U.S. patent application number 09/366040 was filed with the patent office on 2001-11-22 for switch stoneblower.
Invention is credited to HANSEN, KEVIN A., PERRY, WILLIAM E..
Application Number | 20010042487 09/366040 |
Document ID | / |
Family ID | 23441424 |
Filed Date | 2001-11-22 |
United States Patent
Application |
20010042487 |
Kind Code |
A1 |
PERRY, WILLIAM E. ; et
al. |
November 22, 2001 |
SWITCH STONEBLOWER
Abstract
A track maintenance vehicle having a workhead that is pivotally
mounted to the superstructure at its upper end. The workhead
includes a blowing tube mounted at its lower end and a vertical
cylinder that is selectively extendable and retractable to control
the height of the blowing tube. The vehicle includes a control
system that controls the height of the blowing tube as well as the
left/right and fore/aft positions of the workhead. The track
maintenance vehicle further includes an automated height control
system that automatically extends and retracts the vertical
cylinder to position the blowing tube at a uniform height despite
its lateral disposition.
Inventors: |
PERRY, WILLIAM E.;
(LUDINGTON, MI) ; HANSEN, KEVIN A.; (LUDINGTON,
MI) |
Correspondence
Address: |
WARNER NORCROSS & JUDD LLP
900 OLD KENT BUILDING
111 LYON STREET, N.W.
GRAND RAPIDS
MI
49503-2487
US
|
Family ID: |
23441424 |
Appl. No.: |
09/366040 |
Filed: |
August 2, 1999 |
Current U.S.
Class: |
104/2 ;
104/7.1 |
Current CPC
Class: |
E01B 27/18 20130101 |
Class at
Publication: |
104/2 ;
104/7.1 |
International
Class: |
E01B 001/00; E01B
027/17; E01B 029/04 |
Claims
The embodiments of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. A track maintenance vehicle comprising: a superstructure; a
workhead mounted on said superstructure, said workhead having an
upper end pivotally attached to said superstructure at a pivot
location and a lower end terminating in a blowing tube; and an
actuating means for controlling pivotal movement of said workhead,
said actuating means carried by said superstructure and operable to
cause pivotal movement of said workhead with respect to said
superstructure about said pivot location.
2. The vehicle of claim 1 wherein said superstructure has an upper
extent, said pivot location being located toward said upper
extent.
3. The vehicle of claim 2 wherein said workhead includes a vertical
cylinder, said blowing tube mounted on said vertical cylinder, and
further comprising a control means for extending and retracting
said vertical cylinder to control a height of said blowing
tube.
4. The vehicle of claim 3 wherein said workhead includes first and
second portions, said second portion capable of pivotal movement
with respect to said first portions, said workhead further
including a bias means for biasing said second portion into a home
position with respect to said first portion.
5. The vehicle of claim 4 wherein said actuating means includes a
lateral adjustment means for controlling a lateral position of said
workhead.
6. The vehicle of claim 5 wherein said lateral adjustment means
includes a lateral cylinder extending between said superstructure
and said workhead, said lateral cylinder being extendable and
retractable to pivot said workhead about said pivot location and
vary a lateral disposition of said workhead.
7. The vehicle of claim 6 wherein said actuating means includes a
means for sensing said lateral disposition of said workhead.
8. The vehicle of claim 7 wherein said actuating means includes a
longitudinal adjustment means for controlling a longitudinal
position of said workhead, said longitudinal adjustment means
including a longitudinal cylinder extending between said
superstructure and said workhead, said longitudinal cylinder being
extendable and retractable to pivot said workhead about said pivot
location and vary a longitudinal disposition of said workhead.
9. The vehicle of claim 8 comprising at least two of said workheads
and at least two of said actuating means, each of said actuating
means being uniquely associated with and controlling the
disposition of one of said workheads.
10. The vehicle of claim 9 wherein said blowing tubes each define
an exit opening, said workheads arranged in corresponding pairs,
said corresponding workheads being spaced apart and aligned in a
longitudinal direction, said exit openings of said blowing tubes of
said corresponding workheads opening toward one another.
11. The vehicle of claim 1 further comprising a means for
positioning said blowing tube at a uniform height despite pivoting
movement of said workhead, said means for positioning including
means for adjusting a height of said workhead to compensate for
said lateral disposition.
12. A workhead for use in maintaining a railroad track comprising:
a vertically elongated body having upper and lower ends; a pivot
means for permitting lateral and longitudinal pivotal movement of
the body, the pivot means attached to said upper end and adapted to
mount to a superstructure; and a blowing tube mounted to said lower
end of said body.
13. The workhead of claim 12 wherein only a single blowing tube is
mounted to said body.
14. The workhead of claim 13 wherein said body includes a vertical
cylinder, said cylinder being extendable and retractable to permit
selective vertical movement of said blowing tube.
15. The workhead of claim 14 wherein said vertical cylinder
includes a cylinder and a rod, said blowing tube affixed to and
carried by said rod.
16. The workhead of claim 15 wherein said body includes a sleeve
having an upper end and a lower end, said vertical cylinder mounted
within said sleeve and protruding from said lower end of said
sleeve, said pivot means mounted to said upper end of said
sleeve.
17. The workhead of claim 15 wherein said body includes a sleeve
having an upper end and a lower end, said vertical cylinder
pivotally mounted within said sleeve and protruding from said lower
end of said sleeve, said pivot means mounted to said upper end of
said sleeve.
18. The workhead of claim 17 wherein said body includes a bias
means for biasing said cylinder in a home position with respect to
said sleeve.
19. The workhead of claim 18 further comprising a sensor means for
sensing relative movement of said vertical cylinder with respect to
said sleeve.
20. The workhead of claim 19 further comprising an actuating means
for controlling pivotal movement of said body about said pivot
means, said actuating means adapted to be carried by the
superstructure and operable to cause pivotal movement of said
workhead with respect to the superstructure about said pivot
means.
21. The workhead of claim 20 wherein said actuating means includes
a lateral adjustment means for controlling a lateral position of
said workhead.
22. The workhead of claim 21 wherein said lateral adjustment means
includes a lateral cylinder adapted to extend between the
superstructure and said body, said lateral cylinder being
extendable and retractable to pivot said workhead laterally about
said pivot means and vary a lateral disposition of said
workhead.
23. The workhead of claim 22 wherein said actuating means includes
a means for sensing said lateral disposition of said workhead.
24. The workhead of claim 23 wherein said actuating means includes
a longitudinal adjustment means for controlling a longitudinal
position of said workhead, said longitudinal adjustment means
including a longitudinal cylinder adapted to extend between the
superstructure and said body, said longitudinal cylinder being
extendable and retractable to pivot said workhead longitudinally
about said pivot means and vary a longitudinal disposition of said
workhead.
25. The workhead of claim 24 further comprising means for
positioning said blowing tube at a uniform height despite pivoting
movement of said workhead, said means for positioning including
means for adjusting a height of said workhead to compensate for
said lateral disposition.
26. The workhead of claim 25 wherein said means for positioning
extends and retracts said vertical cylinder in response to data
collected from said means for sensing a lateral disposition.
27. A track maintenance vehicle comprising: a superstructure
supported on a plurality of wheels, said support structure
including a first portion located toward a top of the vehicle and a
second portion located vertical lower than said first portion; a
vertically elongated workhead, said workhead having an upper end
pivotally attached to said first portion of superstructure at a
pivot location and a lower end terminating in a single blowing
tube; and an actuating means for controlling pivotal movement of
said workhead about said pivot location, said actuating means
mounted to said second portion of said superstructure and operable
to cause pivotal movement of said workhead with respect to said
superstructure about said pivot location.
28. The vehicle of claim 27 wherein said actuating means includes a
lateral adjustment means for controlling a lateral position of said
workhead, said lateral adjustment means including a lateral
cylinder extending between said superstructure and said workhead,
said lateral cylinder being extendable and retractable to pivot
said workhead about said pivot location and vary a lateral
disposition of said workhead.
29. The vehicle of claim 28 wherein said actuating means includes a
longitudinal adjustment means for controlling a longitudinal
position of said workhead, said longitudinal adjustment means
including a longitudinal cylinder extending between said
superstructure and said workhead, said longitudinal cylinder being
extendable and retractable to pivot said workhead about said pivot
location and vary a longitudinal disposition of said workhead.
30. The vehicle of claim 27 wherein said actuating means includes:
a lateral sleeve movably mounted to said second portion of said
superstructure; a lateral cylinder having a first end mounted to
said second portion of said superstructure and a second end mounted
to said sleeve, said lateral cylinder being extendable and
retractable to move said lateral sleeve laterally with respect to
second portion; and a longitudinal cylinder having a first end
mounted to said sleeve and a second end mounted to said workhead,
said longitudinal cylinder being extendable and retractable to move
said workhead longitudinally with respect to said
superstructure.
31. The vehicle of claim 30 comprising at least two of said
workheads and at least two of said actuating means, each of said
actuating means being uniquely associated with and controlling
movement of one of said workheads.
32. The vehicle of claim 31 wherein said blowing tubes each define
an exit opening, said workheads arranged in corresponding pairs,
said corresponding workheads being spaced apart and aligned in a
longitudinal direction, said exit openings of said blowing tubes of
said corresponding workheads opening toward one another.
33. The vehicle of claim 32 wherein said actuating means includes a
means for sensing said lateral disposition of said workhead.
34. The vehicle of claim 33 further comprising a means for
positioning said blowing tube at a uniform height despite pivoting
movement of said workhead, said means for positioning including
means for adjusting a height of said workhead to compensate for
said lateral disposition.
35. The vehicle of claim 34 wherein said workhead includes a
vertical cylinder, said blowing tube mounted to said vertical
cylinder, and wherein said means for adjusting a height includes a
vertical cylinder control means for extending and retracting said
vertical cylinder.
36. The vehicle of claim 35 wherein said workhead includes a
workhead sleeve having an upper end and a lower end, said upper end
of said workhead sleeve pivotally mounted to said first portion of
said superstructure, said vertical cylinder pivotally mounted
within said workhead sleeve and protruding from said lower end of
said workhead sleeve, said workhead including a bias means for
biasing said vertical cylinder in a home position with respect to
said workhead sleeve, said workhead further comprising a sensor
means for sensing relative movement of said vertical cylinder with
respect to said sleeve.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to railroad track maintenance
equipment and more particularly to a vehicle for performing
maintenance on the bed of a railroad track.
[0002] It is important for railroad track to remain substantially
level and uniform along its length. Although slight and gradual
variations in the profile of the track are typically acceptable,
rapid or severe longitudinal or lateral variations can have a
significant impact on the performance of the track. As a result,
significant efforts are made to maintain the railroad track with a
level profile. To this end, railroad track is typically laid on a
bed of ballast stones, which provide a firm foundation for the ties
or sleepers. Once the track is leveled, the ballast stone bed helps
to preserve the level of the track for a relatively long period of
time. Nonetheless, over extended use the stones shift, crumble or
otherwise degrade causing undesired variations in the track, such
as bows, twists and undulations. For example, stone under one end
of a particular tie may shift or crumble under repeated train
passes causing that end of the tie to settle. As the tie settles,
it creates a low spot in the rail, making travel over the rail
rough and, depending on the severity, possibly increasing the
likelihood of a derailment.
[0003] To maintain the level of a railroad track, it is necessary
to perform periodic maintenance on the railroad track bed. One
particularly effective method for maintaining a railroad track bed
is to supply new ballast stones to the bed beneath settled ties.
Typically, the new ballast stones are blown under the tie using
compressed air. As a result, this method is commonly referred to as
"stoneblowing." Stoneblowers have been in use for years and provide
significant advantages over other maintenance techniques. For
example, experience has revealed that track that is maintained by
stoneblowing may retain a level profile significantly longer than
track maintained using conventional "tamping" methods.
[0004] Stoneblowing is typically performed by a track maintenance
vehicle, called a stoneblower. A stoneblower typically includes a
jack for lifting the railroad track and associated ties and at
least one workhead for delivering new stone under the lifted ties.
A stoneblower workhead typically includes a pair of blowing tubes
that can be thrust into the ballast adjacent to the tie to deliver
new stone. The blowing tubes are positioned on the workhead to
straddle the rail and supply stone on opposites sides of the rail.
In use, the blowing tubes are typically aligned with the edge of
the tie and include openings toward their lower ends to allow
ballast to blown directly beneath the tie. A conventional workhead
is mounted toward the bottom of the vehicle on a pair of movable
carriages. The carriages permit a limited range of lateral and
longitudinal movement of the workhead. Conventional stoneblowers
are not well-suited for use in maintaining switches and other
complex track configurations. The double carriage arrangement of a
conventional workhead often fails to provide enough adjustment to
accommodate the complex tie and rail arrangements found in switches
and the like. Also, the dual blowing tube workhead is not
well-suited for treating many locations in a switch as one blowing
tube may impede insertion of the other into narrow locations.
SUMMARY OF THE INVENTION
[0005] The aforementioned problems are overcome by the present
invention wherein a stoneblower is provided with a vertically
extended workhead that pivots from a point located near the top of
the stoneblower. The position of the workhead is controlled by a
pair of hydraulic cylinders operatively connected to a central
portion of the workhead. In a preferred embodiment, the workhead
includes a single blowing tube extending downwardly from the bottom
of the workhead.
[0006] In a more preferred embodiment, the stoneblower includes a
computerized control system for controlling the position of the
workheads. The control system includes an automated height control
system that automatically positions the blowing tube at the desired
height regardless of the left/right (or lateral) position of the
workhead. The uniform height control system automatically adjusts
the position of the vertical cylinder to compensate for changes in
the height of the blowing tube that would otherwise result from
arcuate movement of the workhead.
[0007] In an even more preferred embodiment, the workhead includes
two pair of workheads, a first pair located over the left rail and
a second pair located over the right rail. Each pair of workheads
includes a forward workhead having a rearwardly opening blowing
tube and a rear workhead having a forwardly opening blowing tube.
The forward and rear workheads are adapted to align with the
forward and rearward faces of a tie, respectively.
[0008] The present invention provides an effective stoneblower that
is particularly well suited for maintaining switches and other
complex track configurations. The workheads are easily adjustable
to treat even narrow locations in the rail. Because the workhead
pivots near the top of the vehicle, increased fore/aft and
left/right movement is possible with only a relatively small amount
of vertical movement. The pivotal mounting permits a broad range of
movement of the workhead without requiring a correspondingly broad
range of movement in the actuating assembly. In fact, the workhead
can even treat locations outside of the lateral profile of the
vehicle. Further, the automated height control system permits left
and right adjustment of the workhead without requiring manual
adjustment of the height of the workhead.
[0009] These and other objects, advantages, and features of the
invention will be readily understood and appreciated by reference
to the detailed description of the preferred embodiment and the
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1a is a side elevational view of a first portion of a
stoneblower in accordance with a preferred embodiment of the
present invention;
[0011] FIG. 1b is a side elevational view of a second portion of
the stoneblower;
[0012] FIG. 2 is an enlarged side elevational view of a central
portion of the stoneblower;
[0013] FIG. 3 is a top plan view of a central portion of the
stoneblower;
[0014] FIG. 4 is a partial sectional view of the stoneblower with
portions removed taken along line IV-IV of FIG. 2;
[0015] FIG. 5 is front elevational view of the workhead;
[0016] FIG. 6 is a side elevational view of the workhead;
[0017] FIG. 7 is a top plan view of the workhead;
[0018] FIG. 8 is a front elevational view of the vertical
cylinder;
[0019] FIG. 9 is a side elevational view of the vertical
cylinder;
[0020] FIG. 10 is a section view of the vertical cylinder taken
along line X-X of FIG. 8;
[0021] FIG. 11 is a top plan view of the vertical cylinder;
[0022] FIG. 12 is a t op plan view of the longitudinal cylinder
assembly;
[0023] FIG. 13 is a front elevational view of the longitudinal
cylinder assembly;
[0024] FIG. 14 is a sectional view of the longitudinal cylinder
assembly taken along line XIV-XIV of FIG. 12;
[0025] FIG. 15 is a side elevational view of a portion of the
stoneblower showing the workhead actuating assembly;
[0026] FIG. 16 is top plan view of a portion of the stoneblower
showing the workhead actuating assembly;
[0027] FIG. 17 is a top plan view of a central portion of the
stoneblower with portions removed showing the workheads and the
associated actuating assemblies; and
[0028] FIG. 18 is a perspective view of a workhead an actuating
assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] A stoneblower incorporating the present invention is shown
in FIG. 1 and generally designated 10. The stoneblower generally
includes a superstructure 12, trucks 14a-b for rollingly supporting
the superstructure on a railroad track, a jackbeam 16 for lifting
the track and attached ties, a supply of ballast stones 18 carried
in a stone hopper 20, and a plurality of workheads 22 for
delivering the ballast stones 18 under the lifted tie. Generally,
stoneblowers and their operation are known to those skilled in the
art. Therefore, only a brief description of the stoneblower's
operation is provided. The stoneblower 10 of the present invention
is specially adapted to perform maintenance on switches and other
complex rail arrangements. In operation, the stoneblower 10 travels
along the track to a location that requires maintenance. These
locations are by typically determined using any of a variety of
well-known rail profiling techniques. The measured track profile is
used to calculate which ties require additional ballast and how
much ballast should be supplied. A suitable track profile measuring
system carried by the stoneblower is disclosed in U.S. Pat. No.
5,605,099 entitled MAINTENANCE VEHICLE AND METHOD FOR MEASURING AND
MAINTAINING THE LEVEL OF A RAILROAD TRACK and U.S. Pat. No.
5,167,639 entitled RAILROAD MAINTENANCE VEHICLE REFERENCE SYSTEM
TRANSDUCER, which are incorporated herein by reference. Once the
stoneblower 10 reaches a tie where additional stone is required,
the jackbeam 16 is used to lift the rail and attached ties. The
workheads 22 then force blowing tubes into the ballast adjacent the
raised track ties. Stone is blown into the void beneath the raised
ties in the appropriate quantity to level the ties. The workhead
withdraws the blowing tubes, the track is lowered, and the
stoneblower moves down the track to the next location. If desired,
the workheads 22 can be repositioned to supply ballast stone to
additional locations along the tie before the track is lowered and
the stoneblower moves down the track.
[0030] As noted above, the stoneblower 10 includes a superstructure
12 mounted upon front and rear trucks 14a-b. The trucks 14a-b are
generally conventional and will not be described in detail. Suffice
it to say that the trucks 14a-b are adapted to travel along the
railroad track and include at least one pair of drive wheels that
are operatively connected to the main engine 32 to provide the
stoneblower 10 with motion. The superstructure 12 is carried by the
trucks 14a-b and includes an operator compartment 26, a workhead
section 28, and an engine compartment 30. Conventional controls
(not shown) for driving the stoneblower 10 along the track are
located at the front of the operator compartment 26. Controls for
operating the jackbeam 16 and workheads 22 are located at the rear
of the operator compartment overlooking the workhead section 28 of
the stoneblower 10. These controls are described in more detail
below. The workhead section 28 is located directly behind the
operator compartment 26. The workheads 22 and jackbeam 16 are
mounted to the superstructure 12 in the workhead section 28, where
their operation is visible from the location of their controls in
the operator compartment 26. The engine compartment 30 is located
immediately behind the workhead section 28. The main engine 32, air
compressor 34, battery box 36, hydraulic mechanisms 38, fuel tank
40 and other components are located in the engine compartment 30.
The superstructure 12 includes a framework of support beams,
including left and right lower support beams 42a-b that extend
longitudinally along opposite sides of the operator compartment 26,
left and right intermediate support beams 44a-b that extend
longitudinally along opposite sides of the workhead section 28 and
left and right upper support beams 46a-b that extend longitudinally
along opposite sides of the workhead section 28 and the majority of
the engine compartment 30. The lower support beams 42a-b,
intermediate support beams 44a-b and upper support beams 46a-b are
interconnected by a plurality of vertical support beams 48. A
plurality of lateral support beams 50 interconnect the left and
right support beams 42a-b, 44a-b and 46a-b. A pair of workhead
support beams 62a-b extend longitudinally between the lateral
support beams 50. As described in more detail below, the workheads
22a-d are pivotally mounted to the workhead support beams 62a-b.
The described superstructure 12 is merely exemplary, and its design
and configuration may vary from application to application.
[0031] The stoneblower 10 preferably includes four workheads 22a-d,
arranged in left and right pairs. Each pair including a forward
workhead 22a and 22c with a single blowing tube opening rearwardly
and a rear workhead 22b and 22d with a single blowing tube opening
forwardly. The workheads 22a-d are positioned on opposite sides of
a tie T to blow stone under the tie from opposite directions. A
single workhead 22 is illustrated in FIG. 18. The workhead 22
includes a vertical cylinder 54 mounted within a rectangular sleeve
56 (See FIGS. 5-7). The sleeve 56 is mounted to the superstructure
12 by a universal joint 58 that permits the workhead 22 to pivot
both laterally and longitudinally. The universal joint 58 includes
a mounting rod 58 fixedly secured to the upper end of the sleeve
56. A clevis 60 is pivotally mounted on the rod 58 using
conventional bearings or bushings (not shown). The clevis 60 is in
turn pivotally mounted to the corresponding workhead support beam
62a or 62b extending between lateral support beams 64 and 65, again
using conventional bearings or bushings (not shown). The vertical
cylinder 54 is pivotally mounted within the rectangular sleeve 56
(See FIGS. 8-11). The upper end of the vertical cylinder 54 is
pivotally mounted to the approximate center of the sleeve 56 on
axle 66. The axle 66 is rotatably received within fittings 68a-b
that house appropriate bearings or bushings (not shown). This
provides the vertical cylinder 54 with a limited range of forward
and rearward pivotal motion, which as described below is used in
sensing the location of a tie. A pair of resilient couplings 70
interconnect the vertical cylinder 54 and the sleeve 56 just inside
the bottom of sleeve 56 to bias the vertical cylinder 54 in a home
position within the sleeve 56. The couplings 70 are preferably
secured to the vertical cylinder 54 by collar 124. As perhaps best
shown in FIG. 6, the home position H is preferably offset 1.degree.
from the vertical axis V of the rectangular sleeve 56 toward the
direction of the blowing tube opening. As described in more detail
below, this 1.degree. "pre-tilt" permits the vertical cylinder and
rectangular sleeve 56 to come into vertical alignment once the
vertical cylinder tilts 1.degree. upon engagement with a tie face.
The couplings 70 are preferably manufactured from rubber or other
similarly flexible and resilient materials. A transducer 72 or
other similar sensing device is mounted to the vertical cylinder 54
and sleeve 56 to sense pivotal movement of the vertical cylinder 54
with respect to the sleeve 56. The lower end of the vertical
cylinder 54 protrudes from the sleeve 56 to receive a blowing tube
holder 74.
[0032] The vertical cylinder 54 is extended and retracted using
conventional hydraulics. Referring now to FIGS. 8-11, the vertical
cylinder 54 includes rod 100 slidably fitted within cylinder wall
102. The cylinder wall 102 includes a closed end 103 and an open
end 105. A ring 108 and ring seal 109 are fitted within the open
end 105 to close the cylinder wall 102. A pair of conventional
fittings 104 and 106 are mounted in opposite ends of the cylinder
wall 102 to supply and exhaust hydraulic fluid in a conventional
manner. A piston 110 is secured to the inner end of the rod 100 to
divide the interior of the cylinder wall 102 into two distinct
voids. A stop tube 111 is fitted over the rod 100 adjacent the
piston 110. The stop tube 111 engages the inner surface of the ring
seal 108 to limit the stroke of the rod 100. A conventional
transducer 112 is mounted through the closed end 104 of the
cylinder wall 102. The transducer 112 includes a shaft 114 that
extends into a concentric bore 116 defined in the center of rod 100
and a ring 118 that is mounted to the rod 100 around shaft 114. The
transducer 112 provides accurate measurement of the position of the
rod 100 within the cylinder wall 102, and consequently of the
vertical position of the blowing tube 82. A collar 120 is attached
to the lower end of the rod 100 outside of the cylinder wall 102. A
guide rod 122 is rigidly affixed to the collar 120. A second collar
124 is mounted to the cylinder wall 102. The second collar 124
defines a guideway 126 that slidably receives the guide rod 122.
Cooperatively, these components prevent the rod 100 from rotating
within the cylinder wall 102.
[0033] The workhead 22 includes a latch assembly 94 for securing
the blowing tube 82 in the raised position during travel (See FIG.
4). The latch assembly 94 includes a hook 130 that is pivotally
secured to the rectangular sleeve 56 and a conventional hydraulic
cylinder 132 for controlling movement of the hook 130. The latch
assembly 94 further includes a catch 134 defined in collar 120. In
operation, cylinder 132 can be extended to cause hook 130 to engage
catch 134, thereby locking the blowing tube 82 in the raised
position (See solid lines in FIG. 4) or retracted to disengage the
hook 130 permitting extension of the vertical cylinder 54 (See
phantom lines in FIG. 4).
[0034] In general, the blowing tube holder 74 is a vertically
elongated tube having a top 138, a bottom 140 and a neck 142
protruding at an angle to the centerline of the blowing holder 74.
The top 138 defines a mounting bore 76 that is fitted over and
secured to the lower end of the sleeve 56. The bottom 140 includes
a flange 80 adapted to mount a blowing tube 82 as described below.
The neck 142 defines a stone inlet 78 to receive ballast stone and
an air inlet 79 to receive pressurized air. A stone passageway 84
extends from the stone inlet 78 through the flange 80 to feed
ballast stone to the blowing tube 82. An air passageway 83 extends
from the air inlet 79 to the stone passageway 84. The pressurized
air flows through the stone passageway 84 creating a partial vacuum
that draws in stone and expels it through the blowing tube 82.
[0035] The blowing tube 82 is generally conventional and includes a
vertically elongated tube having an inlet opening 86 formed in its
upper end and a vertically extended exit opening 88 formed in the
lower end. The lower tip 90 of the blowing tube is pointed and
wedge shaped to facilitate penetration into the track ballast and
to urge the blowing tube toward the tie face as the blowing tube is
moved downwardly. A flange 92 extends around the blowing tube 82 to
engage flange 80. The blowing tube 82 is secured to the blowing
tube holder 52 by fasteners extending through flanges 92 and
80.
[0036] A flexible supply hose 148 is fitted over neck 142. The
supply hose 148 is generally conventional and is preferably
manufactured from readily available wire reinforced,
abrasion-resistant plastic tubing. The supply hose 148 preferably
includes an internal diameter of approximately three inches, or 75
mm, and is secured to the neck 142 by a conventional clamp (not
shown). As described below, the supply hose 148 receives ballast
stone from the stone metering device in a conventional manner. The
stone and air are supplied to the blowing tube 82 through the
blowing tube holder 52.
[0037] As noted above, the rectangular sleeve 56, and consequently
the entire workhead 22a-d, is pivotally mounted for both
longitudinal and lateral movement. The position of each workhead
22a-d is individually controlled by a separate actuating assembly
150 that is mounted to a lateral support tube 159. Referring now to
FIGS. 15-18, the actuating assembly 150 includes a lateral
adjustment assembly 152 and a longitudinal adjustment assembly 154.
The lateral adjustment assembly 152 controls lateral or transverse
pivotal movement of the workhead 22, and includes a sleeve 156
slidably fitted over the lateral support tube 159 and a lateral
cylinder 158 for moving the sleeve 156 along tube 159. Bushings
172, bearings or other conventional friction reducing elements are
fitted within the sleeve 156 to ease movement of the sleeve 156
along the tube 159. The lateral cylinder 158 is preferably a
conventional hydraulic cylinder. The first end of the cylinder 158
is fixed to the lateral support tube 158 at ear 160 and the second
end is fixed to the sleeve 156 at mounting ear 162. Both ends of
the lateral cylinder 158 are attached using conventional spherical
bushings to allow for slight pivotal movement of the sleeve 156
about the lateral support tube 158. A conventional linear
transducer (not shown) is fitted within the lateral cylinder 158 to
sense the lateral position of the workhead 22.
[0038] The longitudinal adjustment assembly 154 controls fore and
aft pivotal movement of workhead 22, and includes a longitudinal
cylinder 164 secured to the sleeve 156. Referring now to FIGS.
12-14, the longitudinal cylinder 164 extends perpendicularly from
the sleeve 156 and includes a cylinder wall 166, a piston 168
seated within the cylinder wall 166 and an extendible rod 171
interconnected with the piston 168. The cylinder wall 166 includes
a closed end 176 and an open end 178. A ring 180 and ring seal 182
are fitted within the open end 178 to close the cylinder wall 166.
The ring 180 includes an extended stop 186 that limits the stroke
of the piston 168. The ring 180 further includes external threads
184 that engage internal threads 186 on the inner surface of the
cylinder wall 166 to secure the ring 180 is place. A pair of
conventional fittings 188a-b are mounted at the open end 178 of the
cylinder wall 166 to supply and exhaust hydraulic fluid. A second
pair of conventional fittings 190a-b are defined in the sleeve 156.
Passageways 192a-b extend between fittings 190a-b and the closed
end 176 of the cylinder wall 166 to supply and exhaust hydraulic
fluid. The longitudinal cylinder includes two sets of fittings
188a-b, 190a-b so that at least one set of fittings (e.g. 188a and
190a) is readily accessible when the cylinder is installed on
either the left or right side of the vehicle. The other set of
fittings (e.g. 188b and 190b) is plugged when not in use. The
piston 168 is generally conventional and is attached to the rod 170
in a conventional manner, such as by nut 194. The rod 170 protrudes
from the cylinder wall 166 and includes a mounting clevis 168
affixed to its outer end 196. Conventional roller bearings 200 are
fitted within the clevis 168. The clevis 168 is mounted to the
rectangular sleeve 56 of the workhead 22 at ear 170 in a
conventional manner, such as by pin. A pair of support plates
202a-b are mounted between the lateral sleeve 156 and the cylinder
wall 166 to provide lateral strength to the assembly. A
conventional transducer (not shown) is mounted external to the
longitudinal cylinder 164 to sense the longitudinal position of the
workhead 22.
[0039] The workheads 22a-d are controlled by a computerized control
system (not shown). The controls include separate joystick controls
(not shown) for the left pair of workheads 22a-b and the right pair
of workheads 22c-d. The joysticks control the left/right and
fore/aft movement of the workhead. Each joystick includes a
workhead selector switch (not shown) that is moveable between a
first position in which the joystick controls movement of the
forward workhead and a second position in which the joystick
controls movement of the rear workhead. One of the two joysticks
may also be used to operate the jackbeam in a conventional manner
by activating a jackbeam selector switch. Alternatively, a separate
joystick can be provided for operating the jackbeam.
[0040] The control system also includes an automated height control
system (not shown) for controlling the height of the blowing tubes
82. The automated height control system includes a uniform height
control system (not shown) for positioning the blowing tubes 82 at
a uniform height (e.g. in the same horizontal plane) despite the
lateral disposition of the workheads 22a-d. Because the workheads
22a-d are mounted for pivotal movement, each blowing tube 82
inherently travels through an arc as it pivots left/right.
Accordingly, the real height of the blowing tubes 82 for any given
position of the vertical cylinder 54 would normally vary depending
on the position of the workhead 22a-d in this arc. This would
complicate operation of the stoneblower because, in order to
position the blowing tube 82 at a uniform height, it would require
variation in the position of the vertical cylinder 54 for any
variation in the lateral position of the workhead. For example,
FIG. 4 shows the blowing tube 82' in phantom lines at four
different pivotal positions, A, B, C, and D with the vertical
cylinder 54 at a given position. As can be seen, the height of the
blowing tube 82' varies significantly from horizontal line L
between the different positions A, B, C, and D. To address this
problem, the automated height control system (not shown)
automatically adjusts the vertical cylinder 54 to compensate for
variations in the left/right position of the workhead 22. In the
preferred embodiment, the necessary variation in the position of
the vertical cylinder 54 is computed by the formula:
E=.vertline.(D/COS .theta.)-D.vertline., where E is the additional
amount of extension necessary to compensate for the lateral
position of the workhead, D is the vertical distance from the pivot
point of the workhead to the bottom of the tie T, and .theta. is
the angle of the workhead away from its vertical center. The
vertical position of the raised tie T is measured in a conventional
manner by the stoneblower reference system. Because the ties have a
uniform height, the location of the bottom of the tie is easily
computed from the measured value. The value of .theta. is
determined by the transducer (not shown) of the lateral cylinder
158. In operation, the workhead 22a-d will be positioned so that a
point 40 millimeters from the bottom of the blowing tube exit
opening 88 along its vertical centerline is aligned with the bottom
of the tie T. The value of 40 millimeters is used in the preferred
embodiment in part because it provides adequate stone flow. This
value may, however, vary from application to application.
Accordingly, the uniform height control system varies the position
of the vertical cylinder 54 so that a point along the vertical
centerline of the blowing tube 40 mm above the bottom of the exit
opening 88 aligns with the bottom surface of the tie T at all
left/right pivotal locations of the workhead 22a-d. The automated
height control system may be configured to compensate for fore/aft
movement as well as left/right movement of the workhead in a
similar manner, for example, by also extending and retracting the
vertical cylinder in response to fore/aft movement of the
workhead.
[0041] Referring now to FIGS. 1-3, the stoneblower 10 includes a
stone supply system 200 for supplying stone to the workheads 22a-d.
In the preferred embodiment, the stone supply system 200 includes a
stone hopper 20 and four metering augers 204a-d. The stone hopper
20 stores a supply of ballast stones 18 and includes four outlets
206a-d--one communicating with each of the four stone metering
augers 204a-d, respectively. The stone hopper 20 feeds stone into
the stone metering augers 204a-d through outlets 206a-d by gravity.
The stone metering augers 204a-d are generally conventional and
function to supply ballast stone to the workheads 22a-d,
respectively. Each stone metering auger 206a-d includes a casing
208a-d having an inlet (not shown) positioned directly below the
corresponding stone hopper outlet 206a-d and an outlet (not shown)
at the opposite end of the casing 208a-d through which metered
stone flows into the supply hose 148. A screw 210 is rotatably
supported within the casing 208a-d of each stone metering auger
206a-d to both meter the stone and move it from the inlet to the
outlet (See FIG. 3). From the outlet, the stone falls into the
supply hose 148 where it is drawn by gravity and air entrainment
into the blowing tubes 82. The described stone supply system 200 is
merely exemplary and may be replaced by virtually any system
capable of supplying metered stone to the workhead. For example,
the stone metering augers 204a-d can be replaced by other
conventional stone metering devices and the stone hopper 20 can be
replaced by other conventional ballast stone storage devices.
Operation
[0042] For simplicity and clarity, the operation of the present
invention is described in connection with the operation of a single
workhead during maintenance of a switch. It should be readily
apparent that the operation may be extended to virtually any number
of workheads.
[0043] The stoneblower is particularly well suited for use in
maintaining switches and other complex track configurations. As
noted above, the profile of the track is measured using any of a
variety of well-known rail profiling techniques. From the profile,
the ties requiring maintenance are identified and the volume of
ballast stone to be blown beneath each of those ties is computed.
The stoneblower is then manually moved over the rails to the
appropriate location to perform maintenance on the first tie
requiring maintenance. After the stoneblower has traveled to the
location requiring maintenance and prior to positioning of the
workhead, the latch assembly 94 must be moved into the unlocked
position (See phantom lines in FIG. 4). The latch assembly 94 is
operated by conventional controls, such as a toggle switch (not
shown) located near the joystick controls. The latch assembly 94
preferably remains unlocked while the stoneblower performs
maintenance on and indexes through the section of track requiring
maintenance. The latch assembly 94 is locked again after
maintenance is stopped and the stoneblower is ready to travel.
[0044] Once the stoneblower is properly positioned along the track,
the rails and attached ties are lifted using the jackbeam 16. The
jackbeam 16 is preferably operated using a generally conventional
joystick (not shown). The jackbeam 16 may share a joystick with one
of the workhead pairs, as noted above. The jackbeam 16 is manually
positioned adjacent to the rails using the joystick in a
conventional manner. Once positioned, the user depresses the
jackbeam cycle button (not shown) and the jackbeam control system
automatically clamps and lifts the rails in a conventional manner
to the height desired to perform maintenance.
[0045] Once the rails and ties are lifted, the workheads 22a-d are
moved into position to blow the appropriate volume of ballast stone
beneath the raised ties. The workheads 22a-d are positioned using
generally conventional joysticks (not shown), and can be moved into
position in any order. Depending on the track profile, it may not
be necessary to use all of the workheads 22a-d at a given location.
For example, if the right side of the tie has settled while the
left side has maintained the desired height, it may only be
necessary to supply stone under the right side of that tie.
Consequently, it may only be necessary to position and supply stone
through the right workheads 22c-d. Movement of the joystick sends
control signals to the computerized control system. The control
system interprets the signals and either extends or retracts the
appropriate cylinder or cylinders. For example, with the rear
workheads 22b and 22d, rearward movement of the joystick results in
retraction of the corresponding longitudinal cylinder and hence
rearward movement of the workhead 22b and 22d. Similarly, with the
left pair of workheads 22a-b, leftward movement of the joystick
results in extension of the corresponding lateral cylinder and
hence leftward movement of the workheads 22a-b. With the right pair
of workheads 22c-d, leftward movement of the joystick results in
retraction of the corresponding lateral cylinder and hence leftward
movement of the workheads 22a-b.
[0046] In operation, the joystick is manipulated to manually move
the workhead 22a-d into a position adjacent the tie T where
maintenance is to be performed. The blowing tube 82 is positioned
at the desired lateral position a small distance from the face of
the tie T. Once the workhead 22a-d is properly positioned, the user
depresses the workhead cycle button (not shown) to activate the
control system. Upon depression of the workhead cycle button, the
control system automatically moves the blowing tube 82 into
engagement with the tie face and then thrusts it down into the
ballast to the desired height. More specifically, the control
system first swings the workhead 22a-d toward the tie by extending
or retracting the longitudinal cylinder 164 until it determines
that the blowing tube 82 has engaged the tie face. As noted above,
the vertical cylinder is provided with a 1.degree. pre-tilt which
permits the vertical cylinder to pivot 1.degree. with respect to
the rectangular sleeve 56 upon contact with a tie face during
positioning. This 1.degree. pivot is used as a key to indicate that
a tie has been located. In operation, the workhead 22a-d travels
freely until it engages the face of the tie T. Continued movement
of the workhead 22a-d toward the tie causes the vertical cylinder
54 to pivot with respect to the rectangular sleeve 56. The
longitudinal transducer (not shown) senses relative movement
between the vertical cylinder 54 and the sleeve 56 and provides
corresponding signals to the computer control system. Once these
signals indicate that the vertical cylinder 54 has pivoted
1.degree. with respect to the sleeve 56, the computer control
system stops movement of the workhead 22a-d toward the tie and then
lowers the blowing tube into the ballast to the desired height.
[0047] As noted above, the vertical position, or height, of the
workhead 22a-d is controlled by the automated control system. The
control system extends or retracts the vertical cylinder 54 to
position the blowing tube at the desired height. Experience has
revealed that it is desirable to position the blowing tubes 82 so
that the area of the exit opening 88 positioned below the tie is
consistent. This reduces the likelihood of clogging and facilitates
proper stone metering. As noted above, the vertical cylinder 54 is
preferably positioned so that a point along the vertical centerline
of the blowing tube 40 mm above the bottom of the exit opening 88
is aligned with the bottom surface of the tie T. This distance may,
however, vary from application to application. The desired depth of
the blowing tubes will be input into the control system, typically
prior to maintenance. The uniform height control system (not shown)
facilitates uniform vertical positioning of the blowing tubes 82 by
automatically adjusting the height of the blowing tube 82 to
compensate for left/right movement of the workhead. After
depression of the workhead cycle button, the control system
determines the lateral position of the workhead by way of the
linear transducer (not shown) of the lateral cylinder 158. The
uniform height control system then computes any variation in the
position of the vertical cylinder 54 necessary to compensate for
the lateral position of the workhead 22a-d. As noted above, the
vertical position of the raised tie T is measured by the
stoneblower reference system (not shown) and serves as a reference
point for use in computing any necessary variation in the position
of the vertical cylinder 54. Once this value is computed, the
uniform height control system automatically extends the vertical
cylinder 54 the computed amount, thereby driving the blowing tube
82 down into the ballast to the desired vertical position. In the
preferred embodiment, the uniform height control system does not
compensate for fore and aft movement of the workhead, but that
capability may be added as desired. After the workhead(s) 22a-d is
properly positioned, the stone supply system 200 is operated to
supply the desired volume of stone to the workhead(s) 22a-d. The
volume of stone supplied to each workhead 22a-d is preferably
dictated by automated control. The control system (not shown) uses
the information collected from the measured track profile to
determine the appropriate amount of stone for each workhead 22a-d.
The control system (not shown) supplies the appropriate volume of
stone to a given workhead 22a-d by operating the stone metering
device for that workhead 22a-d (e.g. the stone metering auger
204a-d) at a specified supply rate for a specified period of
time.
[0048] Once the desired volume of stone has been blown beneath the
tie, the control system automatically stops the stone supply system
200 and raises the workheads 22a-d into a home position by
retracting the vertical cylinder 54. The home position is high
enough for the blowing tubes 82 to clear the ties as the
stoneblower moves along the track. The jackbeam 16 then lowers the
track, and the stoneblower 10 is ready to move, or index, along the
track to the next location requiring maintenance. This cycle is
typically repeated for the entire length of track requiring
maintenance. Once maintenance is complete or it is otherwise
necessary for the stoneblower to travel from the section of track
being maintained, the workheads 22a-d are fully raised and the
latch assembly 94 for each is locked.
[0049] The stoneblower 10 is also well suited for maintaining plain
line track. When operating on plain line track, the stoneblower's
movement along the track is largely automated and operates under
computer control. The superstructure 12 moves along the track by
indexing movement with respect to the ties. At each indexed
location, the workheads 22a-d are moved into the appropriate
location to perform maintenance manually.
[0050] The computer control directs movement of the stoneblower
based on track profile data provided by the track measuring system.
As noted above, the track profile data is collected prior to and/or
during the maintenance pass of the stoneblower. The computer
control processes the track profile data to determine which ties
require maintenance. As the stoneblower moves along the track, the
computer control stops the stoneblower at the appropriate ties to
perform maintenance. First, the jackbeam 16 is used to lift the
rail and attached ties. The jackbeam 16 operates in generally the
same manner as described above. After the rail is lifted, the
appropriate workhead or workheads 22a-d are positioned in generally
the same manner as described above to supply stone to the desired
location under the lifted tie. As described above, the 1.degree.
pre-tilt of the vertical cylinder is used to position workhead
22a-d with respect to the face of the tie. Once properly
positioned, the stone supply system 200 supplies the desired volume
of stone. After the appropriate volume of stone has been supplied,
the workheads 22a-d are raised into the home position and the track
is lowered. The stoneblower 10 is then ready to move along the
track to the next location requiring maintenance. The above
description is that of a preferred embodiment of the invention.
Various alterations and changes can be made without departing from
the spirit and broader aspects of the invention as defined in the
appended claims, which are to be interpreted in accordance with the
principles of patent law including the doctrine of equivalents. Any
reference to claim elements in the singular, for example, using the
articles "a," "an," "the" or "said," is not to be construed as
limiting the element to the singular.
* * * * *