U.S. patent application number 12/844996 was filed with the patent office on 2012-02-02 for pavement degradation system with a diesel electric drum.
Invention is credited to David R. Hall.
Application Number | 20120027514 12/844996 |
Document ID | / |
Family ID | 45526892 |
Filed Date | 2012-02-02 |
United States Patent
Application |
20120027514 |
Kind Code |
A1 |
Hall; David R. |
February 2, 2012 |
Pavement Degradation System with a Diesel Electric Drum
Abstract
In one aspect of the present invention, a pavement degradation
machine comprises a motor vehicle comprising a combustion engine
connected to an electrical generator, a pavement degradation
assembly comprising a plurality of cutting elements, the pavement
degradation assembly being in mechanical communication with the
electric motor, wherein the generator is in electrical
communication with the electric motor.
Inventors: |
Hall; David R.; (Provo,
UT) |
Family ID: |
45526892 |
Appl. No.: |
12/844996 |
Filed: |
July 28, 2010 |
Current U.S.
Class: |
404/91 ;
404/90 |
Current CPC
Class: |
E01C 23/065 20130101;
E01C 23/088 20130101 |
Class at
Publication: |
404/91 ;
404/90 |
International
Class: |
E01C 23/12 20060101
E01C023/12; E01C 23/08 20060101 E01C023/08 |
Claims
1. A pavement degradation machine, comprising; a motor vehicle,
comprising a combustion engine connected to an electrical
generator; a pavement degradation assembly comprising a plurality
of cutting elements, the pavement degradation assembly being in
mechanical communication with an electric motor; wherein the
generator is in electrical communication with the electric
motor.
2. The pavement degradation machine of claim 1, wherein the
combustion engine comprises a compression-ignition internal
combustion engine.
3. The pavement degradation machine of claim 1, wherein the
combustion engine comprises a spark-ignition internal combustion
engine.
4. The pavement degradation machine of claim 1, wherein the
combustion engine comprises a homogeneous charge compression
ignition engine.
5. The pavement degradation machine of claim 1, wherein the
combustion engine comprises a turbine engine.
6. The pavement degradation machine of claim 1, wherein the
pavement degradation assembly is connected to a frame attached to
the motor vehicle by an articulated coupling.
7. The pavement degradation machine of claim 6, wherein the frame
comprises geometric strut frame members.
8. The pavement degradation machine of claim 6, wherein the frame
comprises traction motors in electrical communication with the
electrical generator.
9. The pavement degradation machine of claim 8, wherein the
traction motors are connected to treads.
10. The pavement degradation machine of claim 8, wherein the
traction motors are connected to wheels.
11. The pavement degradation machine of claim 6, wherein the
pavement degradation assembly comprises one or more cylindrical
drums.
12. The pavement degradation machine of claim 1, wherein the
plurality of cutting elements comprises polycrystalline diamond
inserts.
13. The pavement degradation machine of claim 1, wherein the
electric motor is disposed inside the pavement degradation
assembly.
14. The pavement degradation machine of claim 1, wherein the
electric motor is connected to a hydraulic pump.
15. The pavement degradation machine of claim 14, wherein the
hydraulic pump is connected to one or more hydraulic motors.
16. The pavement degradation machine of claim 1, wherein the
generator provides motive power to the motor vehicle.
17. The pavement degradation machine of claim 1, wherein the
electrical communication between the motor and generator comprises
power and data.
18. The pavement degradation machine of claim 1, wherein the
pavement degradation assembly comprises a debris removal
conveyor.
19. The pavement degradation machine of claim 18, wherein the
debris removal conveyor is in communication with an asphalt
recycling machine.
20. The pavement degradation machine of claim 19, wherein the
debris removal conveyor and the asphalt recycling machine are in
communication with the generator.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to pavement and asphalt maintenance
equipment. Such equipment can be large, heavy, and difficult to
transport. Additionally, these machines may require large amounts
of energy to function and may emit many harmful pollutants into the
atmosphere. It is desirable to provide improved pavement milling
machines that comprise lighter weight, higher efficiency, and
easier transport, while maintaining or increasing productivity.
Efforts to improve pavement milling equipment are disclosed in the
prior art.
[0002] U.S. Pat. No. 6,227,620 to Page discloses a compact, easily
transportable, surface preparation or road mill apparatus which
includes a road mill housing or surface treatment unit having a
cutter drum powered by its own power source. The apparatus also
includes a mounting device for attachment of a working machine,
such as the road mill housing, to a land vehicle having a lifting
mechanism, preferably of the type provided on "front-end loaders".
The surface treatment unit or road mill housing preferably has an
opening for receiving a cylindrical shaft and the mounting device
includes an attachment device for attachment to a land vehicle and
an interconnected cylindrical shaft upon which the road mill
housing can be secured once the shaft is received within the shaft
receiving opening.
[0003] U.S. Pat. No. 7,144,087 to Haroldson discloses systems and
methods for milling paving material. A self-powered milling system
includes a cutting head to mill the paving material. The cutting
head is powered by a milling system motor that speeds up production
and enables the milling of very thick asphalt in a single pass. A
milling system carriage follows the contour of the ground, provides
stability during the milling process, is selectively adjusted to
provide cuts at various angles, and enables precise edge milling. A
breaker bar holds the paving material down as it tries to lift up
during the milling process, and is employed to assist in the
breaking up of the milled aggregate.
[0004] U.S. Pat. No. 4,704,045 to Taylor discloses an apparatus and
method for pulverizing asphalt on roadways and similar
applications. The asphalt is pulverized by a rotating drum with
removable cutting tips which engage a soften underside of the
roadway prior to engaging a harder more compact top surface of the
roadway. The apparatus designed for receiving and rotating various
widths of drums and adaptable for moving the drum along the width
of a mobile piece of equipment supporting the apparatus and
adjacent a curb and gutter of a roadway.
BRIEF SUMMARY OF THE INVENTION
[0005] In one aspect of the present invention, a pavement
degradation machine comprises a motor vehicle with a combustion
engine connected to an electrical generator, a pavement degradation
assembly with a plurality of cutting elements, the pavement
degradation assembly being in communication with an electric motor.
The electrical generator is in communication with the electric
motor. The combustion engine may comprise an internal combustion
engine with spark ignition, compression ignition, homogeneous
charge compression ignition, or may comprise a turbine engine. The
pavement degradation assembly may be attached to a frame connected
to the motor vehicle by an articulated coupling. The frame may
comprise geometric strut frame members. The frame may also comprise
traction motors in communication with the electrical generator. The
traction motors may power treads or wheels. The pavement
degradation assembly may comprise a cylindrical drum. In some
embodiments, the cutting elements may comprise polycrystalline
diamond.
[0006] The electric motor may be disposed inside the cylindrical
drum. In some embodiments, the electric motor may be connected to a
hydraulic pump. The hydraulic pump may be connected to one or more
hydraulic motors. In some embodiments, the generator may provide
motive power to the motor vehicle. The electrical communication
between the motor and the generator may comprise power and data.
The pavement degradation assembly may comprise a debris removal
conveyor, and the conveyor may be in communication with an asphalt
recycling machine. The debris removal conveyor and the asphalt
recycling machine may be in communication with the electrical
generator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is an orthogonal view of an embodiment of a pavement
milling machine.
[0008] FIG. 2 is an orthogonal view of an embodiment of a motor
vehicle.
[0009] FIG. 3 is an orthogonal view of an embodiment of a pavement
milling assembly.
[0010] FIG. 4 is an orthogonal view of another embodiment of a
pavement milling machine.
[0011] FIG. 5 is a perspective view of an embodiment of a drive
tread.
[0012] FIG. 6a is a cross-sectional view of an embodiment of a
pavement milling drum.
[0013] FIG. 6b is a cross-sectional view of another embodiment of a
pavement milling drum.
[0014] FIG. 6c is a cross-sectional view of another embodiment of a
pavement milling drum.
[0015] FIG. 6d is a cross-sectional view of another embodiment of a
pavement milling drum.
[0016] FIG. 7 is an orthogonal view of another embodiment of a
pavement milling assembly.
[0017] FIG. 8 is an orthogonal view of another embodiment of a
pavement milling machine.
[0018] FIG. 9 is an orthogonal view of another embodiment of a
pavement milling machine.
DETAILED DESCRIPTION OF THE INVENTION AND THE PREFERRED
EMBODIMENT
[0019] Referring now to the figures, FIG. 1 discloses an embodiment
of a pavement milling machine 100. Milling machine 100 comprises a
motor vehicle 101 connected to a pavement degradation assembly 102.
The milling machine 100 traverses a paved roadway 103. The milling
machine may degrade a portion of a paved formation such as a road,
side walk, parking lot, patio, or airport runway. The motor vehicle
101 and the pavement degradation assembly may be connected by an
articulated coupling 104 and an electrical connection 105.
[0020] FIG. 2 discloses another embodiment of a motor vehicle 200.
In this embodiment, the motor vehicle 200 comprises an
industrial-duty truck frame 201 with a passenger compartment 202.
An internal combustion engine 203 may be disposed on a load
carrying portion 204 of the truck frame. The internal combustion
engine may be connected to an electrical generator 205 through a
rotational coupling such as a shaft, sleeve, or clutch. Some
embodiments may comprise a centrifugal clutch, a clutch with
mechanical actuation, hydraulic actuation, or electrical actuation.
A gear set may be disposed intermediate the engine and the
generator to increase or decrease the rotational velocity of the
generator with respect to the engine. The gear set may comprise
straight-cut gears, helical gears, planetary gears, or other gears
and may comprise multiple selectable gear ratios. A constantly
variable transmission may be disposed intermediate the combustion
engine and the electric motor. Varying the speed ratio between the
engine and generator with these devices may allow added flexibility
in electrical output voltage and power from the generator while
maintaining the engine at a rotational speed that provides optimum
efficiency.
[0021] The internal combustion engine 203 may comprise a diesel
fueled compression ignition engine. In some embodiments, this
engine may be fueled with biodiesel, petroleum diesel, vegetable
oil, or combinations thereof. The engine may comprise layouts such
as inline cylinders, V arranged cylinders, or opposed cylinders.
The engine may comprise any number of cylinders, but in a preferred
embodiment, the diesel engine comprises a 6 cylinder inline
arrangement. Other embodiments may comprise more cylinders, such as
in a V-12 arrangement. A greater number of cylinders may reduce
harmonic vibrations in the engine components, reducing wear and
increasing machine lifetime, and reducing fatiguing noise and
vibration experienced by the operator.
[0022] In other embodiments, a gasoline fueled engine may be used.
Gasoline engines may comprise a higher power-to-weight ratio than a
comparable diesel engine. Blends of ethanol, methanol, and other
alternative fuels may be used to reduce petroleum consumption and
minimize adverse environmental impact. Engine configurations as
previously detailed may be used. Some embodiments may comprise
spark ignition as in a traditional Otto-cycle gasoline engine,
while other embodiments may comprise homogeneous charge compression
ignition (HCCI) to improve efficiency and minimize fuel use and
emissions. HCCI engines allow lean burning conditions that allow
improved thermodynamic efficiency. Such conditions would cause
severe damage and excessive oxides of nitrogen emissions in a
conventional spark ignition engine.
[0023] The electrical generator 205 may comprise an AC or DC
generator. In a preferred embodiment, a three-phase AC generator is
used. Preferably, AC power is supplied to the load. In other
embodiments, AC power may be rectified to DC to drive a DC load.
Alternatively, a DC generator may be used to power a DC load. A
power distribution box 207 may comprise one or more power outputs
with connectors that correspond to mating connectors on power
cables attached to tools such as the asphalt milling assembly
disclosed in relation to FIG. 1. The power distribution box may
also comprise load sensitive controls in communication with the
control systems of engine 203. Heavy electrical loads on the
generator may trigger an increase in engine RPM by signaling the
engine controls to inject more fuel into the combustion chambers in
a compression-ignition engine, or by opening the throttle of a
spark ignition engine. The engine controls may also monitor engine
exhaust temperature, coolant temperature, cylinder head
temperature, and oil temperature and adjust engine operating
conditions accordingly by varying fuel flow rate or throttle
position. The power distribution box 207 may also comprise circuit
breakers to interrupt electrical current if safe operating limits
are exceeded. For example, the breaker may interrupt the circuit if
there is an electrical short in a load connected to the
generator.
[0024] In some embodiments, the engine and generator may be
fastened to a pallet or skid 208, allowing easy removal and
replacement of the power generation unit. This may ease servicing,
and allow the power generation unit to be used on multiple
machines. The pallet or skid may comprise lift points for
attachment to an overhead crane or hoist, and may comprise recesses
for placement and removal by forklift. Bolts, clamps, or other
devices may be used to fasten the pallet to the truck frame.
[0025] In some embodiments, the motor vehicle 200 may comprise a
traditional gas or diesel engine drivetrain that provides motive
power to the vehicle. In other embodiments, power from the
electrical generator may be directed to electric motors driving the
wheels of the motor vehicle.
[0026] FIG. 3 discloses an embodiment of a pavement milling
assembly 300. In this embodiment, the pavement milling assembly 300
may be connected to a motor vehicle such as that described in
relation to FIG. 2 by an articulated coupling 301 and an electrical
connection 302. The pavement milling assembly 300 may comprise a
milling drum 303 comprising a plurality of cutting elements 304. In
some embodiments, the cutting elements may comprise polycrystalline
diamond material to inhibit wear and improve the service life of
the cutting elements. In other embodiments, the cutting elements
may comprise cubic boron nitride, tungsten carbide, other hard
materials, or combinations thereof. Materials resistant to abrasion
and heat are preferable to reduce the maintenance requirements by
extending the life of the cutters between necessary replacements.
The pavement milling machine also comprises drive treads 306 in
contact with the road surface.
[0027] In this embodiment, the milling drum may be driven by an
electric motor connected to a generator like that described in
relation to FIG. 2. The electric motor may drive the drum through a
chain drive, a driveshaft, or belt, or the motor shaft may be
directly coupled to the drum. In some embodiments, a single speed
gear reduction or a multiple speed transmission may be disposed
intermediate the motor and drum. The gear reduction or transmission
may comprise straight cut gears, helical gears, planetary gears, or
other gearing configurations. A constantly variable transmission
comprising variable diameter pulleys may be used in some
embodiments. Electric motors may be connected to the drive treads
306 and connected to the electrical generator through electrical
connection 302 to provide motive power to the pavement milling
machine.
[0028] In other embodiments, the pavement milling assembly may
comprise a single electric motor that drives a hydraulic pump. The
hydraulic pump may be connected through a hydraulic control system
to one or more hydraulic motors attached to the drum. Hydraulic
motors may also be disposed on the drive treads 306 to provide
motive power to the pavement milling machine.
[0029] The motor may be connected to the generator by the
electrical connection 302, which may carry electrical power from
the generator to the motor, and it may also carry electrical data,
such as drum rotational speed, vehicle road speed, and drum torque.
Additional information may be communicated between the motor and
generator, and displayed on instruments near an operator in the
motor vehicle or the pavement milling assembly.
[0030] In this embodiment, the pavement milling assembly 300 may
comprise geometric strut frame members 305. These frame members may
comprise carbon fibers, glass fibers, aramid fibers, or other
fibers, and polymer resin to maintain the fibers in a structural
form. Composite geometric struts may provide a higher strength to
weight ratio than other frame rail geometries. In some embodiments,
the frame members may comprise a closed section member, a boxed
section, or C, U or I beam geometry. In these embodiments, the
frame members may comprise steel alloys, aluminum alloys, composite
materials, or other materials.
[0031] FIG. 4 discloses another embodiment of a pavement milling
machine 400. In this embodiment, the pavement milling machine 400
is connected to an pavement recycling machine 401 and a road roller
402. As the pavement milling machine traverses a road surface, the
milling machine degrades the paved surface creating loose debris
that may include cement, asphalt, and aggregate. The debris may be
collected and removed from the road surface by a conveyor 403. The
conveyor may comprise a metal or rubber belt, and be powered by a
hydraulic or electric motor. In some embodiments, the debris may be
delivered to a dump truck or semi truck for removal from worksite.
In this embodiment, the debris is poured into the asphalt recycling
machine 401. The asphalt recycling machine may reconstitute the
debris by adding additional aggregate and bituminous asphalt or
other petroleum or synthetic tar. The recycling machine 401 may
then expel the mixture of aggregate and asphalt back onto the road
bed. A road roller 402 may then compress the mixture to create a
substantially uniform road surface. In this embodiment, the
recycling machine 401 and the road roller 402 may be connected to
the pavement milling machine 400 by articulated couplings 406 and
407. Electrical connections and may also be disposed intermediate
the pavement milling assembly and the recycling machine and road
roller. The electrical connections may be integrated with the
articulated couplings, or may comprise cables. The recycling
machine and road roller may be powered solely by electrical power
from the engine and generator 410 associated with the pavement
milling machine 400. The electrical connectors and may transfer
data as well as power. The data may comprise information such as
road speed, tool speed, tool power requirements, and operating
conditions that may be displayed on instruments visible to an
operator.
[0032] Road speed information from each machine may be input to an
electronic control system, and the control system may substantially
match road speed among the machines to minimize stress on the
articulated couplings and to prevent shocks and traction
losses.
[0033] Arranging the tools in this manner may allow greater
efficiency, as each pavement tool draws power from a single
generator. The engine driving this generator can be tuned for
maximum efficiency at a single operating RPM by adjusting intake
and exhaust tract length and flow area, valve size, lift, and
duration, and other mechanical parameters. Additionally, the
separate tools may provide lighter weight, less maintenance cost,
and easier transport by negating the need for individual engines on
each tool. In some embodiments, some of the equipment may draw
power from the electric generator(s) run by the diesel engine,
while the remaining equipment draws its power from other
sources.
[0034] The train of road construction equipment may include
degradation equipment, transporting equipment, aggregate processing
equipment, and paving equipment. The processing equipment may
include ovens that heat debris recently removed from the road bed
or other aggregate that is supplied and/or mixed with the recently
removed debris. The processing equipment may also mix new aggregate
with the recently removed aggregate.
[0035] The degradation equipment may include the milling drums,
including drums with high pick density for micro-milling the
pavement. Micro-milling may include operating the drum at a faster
rate than traditional drums, but milling at a shallower depth or
translating the milling machine at a slower pace while the drum
rotates at the higher RPM. The micro-milling may produce finer
aggregate that may be recyclable in situ. In some embodiments, a
drum designed for micro-milling may cut at a depth of 1/2 inch or
less. In other embodiments, the milling drum comprises the
traditional pick density and spacing.
[0036] FIG. 5 discloses an embodiment of a pavement milling machine
500 comprising a traction drive tread 501 with an electric traction
motor 502. The electric traction motor may be attached directly to
a drive tread frame 503 and be electrically connected to a power
distribution harness 504. Power for the electric motor may come
from an engine and generator unit disposed on the pavement milling
machine or a connected motor vehicle. Locating the drive motors in
the drive tread frame may minimize the mechanical complexity,
weight, and required maintenance, compared to hydraulic or
mechanical drives. The pavement milling machine may comprise
multiple drive treads. In a preferred embodiment, the pavement
milling machine comprises four drive treads positioned
substantially at the corners of the milling machine frame. Each
drive tread may comprise a traction motor. In some embodiments,
only the front or only the rear drive treads may comprise
motors.
[0037] FIG. 6a discloses another embodiment of a pavement
degradation assembly 600. In this embodiment, the degradation
assembly comprises a plurality of cutting elements 601 disposed on
an outer diameter of a hollow drum 602. An electric motor 603 is
disposed within the drum 602. The electric motor comprises a
driveshaft 604 rotationally fixed to the drum 602. A rigid sleeve
605 fixes the housing of the electric motor 603 to a support 606 of
a milling machine. Electrical connections may connect the motor 603
to an electrical power source, such as an electrical generator.
[0038] FIG. 6b discloses the pavement milling drum associated with
FIG. 6b in an orthogonal cross-sectional view. Drum 602 comprises
bearings 607 and 608. Bearing 607 connects the drum 602 to frame
support 606. A rigid sleeve 605 is disposed in an inner diameter of
bearing 608. Mounting bolts 609 pass through drive side frame
support 610, through rigid sleeve 605, and thread into the housing
of motor 603. Bearings 607 and 608 may comprise ball bearings,
tapered roller bearings, needle bearings, plain bearings, or other
bearing designs. In some embodiments, the bearings may comprise
hydrodynamic bearings with a pressurized lubrication system.
[0039] FIG. 6c discloses another embodiment of a pavement milling
assembly 600. In this embodiment, two electric motors 610 and 611
are disposed within a drum 612. Providing two electric motors may
reduce vibrations from torsional loading of the drum or from weight
imbalance.
[0040] FIG. 6d shows an isometric cross-sectional view of a
pavement degradation assembly comprising two direct-current
electric motors 610 and 611 comprising commutators 613 and 614. In
other embodiments, alternating-current motors may be used.
[0041] FIG. 7 discloses another embodiment of a pavement
degradation assembly 700. In this embodiment, the pavement
degradation assembly may be connected to an engine and generator
through electrical connection 701. An electric motor 702 may be
attached to a frame 703, and may drive a hydraulic pump 704.
Hydraulic pump 704 pressurizes a working fluid, and the working
fluid may be delivered to hydraulic motors through hydraulic lines
705. Hydraulic motors may be disposed adjacent to and driving a
degradation drum 706 and drive treads 707. The hydraulic system may
comprise a control system that limits the motor speed at the drum
and drive track motors.
[0042] FIG. 8 discloses another embodiment of a pavement milling
machine 800. Milling machine 800 comprises a combustion engine 801
connected to an electrical generator 802. Electric motors may be
mechanically connected to a degradation drum 803 and drive tracks
804. The combustion engine and electric generator may be attached
to a pallet or skid 805 that is easily removable from the milling
machine 800 for replacement or repair.
[0043] FIG. 9 discloses another embodiment of a pavement milling
machine 900. In this embodiment, the milling machine comprises a
turbine engine 901 connected to an electrical generator 902.
Milling machine 900 also comprises drive wheels 903. The drive
wheels may be driven by electric motors electronically connected to
the electrical generator 902. Turbine engines may comprise a higher
power-to-weight ratio than piston engines, and may reduce the
difficulty of transporting the milling machine. Additionally, many
turbine engines are able to burn a wide variety of fuels including
gasoline, Diesel fuel, kerosene, biological fuels such as biodiesel
and ethanol, and other mineral and organic fuels.
[0044] Whereas the present invention has been described in
particular relation to the drawings attached hereto, it should be
understood that other and further modifications apart from those
shown or suggested herein, may be made within the scope and spirit
of the present invention.
* * * * *