 2 in which the
thickness of the electrically insulating material in the first
portion is more than 7 millimeters.
6. A device according to claim 1 or 2 in which the
thickness of the electrically insulating material in the first
portion is more than 8 millimeters.
7. A device according to claim 1 made wholly of
fibre-reinforced plastic material.
8. A device suitable for use in a railway rail-and-
fastening assembly to insulate a rail from a rail clip and
from an anchorage for the clip, comprising a single piece of
fibre-reinforced plastic material, having a first portion which
is elongate, trapezoidal and plate-like, with a thickness of
at least 5 mm., a second portion depending from one side of
the first portion, and first and second lugs projecting from
the second portion in the same direction as one another away
from the first portion and near first and second ends, respect-
ively, thereof, said first portion comprising on its upper
face an elongate flat surface, the center of which is sub-
stantially nearer to said first end of said first portion
than to said second end of said first portion, a first ramp
surface leading up to said flat surface from said first end
of said first portion, a second ramp surface leading up to
said flat surface from said second end of said first portion,
said first ramp surface having an angle from the horizontal
substantially greater than the angle of said second ramp
surface from the horizontal.
9. A device according to claim 1, 2 or 8 made wholly

of fibre-reinforced nylon.
10. A device according to claim 1, 2 or 8 made wholly of
glass-fibre-reinforced nylon.
11. A railway rail-and-fastening assembly comprising an
electrically conductive rail foundation, an electrically
insulating pad placed on the rail foundation, a rail standing
on the pad, an anchorage beside the rail flange, a rail clip
held by the anchorage, a device according to claim 1, 2 or 7
with its first portion on the rail flange and its second
portion between the edge of the rail flange and the anchorage
and with the clip bearing downwardly on the upper side of its
first portion.
12. A device according to claim 2 made wholly of fibre-
reinforced plastic material.
13. A railway rail-and-fastening assembly comprising an
electrically conductive rail foundation, an electrically
insulating pad placed on the rail foundation, a rail standing
on the pad, an anchorage beside the rail flange, a rail clip
held by the anchorage, a device according to claim 8 or claim
12 with its first portion on the rail flange and its second
portion between the edge of the rail flange and the anchorage
and with the clip bearing downwardly on the upper side of its
first portion.

Description

10679~7Z
AN ELECTRI Q L INSULATOR SUITABLE FOR USE IN
A RAILWAY RAIL-AND-FASTENING ASSEMBLY TO
INSULATE A RAIL FROM A RAIL CLIP AND FROM
AN ANCHORAGE FOR THE CLIP
According to a first aspect of the invention~
there is provided a device suitable for use in a railway
rail-and-fastening assembly to electrically insulate a
rail from a rail clip, which bears downwardly upon the
upper surface of the rail flange, and from an anchorage,
beside the rail flange, for the rail clip, the device in-
cluding a first, elongate, plate-like, portion for
~positioning on the rail flange, a second portion depending
from one side of the first portion, for positioning~between
the~edge of the rail flange and the anchorage, and two lugs
projecting from the second portlon in the same direction as
one another away from the first portion and near opposite
ends thereof, said lugs serving to project on opposite
sides of the anchorage to limit movement of the device
along the rail, said first portion comprising, on its upper
face, a flat surface upon which the clip is to bear, the
centre of this flat surface being nearer to one end of said
first portion than it is to the other end of said first
portion, and said first portion further comprising~a ramp
surface leading up to said flat surface from said other end
of the first portion.
Preferably, the device has another and steeper
ramp surface leading up to said flat surface from ~said one
end of the first portion.
The de~ice may be made wholly of fibre~reinforced
~ 30 pla5tics material.
-~ The thickness of ehe eloctrlcal1y insu1atiAg

~)674~
-- 2
material in the first portion is preferably more than
5 mm,/ better more than 6 mm., better still more than 7 mm.
and even better more than 8 mm.
According to a second aspect of the invention,
there is provided a device suitable for use in a railway
rail-and-fastening assembly to insulate a rail from a rail
clip and from an anchorage for the clip, comprising a
single piece of fibre-reinforced plastic material, having
a first portion which is elongate, trapezoidal and plate- "
like, with-a thickness of at least 5 mm., a second portion
depending from one side o the first portion, and first
and second lugs projecting from the second~portion in the
same direction as one another away from the first portion
and near first and second ends, respectively, thereof,
said first portion comprising on its upper face an elongate
( flat surface, the center of which is substantially nearer
to said first end of said first portion than to said second
end of said first portion, a first ramp surface leading up
to said flat surface from said first end of said first
portion, a second ramp surface leading up to said flat
surface from said second end of said first portion, said
first ramp surface havlng an angle from the hori~ontal sub-
stantially greater than the angle of said second ramp
surface from the horizontal.
The device according to the first or second
aspect of the invention may be made wholly of fibre-rein-
forced (preferably glass fibre-reinforced) nylon.
According to a third aspect of the invention,
there is provided a railway rail-and-fastening assembly
comprising an electrically conductive rail foundation, an
electrically insulating pad placed on the rail foundation,
a rail standing on the pad, an anchorage beside the rail
flange, a rail clip held by the anchorage, a device accord-
ing to the first or second aspect of the invention with its
first portion on the rail flange and its second portion
between the edge of the rail flange and the anchorage and
with the clip bearing downwardly on the upper side o~ its
first portion.
An example of a device according to the first and
.
.

~()6747;~ ~
~ 3/4/5
second aspects of the invention is described be.low with
reference to the accompanying drawing, in which:-
Figure 1 shows a plan view,
Fiyure 2 shows an end elevation, and
Figure 3 shows a side elevation, of an electrical
insulator.
The insulator is made wholly of glass fibre-
reinforced nylon and is made by moulding such material in
a single piece which includes an elongate, trapezoidal,
fir=t, plate-
.
~ :
:: :
:
:: : : : :
~: : :
:: :: : :
~ -
,~.~,
~ : ~ . , :
'

~06747Z
. ` '
1 - like~ portion 1 for positioning on the ~lange of a
railway rail which stands on an electrlcally in-
- sulatin~ pad placed on an electrically conductive
foundation for the rail, for example a concrete
railway sleeper. It further includes a second portion
2 depending from one side of the first portion, the
longer of the two parallel sides, for ~positioning
between the edge of the rail flange and an anchorage
for a rail clip, the anchorage being for example
made of cast malleable iron with a portion embedded ~n
the sleeper where the latter is of concrete. A rail
clip, made by bending a steel bar of circular cross-
; section, has one portion held by the anchorage and
- another portion bearing down~ardly on the upper side
o the first portion of the Lnsulator. The insulator
- electrically insulates the rail from the clip~and from
the anchorage~ Two lugs 3 pro~ect from the second
portion 2 in the same direction as one another away
` from the first portion 1 near opposite ends of the first
portion 1 and in use of the insulator they pro~ect on
opposite sides of the anchorage to~limit~movement of
the insulator along the rail. -
; - The insulator includes, on lts face which is
uppermost when it is in use, a rectangular flat surface
4, over the whole of which the thickness of the first
portion l is 8 mm~boun~ed at two opposite sides by the
', :,

~L06~47z
1 - lines 5, the centre 6 of this ~lat surface being dis-
placed, in the direction in which the rail-extends
- when the insulator is in use, by a distance X from a
point 7 mldway between the lugs 3. Thus the centr~
of th~ flat surface 4 is nearer to that end o~ the
first portion which is shown uppermost in Flgure 1
than it is to:the other end of the first portion~
::
There are a short and steep ramp surface 8 and:a
longer and less steep ramp surface 9 extending from
.
10 ~ opposite ends of the first portion up to the flat ~
surface 4. Part of the clip rides up the ramp ~ ¦
: surface 9 in driving the clip into position. When
fully driven, the area of contact between it and the
lnsulator is substantially symmetrically positioned ~ ~ :
~: ~ with regard to the length of;:~the flat portion~4 of
: - the insulator but not with regard to the length of
the entire insulator.
:
:
7.
` '. . :
.