U.S. patent application number 12/962758 was filed with the patent office on 2011-06-30 for vibratory system for a compactor.
This patent application is currently assigned to Caterpillar Paving Products Inc.. Invention is credited to Eric A. Hansen, John L. Marsolek, Nathan L. Mashek, Nicholas A. Oetken.
Application Number | 20110158745 12/962758 |
Document ID | / |
Family ID | 44187776 |
Filed Date | 2011-06-30 |
United States Patent
Application |
20110158745 |
Kind Code |
A1 |
Oetken; Nicholas A. ; et
al. |
June 30, 2011 |
VIBRATORY SYSTEM FOR A COMPACTOR
Abstract
A vibratory system for a compactor is provided. The vibratory
system has a first eccentric, a second eccentric, and a drive
shaft. The second eccentric is rotatably and coaxially positioned
with respect to the first eccentric. The drive shaft is rotatably
coupled to the second eccentric and rotatably coupled to the first
eccentric through a helical spline.
Inventors: |
Oetken; Nicholas A.;
(Brooklyn Park, MN) ; Mashek; Nathan L.; (St.
Michael, MN) ; Marsolek; John L.; (Watertown, MN)
; Hansen; Eric A.; (Big Lake, MN) |
Assignee: |
Caterpillar Paving Products
Inc.
Minneapolis
MN
|
Family ID: |
44187776 |
Appl. No.: |
12/962758 |
Filed: |
December 8, 2010 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
61291701 |
Dec 31, 2009 |
|
|
|
Current U.S.
Class: |
404/72 ;
404/117 |
Current CPC
Class: |
E01C 19/286
20130101 |
Class at
Publication: |
404/72 ;
404/117 |
International
Class: |
E01C 19/38 20060101
E01C019/38 |
Claims
1. A vibratory system for a compactor, comprising: a first
eccentric; a second eccentric rotatably and coaxially positioned
with respect to the first eccentric; and a key shaft rotatably
coupled to the second eccentric and rotatably coupled to the first
eccentric.
2. The vibratory system of claim 1, wherein the key shaft comprises
an axial spline portion; a helical spline portion, and wherein the
first eccentric is rotatably coupled to the first eccentric through
the helical spline portion.
3. The vibratory system of claim 2, further comprising: an actuator
having an extension and a retraction stroke and coupled to the key
shaft, and wherein the second eccentric rotates in a first angular
direction with respect to the first eccentric on the extension
stroke and rotates in a second angular direction opposite the first
angular direction with respect to the first eccentric on the
retraction stroke.
4. The vibratory system of claim 3, further comprising: an adapter
coupling the actuator to the key shaft, the adapter including at
least one bearing.
5. The vibratory system of claim 2, wherein the second eccentric is
positioned within the first eccentric.
6. The vibratory system of claim 5, wherein the axial portion of
the key shaft slides within the second eccentric.
7. The vibratory system of claim 5, further comprising: an actuator
having an extension and a retraction stroke and coupled to the key
shaft, and wherein the second eccentric rotates in a first angular
direction with respect to the first eccentric on the extension
stroke and rotates in a second angular direction opposite the first
angular direction with respect to the first eccentric on the
retraction stroke, wherein the first and the second eccentric each
have a radial alignment hole, and the axes of the radial alignment
holes align when the first eccentric and the second eccentric are
in phase.
8. The vibratory system of claim 5, further comprising: an actuator
having an extension and a retraction stroke and coupled to the key
shaft, and wherein the second eccentric rotates in a first angular
direction with respect to the first eccentric on the extension
stroke and rotates in a second angular direction opposite the first
angular direction with respect to the first eccentric on the
retraction stroke, wherein the first and the second eccentric each
have a radial alignment hole, and the axes of the radial alignment
holes align when the first eccentric and the second eccentric are
180 degrees out of phase.
9. The vibratory system of claim 2, wherein the first eccentric has
a helical bore and further comprising: a helical screw positioned
in the helical bore and coupled to the key shaft, the helical
spline positioned on the helical screw.
10. The vibratory system of claim 2, further comprising: a motor
coupled to the first eccentric and configured to rotate the first
eccentric about an axis.
11. The vibratory system of claim 2, further comprising: a motor
coupled to the second eccentric and configured to rotate the second
eccentric about an axis.
12. A compactor, comprising: a drum having a drum axis; and a
vibratory system rotatably positioned within the drum about the
drum axis and having: a first eccentric; a second eccentric
rotatably and coaxially positioned with respect to the first
eccentric; and a key shaft rotatably coupled to the second
eccentric and rotatably coupled to the first eccentric through a
helical spline.
13. The compactor of claim 12, wherein the key shaft comprises an
axial spline portion; a helical spline portion; and wherein the
first eccentric is rotatably coupled to the first eccentric through
the helical spline portion.
14. The compactor of claim 13, wherein the vibratory system further
includes: an actuator having an extension and a retraction stroke
and coupled to the key shaft, and wherein the second eccentric
rotates in a first angular direction with respect to the first
eccentric on the extension stroke and the second eccentric rotates
in a second angular direction opposite the first angular direction
with respect to the first eccentric on the retraction stroke.
15. The compactor of claim 12, wherein the vibratory system further
includes: an adapter coupling the actuator to the key shaft, the
adapter including at least one bearing.
16. The compactor of claim 12, wherein the second eccentric is
positioned within the first eccentric.
17. The compactor of claim 16, wherein the axial portion of the key
shaft slides within the second eccentric.
18. The compactor of claim 16, wherein the vibratory system further
includes: an actuator having an extension and a retraction stroke
and coupled to the key shaft, and wherein the second eccentric
rotates in a first angular direction with respect to the first
eccentric on the extension stroke and rotates in a second angular
direction opposite the first angular direction with respect to the
first eccentric on the retraction stroke, and wherein the first and
the second eccentric each have a radial alignment hole, and the
axes of the radial alignment holes align when the first eccentric
and the second eccentric are in phase.
19. The compactor of claim 16, wherein the vibratory system further
includes: an actuator having an extension and a retraction stroke
and coupled to the key shaft, and wherein the second eccentric
rotates in a first angular direction with respect to the first
eccentric on the extension stroke and rotates in a second angular
direction opposite the first angular direction with respect to the
first eccentric on the retraction stroke, and wherein the first and
the second eccentric each have a radial alignment hole, and the
axes of the radial alignment holes align when the first eccentric
and the second eccentric are 180 degrees out of phase.
20. The compactor of claim 13, wherein the first eccentric has a
helical bore and the vibratory system further includes: a helical
screw positioned in the helical bore and coupled to the key shaft,
the helical spline positioned on the helical screw.
21. The compactor of claim 13, wherein the vibratory system further
includes: a motor coupled to the first eccentric and configured to
rotate the first eccentric about the drum axis.
22. The compactor of claim 13, wherein the vibratory system further
includes: a motor coupled to the second eccentric and configured to
rotate the second eccentric about the drum axis.
23. A method for providing a vibratory system for a compactor,
comprising: providing a first eccentric, a second eccentric, and a
key shaft; rotatably and coaxially positioning the second eccentric
with respect to the first eccentric; rotatably coupling the key
shaft to the second eccentric; and rotatably coupling the key shaft
to the first eccentric.
24. The method of claim 23, wherein the key shaft comprises an
axial spline portion; a helical spline portion; and wherein the
step of rotatably coupling the key shaft to the first eccentric is
done through the helical spline portion.
25. The method of claim 23, further comprising: coupling a motor to
the first eccentric, the motor configured to rotate the first
eccentric about an axis; and coupling an actuator to the key shaft,
the actuator having an extension and a retraction stroke, wherein
the second eccentric rotates in a first angular direction with
respect to the first eccentric on the extension stroke and rotates
in a second angular direction opposite the first angular direction
with respect to the first eccentric on the retraction stroke.
26. The method of claim 23, further comprising: coupling a motor to
the second eccentric, the motor configured to rotate the second
eccentric about an axis; and coupling an actuator to the key shaft,
the actuator having an extension and a retraction stroke, wherein
the second eccentric rotates in a first angular direction with
respect to the first eccentric on the extension stroke and rotates
in a second angular direction opposite the first angular direction
with respect to the first eccentric on the retraction stroke.
Description
CLAIM FOR PRIORITY
[0001] The present application claims priority from U.S.
Provisional Application Ser. No. 61/291,701, filed Dec. 31, 2009,
which is fully incorporated herein.
TECHNICAL FIELD
[0002] This disclosure relates to a vibratory system for a
compactor machine, and more particularly, to a variable amplitude
vibratory system for a compactor machine.
BACKGROUND
[0003] Vibratory compactor machines are frequently used to compact
freshly laid asphalt, soil, and other compactable materials. These
compactor machines may include plate type compactors or rotating
drum compactors with one or more drums. The drum-type compactor
compacts the material over which the machine is driven. In order to
compact the material, the drum assembly includes a vibratory
mechanism including inner and outer eccentric weights arranged on a
rotatable shaft within the interior cavity of the drum, for
inducing vibrations on the drum.
[0004] The amplitude and frequency of the vibratory forces
determine the degree of compaction of the material, and the speed
and efficiency of the compaction process. The amplitude of the
vibration forces is changed by altering the position of a pair of
weights with respect to each other. The frequency of the vibration
forces is managed by controlling the speed of a drive motor in the
compactor drum.
[0005] The required amplitude of the vibration force may vary
depending on the characteristics of the material being compacted.
For instance, high amplitude works best on thick lifts or soft
materials, while low amplitude works best on thin lifts and harsh
mixes. Amplitude variation is important because different materials
require different levels of compaction. Moreover, a single
compacting process may require different amplitude levels because
higher amplitude may be required at the beginning of the process,
and the amplitude may be gradually lowered as the process is
completed.
[0006] Conventional vibratory compactor machines are problematic in
that the amplitude and frequency of the vibration force can only be
set to certain predetermined levels, or the mechanisms for
adjusting the vibration amplitude are complex. One such vibratory
mechanism is disclosed in U.S. Pat. No. 4,350,460 issued to Lynn A.
Schmelzer et al. on Sep. 21, 1982 and assigned to the Hyster
Company.
[0007] The present disclosure is directed to overcome one or more
of the problems as set forth above.
SUMMARY
[0008] In one aspect of the present disclosure, a vibratory system
for a compactor is provided. The vibratory system has a first
eccentric, a second eccentric, and a drive shaft. The second
eccentric is rotatably and coaxially positioned with respect to the
first eccentric. The drive shaft is rotatably coupled to the second
eccentric and rotatably coupled to the first eccentric.
[0009] In another aspect of the present disclosure, a compactor is
provided. The compactor has a drum and a vibratory system. The drum
has a drum axis. The vibratory system is rotatably positioned
within the drum about the drum axis and has a first eccentric, a
second eccentric, and a drive shaft. The second eccentric is
rotatably and coaxially positioned with respect to the first
eccentric. The drive shaft is rotatably coupled to the second
eccentric and rotatably coupled to the first eccentric.
[0010] In a third aspect of the present disclosure, a method of
providing a vibratory system for a compactor is provided. The
method includes the step of providing a first eccentric, a second
eccentric, and a drive shaft. The method also includes the steps of
rotatably and coaxially positioning the second eccentric with
respect to the first eccentric, and the step of rotatably coupling
the drive shaft to the second eccentric. The method includes the
step of rotatably coupling the drive shaft to the first
eccentric.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a side elevation view of a machine embodying the
present disclosure;
[0012] FIG. 2 shows an axial cross section view taken along the
line 2-2 through a compacting drum of the machine of FIG. 1,
showing an embodiment of the present disclosure;
[0013] FIG. 3 is a detail view of the vibratory mechanism of FIG.
2, with the eccentric shown at the maximum amplitude position;
and
[0014] FIG. 4 is a detail view of the vibratory mechanism of FIG.
2, with the eccentric shown at the minimum amplitude position.
DETAILED DESCRIPTION
[0015] FIG. 1 illustrates a machine 10 for increasing the density
of a compactable material or mat 12 such as soil, gravel, or
bituminous mixtures. The machine 10 is, for example, a double drum
vibratory compactor, having a front or first compacting drum 14 and
a rear or second compacting drum 16 rotatably mounted on a main
frame 18 about a drum axis 19 (seen in FIG. 2), although compactors
having only a single drum may also be used without departing from
the present disclosure. The main frame 18 also supports an engine
20 that supplies power to at least one power source 22, 24.
Electrical generators or fluid pumps, such as variable displacement
fluid pumps, may be used as interchangeable alternatives for power
sources 22, 24 without departing from the present disclosure.
[0016] As the front drum 14 and the rear drum 16 are structurally
and operatively similar, the description, construction and elements
comprising the front drum 14 will now be discussed in detail and
applies equally to the rear drum 16.
[0017] As seen in FIG. 2, the front drum 14 is shown in a split
drum configuration. Those skilled in the art will recognize that
front drum 14 could also be in a solid drum configuration without
departing from the scope and spirit of this disclosure.
Notwithstanding, front drum 14 includes a split 15 that separates
front drum 14 into a first and a second drum section 30, 32, a
first and a second propel motor 42, 44, a pair of offset gearboxes
46, a support arrangement 50, and a vibratory system 90. Each of
the first and second drum sections 30, 32 is made up of an outer
shell 34 that is manufactured from a steel plate that is rolled and
welded at the joining seam. A first bulkhead 36 is fixedly secured
to the inside diameter of the outer shell 34 of the first drum
section 30 as by welding and a second bulkhead 38 is fixedly
secured to the inside diameter of the outer shell 34 of the second
drum section 32 in the same manner. The first and second drum
sections 30, 32 are vibrationally isolated from the main frame 18
by rubber mounts (not shown).
[0018] The first and the second propel motors 42, 44 are positioned
between the main frame 18 and the first and the second drum
sections 30, 32, respectively. For example, the first and second
propel motors 42, 44 are each connected to a mounting plate (not
shown) secured to the main frame 18 via rubber mounts (not shown).
The output of the first and second propel motors 42, 44 are
connected to the first and the second bulkheads 36, 38,
respectively, through a pair of offset gearboxes 46. The offset
gearboxes 46 allow the first and second propel motors 42, 44 to be
positioned offset from the drum axis 19. With a different mounting
configuration or motor arrangement, the first and second propel
motors may be directly connected to the first and second bulkheads
36, 38, eliminating the offset gearboxes 46. The first and second
propel motors 42, 44 are operatively connected to the power source
22, 24, which supplies a pressurized operation fluid or electrical
current to the first and second propel motors 42, 44 for propelling
the first and second drum section 30, 32.
[0019] The support arrangement 50 rotatably connects the first drum
section 30 to the second drum section 32 and houses a vibratory
mechanism 100 of the vibratory system 90 within a housing 58. The
support arrangement 50 is rotatably connected between the first and
second bulkheads 36, 38 to enable the first and second drum section
30, 32 to rotate in relation to one another. The support
arrangement 50 includes a first support member 52 and a second
support member 54. The first support member 52 is connected to the
first bulkhead 36, while the second support member 54, being made
up of two separate pieces connected by fasteners, is connected to
the second bulkhead 38. Although the second support member 54 as
shown in this embodiment is made of two separate pieces, it may
also be one complete piece. The first support member 52 is
rotatably positioned inside the second support member 54 and
rotatably connected by a bearing arrangement 56. In this case, the
bearing arrangement consists of tapered roller bearings. The
support arrangement 50 allows the first propel motor 42 to rotate
the first drum section 30 about the drum axis 19 at either the same
rate or at a different rate than the second propel motor 44 rotates
the second drum section 32 about the drum axis 19.
[0020] Of course, this is but one of a number of arrangements that
the support arrangement 50 may assume. For example, the second
support member 54 may be rotatably positioned outside the first
support member 52. The first support member 52 may also be
rotatably positioned outside the second support member 54. Another
example may have the first and second support members 52, 54 come
together at the bearing arrangement 56 where they may be rotatably
connected without any overlap of the first and second support
members 52, 54. Additionally, the bearing arrangement 56 that may
be seen in any of the embodiments may comprise, but is not limited
to, tapered roller bearings, ball bearings, and bronze
bushings.
[0021] The vibratory system 90 includes the vibratory mechanism
100, a vibratory motor 110, a drive shaft 118, and a linear
actuator 150. The vibratory mechanism 100 is rotatably supported
about the drum axis 19 within the housing 58 with a plurality of
bearings 170. The bearings 170 may be cylindrical roller bearings,
although other types of bearings or bushings may also be used. In
order to provide lubrication and cooling to the vibratory mechanism
100, the housing 58 may be filled with oil. A lip seal 176 may be
positioned at the ends of the housing 58 to keep the oil within the
housing 58 and dirt and debris out of the housing 58.
[0022] Referring now to FIGS. 3-4, the vibratory mechanism 100 is
driven by the vibratory motor 110 through the drive shaft 118, and
includes an outer eccentric 120, an inner eccentric 130, and a key
shaft 140. The vibratory motor 110 may be a hydraulic or electric
motor and may be mounted to the machine 10 through a mounting plate
(not shown) that is secured to the main frame 18 via rubber mounts
(not shown). Alternately, the vibratory motor 110 may be mounted to
the main frame through some other way known in the art, such as by
mounting the vibratory motor 110 to one of the offset gearboxes 46
through a flange 112. The vibratory motor 110 is rotationally
coupled to the drive shaft 118 through an adapter 114 with a speed
sensor 116. The speed sensor 116 is a tachometer and may include a
toothed ring and pickup, a magnetic sensor, or any other technique
known in the art. The vibratory motor 110 may be driven by one of
the power sources 22, 24, or by another power source (not
shown).
[0023] The outer eccentric 120 is shown as a three-piece assembly
with a drive side stub shaft 121, a helical side stub shaft 122,
and a lobe 126. The drive shaft 118 is attached to the drive side
stub shaft 121 via a splined connection or other technique known in
the art. The bearings 170 may be attached to the outside of stub
shafts 121, 122. The drive side stub shaft 121 and the helical side
stub shaft 122 are attached to the lobe 126 via bolts or some other
known technique. The lobe 126 may formed as a hollow
semi-cylindrical or lobed casting having an axis of rotation and
with more weight on one radial side than on the other. The helical
side stub shaft 122 also includes a helical bore 124, which will be
described in detail below.
[0024] The inner eccentric 130 is positioned within the outer
eccentric 120 and is rotatably supported about the drum axis 19
with a pair of bearings 172, which may be tapered roller bearings,
ball bearings, or bushings such as bronze bushings. Bearings 172
are positioned within the stub shafts 121, 122. The inner eccentric
130 may be a solid semi-cylindrical or lobed casting with more
weight on one radial side than on the other. The inner eccentric
130 also includes a bore 132. The bore 132 is formed with one or
more splines that extend axially parallel to the drum axis 19.
Alternately, the bore 132 may be formed with an axially-extending
keyway (not shown).
[0025] The key shaft 140 has an axial splined portion 142 at one
end, a smooth portion 144 in the middle, and a helical splined
portion 146 at the other end. The axial splined portion 142 engages
with the bore 132 of the inner eccentric 130 such that the inner
eccentric 130 and the key shaft 140 are rotatably fixed with
respect to each other. However, the key shaft 140 may still slide
axially into the bore 132 of the inner eccentric 130. In one
embodiment, the axial splined portion 142 may include 18 straight
splined teeth, although other numbers of teeth may be used
depending on the application. The helical splined portion 146
engages with the helical bore 124 of the outer eccentric 120 to
transfer the linear motion of the key shaft 140 into rotational
motion of both the key shaft 140 and inner eccentric 130. The
helical splined portion 146 and the helical bore 124 may include
helical splines with a spline angle of approximately 60 degrees to
slightly less than 90 degrees from the drum axis 19, although any
spline angle that permits the linear motion of the key shaft 140 to
be transferred to rotational motion of the key shaft 140 may also
be used.
[0026] The linear actuator 150 has an axially extending rod 152
that engages the key shaft 140. The linear actuator 150 has an
extension stroke where the rod 152 extends out from the linear
actuator 150, and a retraction stroke where rod 152 retracts into
the linear actuator 150. As the rod 152 extends along the drum axis
19, it pushes the key shaft 140 along the drum axis 19. This linear
motion is then converted into rotational motion of the key shaft
140 and inner eccentric 130 with the helical spline interface
between the helical bore 124 and the helical splined portion 146.
The linear actuator 150 may be a hydraulic or electric actuator and
may be mounted to the machine 10 through a mounting plate (not
shown) that is secured to the main frame 18 via rubber mounts (not
shown). Alternately, the linear actuator 150 may be mounted to the
main frame 18 through some other way known in the art, such as by
mounting the linear actuator 150 to one of the offset gearboxes 46
through a flange 154. The linear actuator 150 may be driven by one
of the power sources 22, 24, or by another power source (not
shown). The rod 152 may engage the key shaft 140 through an adapter
180. The adapter 180 may be mounted to the key shaft 140 through a
bearing 174 and may also include a physical stop such as a set
screw or key (not shown) for the outer race of the bearing 174
and/or the rod 152. The physical stop serves to prevent the rod 152
from rotating at the same rate as the key shaft 140, which in turn
rotates at the same rate as the vibratory motor 110. The seals of
the linear actuator 150 may not be able to handle the high rate of
speeds of the vibratory motor 110, which may exceed 3800
revolutions per minute. The linear actuator 150 also includes a
position sensor 156, which senses the linear extension of the rod
152 along the drum axis 19.
[0027] FIG. 3 shows the vibratory mechanism 100 with the outer
eccentric 120 and inner eccentric 130 in phase with each other
about the drum axis 19. When the outer and inner eccentrics 120,
130 are in phase and rotated by the vibratory motor 110, the drum
14 produces a maximum amplitude. FIG. 4 shows the vibratory
mechanism 100 with the outer eccentric 120 and the inner eccentric
130 180 degrees out of phase with each other about the drum axis
19. When the outer and inner eccentrics 120, 130 are 180 degrees
out of phase and rotated by the vibratory motor 110, the drum 14
produces a minimum amplitude.
[0028] When the outer and inner eccentrics 120, 130 are 180 degrees
out of phase, as seen in FIG. 4, a radial alignment hole 128 in the
lobe 126 of the outer eccentric 120 aligns with a similar radial
alignment hole 138 in the inner eccentric 130. Due to tolerance
stack-up in the manufacture of the vibratory mechanism 100, these
alignment holes 128, 138, in combination with a clamp-nut 160,
allow the vibratory mechanism 100 to be calibrated. When the outer
and inner eccentrics 120, 130 are out of phase with each other, a
rod (not shown) may be inserted into both radial alignment holes
128, 138. The clamp-nut 160 is then placed over the key shaft 140,
butted up against the helical side stub shaft 122, and locked onto
the key shaft 140. If the minimum extension position of rod 152 is
used to define the maximum amplitude (as seen in FIG. 3), the
clamp-nut 160 provides a physical stop for the extension of rod 152
for the minimum amplitude. Note that the alignment holes 128, 138
may alternately be positioned in the outer and inner eccentrics
120, 130 such that they align when they are in phase, at the
maximum amplitude. In such a case, the physical interference of
clamp-nut 160 against the helical side stub shaft 122 would
indicate the maximum amplitude, and a minimum extension of rod 152
would represent the minimum amplitude.
INDUSTRIAL APPLICABILITY
[0029] The disclosed vibratory mechanism and drum for a machine may
be used to provide a variably adjustable amplitude ranging from a
maximum to a minimum for any compactor machine. In one exemplary
embodiment, the vibratory mechanism is for a vibratory compactor,
such as a double split drum asphalt compactor.
[0030] In operation, as the machine 10 is driven over the
compactable material 12, the frequency and amplitude of the
vibratory system 90 may be manually controlled by an operator or
automatically controlled by an intelligent compaction system. The
frequency of impacts may be controlled by increasing or decreasing
the speed of the vibratory motor 110, with feedback from the speed
sensor 116. The amplitude of the impacts may be controlled by
brining the inner eccentric 130 in phase or out of phase with the
outer eccentric 120. Starting from a maximum amplitude position as
depicted in FIG. 3, the rod 152 of the linear actuator 150 may be
extended. As the rod 152 is extended, the key shaft 140, which is
rotatably secured to the inner eccentric 130, is pushed along the
drum axis 19 into the straight splines of bore 132 of the inner
eccentric 130. The helical spline interface between the helical
bore 124 and the helical splined portion 146 converts the linear
motion of the key shaft 140 and rod 152 into rotational movement of
the inner eccentric 130 with respect to the outer eccentric 120.
When the inner eccentric 130 and outer eccentric 120 are 180
degrees out of phase with each other, a position of minimum
amplitude has been reached, and the clamp-nut 160 provides a
physical stop for the further extension of rod 152. Similarly, the
amplitude of the vibratory system 90 may be decreased by retracting
the rod 152 into the linear actuator 150, moving from the position
of FIG. 4 to the position shown in FIG. 3. Intermediate amplitudes
less than the maximum or greater than the minimum may be obtained
by setting the phase angle of the inner eccentric 130 to the outer
eccentric 120 between 0 and 180 degrees. The position sensor 156
may be used to provide feedback to an operator via a display or to
the intelligent compaction system.
[0031] While the disclosure has been described with reference to
details of the illustrated embodiments, these details are not
intended to limit the scope of the disclosure as defined in the
appended claims. For example, the vibratory motor may be coupled to
the inner eccentric and the linear actuator may be coupled to the
outer eccentric. Other aspects, objects and advantages of this
disclosure can be obtained from a study of the drawings, the
disclosure, and the appended claims.
* * * * *