U.S. patent application number 11/608381 was filed with the patent office on 2007-06-21 for rail insulators.
This patent application is currently assigned to Airboss Railway Products Inc.. Invention is credited to Hartley Frank Young.
Application Number | 20070138311 11/608381 |
Document ID | / |
Family ID | 38162393 |
Filed Date | 2007-06-21 |
United States Patent
Application |
20070138311 |
Kind Code |
A1 |
Young; Hartley Frank |
June 21, 2007 |
RAIL INSULATORS
Abstract
Improved shoulder insulator for a rail seat assembly which
enables the rail seat to be pre assembled at the rail tie
fabrication plant into a preloaded position where a rail can be
laid on the tie on site. On site the rail clips can be moved to the
loaded position after the rail is placed in position. The rail seat
includes a concrete rail tie; a pair of rail clip support shoulders
cast in place in said rail tie each said shoulder having a rail
face between its external sides; a pair of shoulder insulators each
shaped to lie against the rail face of the rail shoulder; a pair of
rail clips each having a base section adapted to seat within the
rail clip support shoulder and a toe section adapted to seat on the
rail base, the toe section comprising a pair of bifurcated arms
extending from said base section and being bent in a curve so that
the toes lie adjacent but beyond the base; a pair of toe insulators
each adapted to fit about the toe of the rail clip to insulate the
clip from the rail base; the arrangement being such that when the
rail clip is in the preloaded position the toe insulator and the
toe of the clips do not project beyond the face of the shoulder
insulator so that a rail can be laid between the rail shoulders and
their associated insulators. The shoulder insulator is shaped to
lie against the rail face of the rail shoulder level with the gate
of the shoulder and abutting the location flange and incorporating
side arms that slip over the external retention rib of the
shoulders which is dimensioned so that when the shoulder insulator
top is pulled toward the rail and lifted up, the side arms clear
the retention clips and the top edge of the shoulder insulator post
clears the front of the toe insulator
Inventors: |
Young; Hartley Frank;
(Melton, AU) |
Correspondence
Address: |
Connolly Bove Lodge & Hutz LLP
Suite 800
1990 M Street, N.W.
Washington
DC
20036
US
|
Assignee: |
Airboss Railway Products
Inc.
Kansas City
MO
|
Family ID: |
38162393 |
Appl. No.: |
11/608381 |
Filed: |
December 8, 2006 |
Current U.S.
Class: |
238/107 |
Current CPC
Class: |
E01B 9/303 20130101 |
Class at
Publication: |
238/107 |
International
Class: |
E01B 21/04 20060101
E01B021/04 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 15, 2005 |
AU |
2005907023 |
Claims
1. A railroad tie and rail seat assembly for supporting a rail
which includes a) a concrete rail tie b) a pair of rail clip
support shoulders cast in place in said rail tie each said shoulder
having a rail face between its external sides, a clip gateway
through said rail face, a rail clip ramp leading from the rear of
the shoulder and terminating in the clip gateway at substantially
the level of the top of the rail base and an external vertical
retention rib on each side of the shoulder; c) a rail pad seated on
said rail tie between said support shoulders d) a pair of shoulder
insulators each shaped to lie against the rail face of the rail
shoulder level with the gate and abutting the location flange and
incorporating side arms that slip over the external retention rib
of the shoulders; e) a pair of rail clips each having a base
section adapted to seat within the rail clip support shoulder and a
toe section adapted to seat on the rail base, the toe section
comprising a pair of bifurcated arms extending from said base
section and being bent in a curve so that the toes lie adjacent but
beyond the clip base f) a pair of toe insulators each adapted to
fit about the toes of the rail clips to insulate the clips from the
rail base g) the arrangement being such that the rail clip has a
first stable position in the shoulder where the front of the toe
insulators do not project beyond the face of the shoulder insulator
so that a rail can be laid between the rail shoulders and their
associated insulators and a second stable position where the toe
insulator and the toes of the rail clip lie on the rail base.
2. A rail seat assembly as claimed in claim 1 in which the shoulder
incorporates an insulator retention rib on the rail face of the
shoulder on each side of the clip gateway.
3. A shoulder insulator for use in the tie assembly of claim 1
shaped to lie against the rail face of the rail shoulder level with
the gate of the shoulder and abutting the location flange and
incorporating side arms that slip over the external retention rib
of the shoulders which is dimensioned so that when the shoulder
insulator top is pulled toward the rail and lifted up, the side
arms clear the retention clips and the top edge of the shoulder
insulator post clears the front of the toe insulator.
4. A shoulder insulator as claimed in claim 3 in which the side
arms are resiliently biassed against the sides of the support
shoulder.
5. A shoulder insulator as claimed in claim 4 in which an up turned
flap is provided on the end of the side arm to act as a ratchet on
the surface of the support shoulder.
6. A support shoulder for use in the railroad tie and rail seat
assembly of claim 1 having a rail face between its external sides,
a clip gateway through said rail face, a rail clip ramp leading
from the rear of the shoulder and terminating in the clip gateway
at substantially the level of the top of the rail base and an
external vertical retention rib on each side.
7. A support shoulder as claimed in claim 6 which incorporates an
insulator retention rib on the rail face of the shoulder on each
side of the clip gateway.
8. A railroad tie and rail seat assembly for supporting a rail
which includes a) a concrete rail tie b) a pair of rail clip
support shoulders cast in place in said rail tie each said shoulder
having a rail face between its external sides, a clip gateway
through said rail face, a rail clip ramp leading from the rear of
the shoulder and terminating in the clip gateway at substantially
the level of the top of the rail base and an external horizontal
retention rib on the rail face on each side of the clip gateway; c)
a rail pad seated on said rail tie between said support shoulders
d) a pair of rail clips each having a base section adapted to seat
within the rail clip support shoulder and a toe section adapted to
seat on the rail base, the toe section comprising a pair of
bifurcated arms extending from said base section and being bent in
a curve so that the toes lie adjacent but beyond the clip base e) a
pair of rail insulators each having a shoulder portion that lies
between the rail base and the rail face of the rail shoulder and a
rail portion that lies between the rail and the toes of the rail
clips to insulate the clips from the rail base f) the rail
insulators incorporate gate ribs that define a clip gateway
corresponding to the clip gateway of the support shoulder and said
gate ribs abut the horizontal retention ribs on the rail face of
said support shoulder to prevent bending of the rail
insulators.
9. A support shoulder for use in the railroad tie and rail seat
assembly of claim 8 having a rail face between its external sides,
a clip gateway through said rail face, a rail clip ramp leading
from the rear of the shoulder and terminating in the clip gateway
at substantially the level of the top of the rail base and an
external horizontal retention rib on the rail face on each side of
the clip gateway.
Description
TECHNICAL FIELD
[0001] This invention relates to a rail fastening assembly of the
type where a rail is clamped to a rail seat by elastic rail
fasteners held in shoulders fastened to the tie and insulators
isolate the rail fastener and support shoulders from the rail. The
present invention addresses problems associated with the
insulators.
BACKGROUND
[0002] Concrete ties have been in use in some parts of the world
for a long time but it is only since 1985 that they have been able
to provide cost benefits for use in North America relative to
wooden ties.
[0003] One advantage of concrete ties is that the rail seats can be
pre assembled with only a few components to be added on site when
the rail is placed in position. The difficulty with this is that
the pre assembled components can become dislodged during transport
and some components still have to be positioned on the rail. The
rail seats usually comprises a rail pad that is positioned below
the rail, an abrasion resistant plate below the pad, rail clip
support shoulders on the field and gauge sides of the rail, an
elastic rail clip that seats in the support shoulder and bears down
on the rail base and an insulator that lies between the rail and
the rail clip and the support shoulder. The support shoulders are
precast in the rail tie and the rail pad is fitted between each
pair. Because the rail clips and insulators contact the rail when
fastened they cannot be placed in position until the rail has been
placed in position on the rail seat. Rail seat assemblies of this
type have been generally described in U.S. Pat. Nos. 5,110,046,
5,551,633 and 6,604,690. The rail clips in these assemblies are
either installed or loose and therefore had to be assembled on
site. U.S. Pat. No. 6,367,704 proposed using a modified support
shoulder so that the clip could be partially installed for
transport purposes where it was retained on the shoulder and then
able to be fully installed when the rail was placed in position. In
this arrangement the insulators still needed to be placed in
position manually before the clip could be fully installed. The
insulator is a one piece assembled part that lies on the rail
flange to separate the rail from the clip and extends down between
the rail flange and the support shoulder to provide insulation
between the shoulder and the rail.
[0004] U.S. Pat. No. 5,520,330 discloses a bent rod rail clip with
a two part insulator that enables the rail seat to be pre-assembled
at the tie plant.
[0005] WO02/31264 discloses a rail clip that has an insulator
encapsulating the toe of the rail clip that lies on the rail flange
to avoid the need to insert the insulator separately.
[0006] It is an object of this invention to provide a rail clip
insulator that enables easier assembly of a rail seat without
compromising rail fastening performance.
SUMMARY OF THE INVENTION
[0007] To this end the present invention provides a railroad tie
and rail seat assembly for supporting a rail which includes [0008]
a) a concrete rail tie [0009] b) a pair of rail clip support
shoulders cast in place in said rail tie each said shoulder having
a rail face between its external sides, a clip gateway through said
rail face, a rail clip ramp leading from the rear of the shoulder
and terminating in the clip gateway at substantially the level of
the rail base and an external vertical retention rib on each side
of the shoulder and optionally, an insulator location flange on the
rail face adjacent the gate; [0010] c) a rail pad seated on said
rail tie between said support shoulders [0011] d) a pair of
shoulder insulators each shaped to lie against the rail face of the
rail shoulder level with the gate and abutting the location flange
and incorporating side arms that clip over the external retention
rib of the shoulders; [0012] e) a pair of rail clips each having a
base section adapted to seat within the rail clip support shoulder
and a toe section adapted to seat on the rail base, the toe section
comprising a pair of bifurcated arms extending from said base
section and being bent in a curve so that the toes lie adjacent but
beyond the base [0013] f) a pair of toe insulators each adapted to
fit about the toe of the rail clip to insulate the clip from the
rail base [0014] g) the arrangement being such that when the rail
clip has a first stable position in the shoulder the toe insulator
where the toe of the clip sits does not project beyond the face of
the shoulder insulator so that a rail can be laid between the rail
shoulders and their associated insulators and a second stable
position where the toe insulator and the toes of the rail clip lie
on the rail base.
[0015] This arrangement enables the rail seat to be preassembled in
such a way that all the components are held in place on the tie
during transport from the tie production plant to the railway
installation site. Once the rail is placed in position on the tie,
the clips are simply pushed onto the rail base to secure the rail.
In the preloaded, transport position the base of the clip is only
partially inserted into the clip recess of the support shoulder.
This is made possible by replacing the conventional rail insulator
with two insulators one being attachable to the support shoulder to
insulate the shoulder from the rail and the other being attachable
to the rail clip to insulate the clip from the rail.
[0016] The shoulder insulator encloses the rail face of the support
shoulder and provides insulation between the rail base and the
support shoulder in a direction substantially normal to the rail
tie. The shoulder insulator has side arms extending along the sides
of the shoulder which are resiliently biassed against the sides of
the support shoulder to locate and retain the shoulder insulator on
the shoulder. The shoulder insulator also includes a gate similar
in shape to the shoulder gate for the rail clip and toe insulator
to pass through. The top of the shoulder insulator is abutted by
the front of the toe insulator to prevent it being lost during
transport when the rail clip is not fully loaded. The portion of
the shoulder insulator on either side of the gate may abut an
optional location flange that limits any vertical movement of the
insulator during heavy load conditions. It is also important that
the shoulder insulator is dimensioned to enable it to be removed
and replaced during track maintenance if the clip and toe insulator
are retracted to lie in the shoulder gate.
[0017] The toe insulator functions like a sled and the forward wall
is radiussed to enable the insulator to ride over the leading edge
of the rail base and up the inclined surface of the rail base. The
toe insulator incorporates a recess for each toe portion with
sufficient room to enable the bifurcated arms to be squeezed
together as they pass through the guideway of the shoulder. The toe
insulator is dimensioned relative to the support shoulder so that
in the preload position the toe insulator does not project beyond
the rail face of the support shoulder any further than the post
insulator so that the rail can be placed onto the rail seat without
disturbing the prefitted components. Once the rail is in place the
clips and the associated toe insulators can be pushed on to the
rail base to the fully loaded or installed position. A preferred
toe insulator is disclosed in copending application
PCT/AU2004/001280
[0018] When the clip and toe insulator are in the fully loaded
position the rear end of the insulator preferably remains within
the gateway of both the shoulder and the shoulder insulator, so
that any axial movement of the rail will cause the toe insulator to
contact the sides of the shoulder and shoulder insulator gates and
consequently provide a creep resisting force. Without this
resistance the sideward creep force would be resisted by the clip
which is flexible in that direction and the available creep
resisting force provided by the clip is lower than that provided by
the shoulder which is rigidly fixed to the rail tie. The shoulder
insulator is rigidly attached to the shoulder so that sideways
force applied to this insulator is transmitted directly to the
shoulder. This feature of the clip and toe insulator increases
resistance of the total assembly to the effects of rail creep.
[0019] While this invention is primarily aimed at providing
benefits for original track installations it also gives ongoing
benefits for track maintenance. When the rail and pads need to be
changed it is a simple matter to move the clip and toe insulator
back into the first stable position for removal of the rail &
then to press the clip and toe assemblies back into the second
stable position on the rail base when the replacement is
complete.
[0020] If only the shoulder insulator needs to be removed it is
able to be removed by twisting the shoulder insulator so that the
side arms are swiveled clear of the retention rib and the locating
flange so that the insulator can then be pulled clear of the
shoulder.
[0021] This invention is also applicable to single piece insulators
that do away with the need for a toe insulator by providing a
portion that lies on the rail base.
[0022] In another aspect this invention is concerned with damage to
insulators particularly one piece insulators caused by the movement
of the insulator in curved sections of track. Where the support
shoulders are much wider than the toe of the clip only a small
central portion of the insulator is under vertical downward
pressure while the portion of the insulator lying between the
shoulder and the rail may be squeezed and pushed upwardly resulting
in a banana effect on the insulator. To inhibit this behaviour,
upstops are provided on the support shoulder to engage the outer
portions of the insulator to inhibit the bending of the insulators.
These stops need only be provided on the field side of the rail
seat.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Preferred embodiments of the invention will now be described
with reference to the drawings in which
[0024] FIG. 1 is a side view of a rail seat assembly of this
invention;
[0025] FIG. 2 is a plan view of one embodiment of the shoulder
insulator of this invention;
[0026] FIG. 3 is a front view from the rail of the shoulder
insulator of FIG. 4;
[0027] FIG. 4 is a side view of the shoulder insulator of FIG.
4;
[0028] FIG. 5 is a plan view of the shoulder insulator attached to
a shoulder;
[0029] FIG. 6 is a side view of the shoulder insulator in position
on a shoulder;
[0030] FIG. 7 illustrates the removal or fitting of the shoulder
insulator;
[0031] FIG. 8 illustrates a one piece rail and shoulder insulator
used in a second aspect of the invention;
[0032] FIG. 9 is a plan view of the insulator of FIG. 8;
[0033] FIG. 10 is a sectional view 10-10 of FIG. 9;
[0034] FIG. 11 is a sectional view 11-11 of FIG. 9;
[0035] FIG. 12 illustrates the one piece insulator of FIG. 8
installed with a shoulder of this invention.
[0036] The rail seat comprises a concrete rail tie 5 into which has
been cast the rail clip support shoulders 10. Between the two
shoulders 10 are positioned a rail pad 3 and beneath that a wear
resisting plate 4. The rail 2 seats on the rail pad 3. This rail
pad may incorporate a recess at its edge adjacent the shoulder 10
to accommodate a deep post insulator 50. The rail pad is preferably
as described in Australian specification 2004201448. The base 31 of
rail clip 30 is securely held within the shoulder 10 and the toe
section 32 seats within the toe insulator 40 that lies on the rail
base 2. The deep post insulator 50 is attached to shoulder 10 and
lies between the rail base 2 and the shoulder 10 and extends down
to the rail pad 3.
[0037] The rail clip 30 as illustrated in FIGS. 1 is made from a
flat metal stamping bent into its final 3 dimensional state. The
rail clip consists of a base web 31 which bifurcates into arms 34
that end in the toe portions 32. The ends 36 of the toe portion 32
are shaped to enable to clips to be held in a partially applied
position in the shoulder 10. The rail clip and shoulder are
designed so that the clip has two stable positions in the shoulder
namely a preloaded position where a rail can be placed in position
on the rail seat and a fully loaded position in which the toes of
the rail clip are on the rail base.
[0038] The toe insulator 40 shown in FIGS. 1 is conceptually like a
sled encompassing the toe portion 32 of clip 30. The toes 32 of the
clip enter the toe insulator 40 vertically and provide a downward
force on the insulator 40. The insulator 40 has a front wall with
sides shaped to pass through the gate 12 of the shoulder 10 and the
gate 52 of the shoulder insulator 50. The lower front wall of the
toe insulator is angled to assist the insulator to ride up the rail
base 2 particularly when the tie is lower than the final position.
The lower surface of the toe insulator is flat to provide maximum
contact area with the rail base 2. The rear of the base of the toe
insulator is upwardly inclined to assist in the movement of the
insulator. The toes 32 of the clip, seat in the toe recesses formed
by the centre web that extends between the front wall and the rear
wall of the toe insulator. This web reinforces the toe insulator
and strengthens the front and rear walls to ensure that the
insulator 40 can withstand the forces applied during installation
of the clip onto the rail base. As the clip is moved forward the
insulator 40 is pushed forward by the radiussed portion of the clip
toe 32 abutting the forward wall of the toe insulator. And when the
clip 30 is retracted the free end of the toe 32 abuts the rear wall
and the insulator 40 moves rearwardly with the clip 30.
[0039] The two part insulator in combination with the clip and
shoulder of this invention enables the rail seat to be preassembled
at the concrete tie plant as shown in FIG. 6. The clip is in the
preloaded position and the insulator 40 is locked in by the toes 32
and the insulator 50 is attached to the rail face of shoulder 10.
The base 31 of the clip has entered the clip slot in the shoulder
10. In this preassembled position the rail tie can be transported
without the risk of components being lost. On site once the tie is
in position the rail can be moved into position and the only
installation step needed is to push the clip toward the rail which
takes the toe portion 32 of the clip and insulator 40 onto the rail
base and the base of the clip 31 seats in its loaded position in
shoulder 10 to secure the clip in place.
[0040] The angled base of the installed shoulder and the angle of
the clip base in the shoulder are chosen so that the frictional
engagement of the clip base keeps the clip located on the rail
base.
[0041] The shoulder insulator 50 has a rail face 51 which abuts the
rail base 2 and has a gate 52 matching the shoulder gate 12. The
corner pieces 53 on either side of the gate incorporate a chamfered
surface 54 that guides the rail into position. The arms 55 are
resiliently biassed against the sides of the support shoulder and
are shaped to fit around the corners of the shoulder 10 and the
recess 56 fits over the vertical rib 18 to locate and retain the
insulator in position. When the shoulder 10 is cast into the
concrete tie the rib 18 is inclined to the vertical so that it
wedges against the end 57 of the arm 55 to provide a snug fit. A
thin upturned flap 58 is provided on the end 57 to act as a ratchet
on the rough surface of the cast metal shoulder 10 to ensure that
the shoulder insulator 50 is retained in place. This retention
system also ensures that the shoulder insulator is retained in
place when the rail tie is transported partly assembled from the
tie plant. A ledge 59 is provided on the lower edge of the face 51
to engage the bottom edge of the rail base 2 and resist upward
movement of the insulator. The corner pieces 53 lie under the up
stops 13 on shoulder 10 to prevent vertical movement or banana
flexing of the shoulder insulator 50.
[0042] The shoulder insulator is removed as shown in FIG. 7 by
inclining it toward the rail and then withdrawing so that the ledge
59 clears the rail base edge and the corner pieces clear the
upstops 13 and the arms 55 are tilted so that the ends 57 clear the
top of the vertical retention ribs 18 and the post clears the front
of the toe insulator 40. The shoulder insulator can be inserted in
reverse sequence. The shoulder insulator can be fitted and removed
by hand or with the use of a tool that grips the side arms 55 and
then twists and flexes the insulator 50 so that it clears the rail
base, retention rib 18, toe insulator 40 and location flange 13.
The one piece insulator 60 shown in FIG. 9 comprises the shoulder
insulator portion 61 which lies between the rail and the support
shoulder; the rail insulator portion 65 which lies on the rail
base; and the corner pieces 63 which enclose the corners of the
shoulder 10. The gate 62 lies between the gate ribs 64 and
coincides with the gate 12 of the shoulder 10. The gate ribs 64
abut the up stops 13 of the shoulder to prevent bending of the
insulator particularly on the field side of the rail seat. The rail
portion 65 incorporates the central bearing surface 66 on which the
toes of the rail clip apply a downward force.
[0043] With the one piece insulator 60 the rib 18 and the
attachment arms on the insulator are not needed because the rail
clip holds the insulator 60 in position relative to the shoulder
10. The upstops 13 stabilize the position of the insulator 60 by
abutting the gate ribs 64.
[0044] Those skilled in the art will realize that the present
invention provides a rail tie assembly that is easy to fabricate
and assemble and reduces the time and cost of installation.
Although two particular embodiments have been described those
skilled in the art will realize that variations and modifications
may be made without departing from the core teachings of the
invention.
* * * * *