Note: Descriptions are shown in the official language in which they were submitted.
CA 02595387 2007-11-14
IlVIPACT RESISTANT BREAKER DEPLOYMENT SYSTEM
FOR AN EXCAVATING MACHINE
TECHNICAL FIELD OF THE INVENTION
[003] The present invention generally relates to a material handling apparatus
and, in
a preferred embodiment thereof, more particularly relates to an excavating
machine,
representatively a tracked excavator, having operatively attached to the stick
portion of its boom
a specially designed combination bucket and breaker structure which uniquely
permits the
excavator operator to selectively carry out either digging or refusal material
breaking tasks
without having to change out equipment on the stick.
BACKGROUND OF THE INVENTION
[004] Large scale earth excavation operations are typically performed using a
powered
excavating apparatus, such as a tracked excavator, having an articulated,
hydraulically pivotable
.
boom structure with an elongated, pivotal outer end portion commonly referred
to as a "stick"
Secured to the outer end of the stick is an excavating bucket which is
hydraulically pivotable
relative to the stick between "closed" and "open" positions. By pivotally
manipulating the stick,
with the bucket swung to a selected operating position, the excavator operator
uses the bucket
to forcibly dig into the ground, scoop up a quantity of dirt, and move the
scooped up dirt
quantity to another location, such as into the bed of an appropriately
positioned dump truck.
CA 02595387 2007-07-30
[005] A common occurrence during this conventional digging operation is that
the
bucket strikes refusal material (in excavation parlance, a material which
"refuses" to be dug
up) such as rock which simply cannot be broken and scooped up by the bucket.
When this
occurs it is typical practice to stop the digging operation, remove the bucket
from the stick,
and install a hydraulically operated "breaker" on the outer end of the stick
in place of the
removed bucket. The breaker has, on its outer end, an oscillating tool portion
which rapidly
hammers the refusal material in a manner breaking it up into portions which
can be
subsequently dug up. After the breaker has been utilized to break up the
refusal material,
the operator removes the breaker from the stick, replaces the breaker with the
previously
removed bucket, and resumes the digging operation with the bucket.
[006] While this procedure is easy to describe, it is a difficult, laborious
and time-
consuming task for the operator to actually carry out due to the great size
and weight of both
the bucket and breaker which must be attached to and then removed from the
stick, and the
necessity for the operator to climb into and out of the high cab area of the
excavator (often in
inclement weather) to effect each bucket and breaker change-out on the stick.
This
sequence of bucket/breaker/bucket change-out, of course, must be laboriously
repeated
each time a significant refusal area is encountered in the overall digging
process.
[007] A previously utilized alternative to this single excavator sequence is
to simply
provide two excavators for each digging project - one excavator having a
bucket attached to
its boom stick, and the second excavator having a breaker attached to its boom
stick. When
the bucket-equipped excavator encounters refusal material during the digging
process, it is
simply moved away from the digging site, and the operator climbs down from the
bucket-
equipped excavator, walks over to and climbs up into the breaker-equipped
excavator, drives
the breaker-equipped excavator to the digging site, and breaks up the
encountered refusal
material. Reversing the process, the operator then switches to the bucket-
equipped
excavator and resumes the digging process to scoop up the now broken-up
refusal material.
[008] While this digging/breaking technique is easier on the operator, it is
necessary
to dedicate two large and costly excavators to a given digging task, thereby
substantially
increasing the total cost of a given excavation task. A modification of this
technique is to use
two operators - one to operate the bucket-equipped excavator, and one to
operate the
breaker-equipped excavator. This, of course, undesirably increases both the
manpower and
equipment cost for a given excavation project.
2
CA 02595387 2007-07-30
[009] Another attempt to solve this problem is disclosed in U.S_ Patent
6,085,446
and U.S. Patent 4,100,688 for an excavating machine having a motorized milling
tool
attached to the back of the bucket. A primary disadvantage of these devices is
complexity,
cost, and reliability. Another disadvantage is the weight that must be
continuously carried by
the bucket. The additional weight substantially reduces the carrying capacity
and mobility of
the bucket. Another disadvantage to the device of U.S. Patent 6,085,446 is
that the back of
the bucket cannot be used to smooth or pad the soil, as is a well-known
practice in the
industry. Another disadvantage is that surface rock is not subject to an
overburden pressure,
so it generally fails faster under compression and impact forces than by the
shearing forces
of a scraping and gouging rotary drilling tool.
[010] Another attempt to solve this problem is disclosed in U.S. Patent
4,070,772 for
an excavating machine having a hydraulic breaker housed inside, or on top of,
the boom
stick. A primary disadvantage of this device is that it is extremely complex
and expensive.
Another disadvantage of this device is that it cannot be retrofit to existing
excavators.
Another disadvantage of this device is that the size of the breaker is
limited. Another
disadvantage of this device is that the bucket must be fully stowed to access
the breaker and
vice versa, making simultaneous operation impractical.
[011] Another attempt to solve this problem is disclosed in U.S. Patent
5,689,905 for
another excavating machine having a hydraulic breaker housed inside, or on top
of, the
boom stick. In this device, the chisel portion of the breaker is removed when
not in use. A
primary disadvantage of this device is that it fails to permit immediate,
unassisted switching
from breaker to bucket, and thus simultaneous operation is impossible. Another
disadvantage of this device is that it requires manual handling of the
extremely heavy chisel
tool each time the operator desires to convert to a breaker or bucket
operation. Another
disadvantage of this device is that it is extremely complex and expensive.
Another
disadvantage of this device is that it cannot be retrofit to existing
excavators.
[012] A more recent attempt to solve this problem is disclosed in U.S. Patent
6,751,896 for an excavating machine having a boom stick portion on which both
an
excavating bucket and a hydraulic breaker are mounted for hydraulically driven
pivotal
movement between first and second positions. A deployment system is disclosed
having a
bracket for closely aligned pivotal support of both the breaker and a single
hydraulic cylinder
on a single bracket. While this design is a marked improvement over the prior
art, its primary
3
CA 02595387 2007-07-30
disadvantage is that it lacks the desired level of durability at the first
pivot and extension
limiting (stop) mechanisms to tolerate the massive reciprocating loads of
operation over time.
Another disadvantage is that it is difficult to disassemble the first pivot to
replace tool
components. Another disadvantage is that the means for lubricating the bearing
surface of
the first pivot was ineffective and weakened the first pivot assembly. Another
disadvantage
is that it suffers durability loss from exposure of mechanical fasteners to
the excavated
material.
[013] As can be readily appreciated from the foregoing, a need exists for an
improved design for carrying out the requisite digging and refusal material-
breaking portions
of an overall excavation operation in a manner eliminating or at least
substantially eliminating
the above-mentioned problems, limitations and disadvantages commonly
associated with
conventional digging and breaking operations. It is to this need that the
present invention is
directed. In particular, there is a need for a new design with superior
durability to the designs
disclosed in U.S. Patent 6,751,896.
SUMMARY OF THE INVENTION
[014] The present invention is a marked improvement over the designs disclosed
in
U.S. Patent 6,751,896. In carrying out principles of the present invention, in
accordance with
a preferred embodiment thereof, an excavating machine, representatively a
tracked
excavator, is provided with a specially designed pivotable boom stick assembly
that includes
a boom stick having first and second excavating tools secured thereto for
movement relative
to the boom stick. Illustratively, the first excavating tool is an excavating
bucket secured to
the boom stick for pivotal movement relative thereto between a first position
and a second
position, and the second tool is a breaker secured to the boom stick for
pivotal movement
relative thereto between a stowed position and an operative position.
[015] A hydraulically operable drive apparatus is interconnected between the
boom
stick and the bucket and breaker and is usable to pivotally move the bucket
between its first
and second positions, and to pivotally move the breaker between its stowed and
operative
positions. Representatively, the drive apparatus includes a plurality of
hydraulic cylinder
assemblies operatively interconnected between the boom stick and the bucket
and breaker.
[016] The bucket, when the breaker is in its stowed position, is movable by
the drive
apparatus to the second bucket position and is usable in conjunction with the
boom stick,
4
CA 02595387 2007-07-30
and independently of the breaker, to perform a digging operation. The breaker,
when the
bucket is in its first position, is movable by the drive apparatus to the
breaker's operative
position and is usable in conjunction with the boom stick, and independently
of the bucket, to
perform a breaking operation. Accordingly, the excavating machine may be
advantageously
utilized to perform both digging and breaking operations without equipment
change-out on
the boom stick.
[017] A primary advantage of the present invention's various embodiments is
that it
provides an extremely durable trunnion assembly for pivotal connection of the
tool to the
bracket. Another advantage is that it provides a new and durable stop
mechanism,
configured to avoid distortion of the side plates. Another advantage is that
it is easy to
disassemble the trunnion assembly to replace or service tool components.
Another
advantage is that it provides a reliable and effective means for lubricating
the bearing surface
of the trunnion assembly to ensure reliable operation of the tool.
[018] In accordance with a preferred embodiment thereof, an excavating tool
system for use on an excavating machine is provided. A bracket is located on
the underside
of a boom stick. The bracket has a first pivot and a second pivot. The first
pivot is a
trunnion. An excavating tool is pivotally secured at one end to the trunnion.
The excavating
tool has a third pivot located thereon between its one end and its opposite
end. A hydraulic
cylinder is pivotafly secured at one end to the second pivot and pivotally
secured on its
opposite end to the third pivot. In the preferred embodiment, the pivotal
attachment of the
excavating tool to the bracket is bifurcated, thus comprising a pair of
coaxial trunnions.
[019] In the preferred embodiment, the centers of the trunnions are located
coaxially
on the bracket sides slightly further from base than the location of the
second pivot.
[020] In a preferred embodiment of the present invention, each trunnion
comprises
an outer plate and a cylindrical bearing extending from the outer plate. A
plurality of bolt
holes extends through the outer plate and the sleeve bearing. In a more
preferred
embodiment, a hub extends from the sleeve bearing. In the more preferred
embodiment, the
outer plate and hub are also cylindrical.
[021] The mounting bracket further comprises a base and a pair of parallel
bracket
sides extending upward from the base, each having a hub socket and a plurality
of threaded
CA 02595387 2007-07-30
holes arranged generally symmetrically around the hub sockets. The threaded
holes are
aligned with the bolt holes for receiving threaded fasteners (such as bolts)
for attaching the
trunnions to the mounting bracket sides.
[022] In a more preferred embodiment, the trunnion further comprises a
lubrication
system. In the preferred embodiment, the lubrication system comprises a bore
in the outer
plate. A fluid channel extends from the bore to the outer surface of the
bearing. A lubrication
connection, such as a grease cert, is attached to the fluid channel inside the
bore.
[023] In another preferred embodiment of the present invention, a stop is
formed on
each bracket side. A stop bar is located on one end of the excavating tool
such that the stop
bar engages the stop members to limit the pivotal rotation of the excavating
tool.
[024] These embodiments have the advantage of being easily retrofit onto
excavating machines without modification of the hydraulic system. An
additional advantage
is the lower cost of materials and installation. Optionally, an uncontrolled
hydraulic or
pneumatic cylinder may be used to prevent free fall of the breaker upon
release of the latch-
lock. An advantage of this embodiment is increased safety.
[025] The foregoing has outlined rather broadly the features and technical
advantages of the present invention in order that the detailed description of
the invention that
follows may be better understood. Additional features and advantages of the
invention will
be described hereinafter which form the subject of the claims of the
invention. It should be
appreciated by those skilled in the art that the conception and the specific
embodiment
disclosed may be readily utilized as a basis for modifying or designing other
structures for
carrying out the same purposes of the present invention. It should also be
realized by those
skilled in the art that such equivalent constructions do not depart from the
spirit and scope of
the invention as set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[026] FIG. 1 is a side view of an excavating machine.
[027] FIG. 2 is an isometric view of a breaker assembly depicted in FIG. 1.
[028] FIG. 3 is a side view of the breaker assembly and boom stick of FIG. 2.
6
CA 02595387 2007-07-30
[029] FIG. 4 is an exploded view of the breaker assembly of FIG. 1.
[030] FIG. 5 is an isometric view of the breaker assembly and boom stick of
FIGS. 2
and 3, shown with a side plate removed for visibility.
[031] FIG. 6 is a top view of a bracket of the breaker assembly of FIG. 1.
[032] FIG. 7 is a side view of the bracket of FIG. 6.
[033] FIG. 8 is an isometric view of the bracket of FIG. 6.
[034] FIG. 9 is an isometric view of a trunnion of the breaker assembly of
FIG. 2.
[035] FIG. 10 is a front view of the trunnion of the breaker assembly of FIG.
2.
[036] FIGS. 11 is a side cross-sectional view of the trunnion of the breaker
assembly of FIG. 2.
[037] FIG. 12 is an exploded view of the trunnion and bracket of the breaker
assembly of FIGS. 2 and 3.
DETAILED DESCRIPTION OF THE INVENTION
[038] Refer now to the drawings wherein depicted elements are, for the sake of
clarity, not necessarily shown to scale and wherein like or similar elements
are designated by
the same reference numeral through the several views.
[039] FIG. 1 discloses earth-excavating machine 10 in accordance with a
preferred
embodiment of the present invention. A breaker assembly 100 is mounted on boom
stick
200 in addition to excavating bucket 300. Breaker assembly 100 is an
excavating tool
pivotally attached to excavating machine 10 at a first pivot 102, a second
pivot 104, and a
third pivot 106. A bracket 140 is rigidly attached to boom stick 200 by
welding or other
means of secure attachment. In the preferred embodiment, breaker assembly 100
is
pivotally attached to a bifurcated first pivot 102 on bracket 140.
7
CA 02595387 2007-07-30
[040] A single hydraulic cylinder assembly 110 is pivotally attached at one
end to
second pivot 104 on bracket 140. Hydraulic cylinder assembly 110 is pivotally
attached at its
other end to third pivot 106 on breaker assembly 100. In the most preferred
embodiment,
the distance between first pivot 102 and second pivot 104 is less than the
distance between
first pivot 102 and the third pivot 106. A latch 190 is located on boom stick
200. When
breaker assembly 100 is in the retracted position, latch 190 engages strike
132 (best seen in
FIG. 4) so that breaker assembly 100 remains in the locked or stowed position.
[041] FIGS. 2 and 3 are isometric and side views, respectively, of an
alternative
mounting system. FIG. 2 illustrates bracket 140 and latch 190 of FIG.1
attached to a plate
202 by welding or other similarly secure means. In this embodiment, latch 190
can be
located in proper alignment with bracket 140 and breaker assembly 100 on plate
202 prior to
installation on excavating machine 10. Plate 202 can then be attached to boom
stick 200.
The other embodiment options disclosed herein are independent of whether plate
202 is
used or not, and the various embodiments of the invention are not dependent
upon the
attachment option illustrated in FIGS. 2 and 3.
[042] As shown in FIG 1, bracket 140 is attached to boom stick 200. Referring
to
FIG. 2, one end of hydraulic cylinder 110 is pivotally coupled to bracket 140.
The opposite
end of hydraulic cylinder 110 is pivotally coupled to third pivot 106 between
a first body
section 112 and a second body section 114. Body sections 112 and 114 are
pivotally
coupled to bifurcated first pivot 102. First pivot is comprised of a pair of
coaxial trunnions
160 located on bracket 140.
[043] FIG. 4 is an exploded view of breaker assembly 100 of FIG. 1. The
principal
component of breaker assembly 100 is reciprocating breaker 180, also known as
a hammer.
Breaker 180 has a replaceable cutting tool 182 extending from one end. A
breaker end 184
is located on the end of breaker 180 opposite tool 182.
[044] In FIG. 4, body sections 112 and 114 are illustrated uncoupled. A hollow
bushing 116 is provided on each of body section 112 and 114 for receiving
trunnion 160 for
attachment to bracket 140. A series of aligned holes 118 are provided on body
sections 112
and 114 for assembly of breaker assembly 100. In the preferred embodiment,
bolt protectors
120 are provided on the exterior of one of body section 112 or 114 (shown on
body section
112).
8
CA 02595387 2007-07-30
[045] A pair of opposing lower lock plates 122 and a pair of upper lock plates
124
are provided for securing breaker 180 between body sections 112 and 114.
Aligned holes
118 are also located on lower lock plates 122 and upper lock plates 124. Lock
plates 122
and 124 are secured between breaker 180 and body sections 112 and 114 by nut
and bolt
assemblies 126 passing through aligned holes 118. In the preferred embodiment,
the nuts of
nut and bolt assemblies 126 are of the acorn type.
[046] A stop bar 128 is provided for bolted attachment between body sections
112
and 114 at aligned holes 118. A pivot bar 130 is provided for bolted
attachment between
body sections 112 and 114 at aligned holes 118. Third pivot 106 is comprised
of pivot bar
130. A strike 132 is provided for bolted attachment between body sections 112
and 114 at
aligned holes 118.
[047] FIG. 5 is an isometric view of breaker assembly 100 and boom stick 200
(or
plate 202) of FIGS. 2 and 3, shown with body section 112 of breaker assembly
100 removed
for visibility. In this view, breaker assembly 100 is shown in the fully
extended position. As
seen in this view, stop member 152 is secured between body sections 112 and
114, and is
located in adjacent contact with breaker end 184 of breaker 180.
[048] FIGS. 6-8 are top, side, and isometric views, respectively, of bracket
140, in
which bracket 140 is illustrated in detail. Bracket 140 comprises a base 142
and a pair of
bracket sides 144 extending upwards from base 142 in substantially parallel
relationship.
[049] Second pivot 104 comprises a pivot bar 146 located between bracket sides
144. In the preferred embodiment, a pair of hub sockets 148 is coaxially
located in bracket
sides 144. A series of bolt holes 150 are located generally symmetrically in
each of bracket
sides 144. In a more preferred embodiment including hub sockets 148, bolt
holes 150 are
located generally symmetrically around hub sockets 148 in bracket sides 144.
[050] In a preferred embodiment best seen in FIGS. 7 and 8, a stopping member
152 is formed on one end of each of bracket sides 144. Stop members 152 of
bracket sides
144 are in substantial alignment with one another.
[051] FIGS. 9-11 are isometric, front, and side cross-sectional views of
trunnion
160, in which trunnion 160 is illustrated in detail. Trunnion 160 has an outer
plate 162. A
9
CA 02595387 2007-07-30
cylindrical bearing 164 extends coaxially inwards from outer plate 162.
Bearing 164 contacts
bushing 116 in a bearing relationship when breaker assembly 100 is fully
assembled. In a
more preferred embodiment, a hub 166 extends coaxially inwards from bearing
164.
[052] In the preferred embodiment, a plurality of bolt holes 168 extend
through outer
plate 162 and cylindrical bearing 164 in generally symmetric relationship. In
a more
preferred embodiment including hub 166, bolt holes 168 are located in a ring
around hub
166. In a more preferred embodiment, bolt holes 168 include countersunk
portions 170 for
receiving the heads of bolts.
[053] In a more preferred embodiment, trunnion 160 further comprises a
lubrication
system 172. A lubrication connection 174, such as a grease nipple, is attached
to trunnion
160, preferably within a bore 176. A fluid channel 178 connects lubrication
connection 174 to
the surface of cylindrical bearing 164. Optionally, fluid channel 178 may
intersect the surface
of bearing 164 in more than one location.
OPERATION OF THE PREFERRED EMBODIMENTS
[054] Experience in field operation of an excavating tool in accordance with
the
disclosure of U.S. Patent 6,751,896 has disclosed the opportunity for
improvements in the
invention of that patent, which are particular to an excavating machine having
a deployable
hammer pivotally attached to a boom stick. Specifically, the deployment system
may suffer
premature destruction of breaker assembly 100.
[055] Referring to FIGS. 1 through 5 of the drawings, the reference numeral
100
generally designates a breaker assembly. Breaker assembly 100 is specifically
designed to
couple to either a new or existing boom arm, such as boom stick 200, allowing
easy retrofit
onto excavating machines without modification of the hydraulic system. In an
alternative
mounting arrangement, bracket 140 and latch 190 can be welded to a flat plate
202. By this
method, breaker assembly 100 and latch 190 can be pre-aligned, simplifying and
accelerating the installation of the device.
[056] The disclosed configuration allows an excavating machine 10 to have
multiple
uses, and therefore reduce the cost of operation. The deployment and
retraction of breaker
assembly 100 is accomplished by the relationships between breaker assembly
100, boom
stick 200, and hydraulic cylinder 110, as associated with the configuration
first pivot 102,
CA 02595387 2007-07-30
second pivot 104, and third pivot 106. In the most preferred embodiment, the
distance
between first pivot 102 and the second pivot 104 is less than the distance
between first pivot
102 and third pivot 106.
[057] As illustrated in FIG. 1, first pivot 102 and second pivot 104 are
located on
bracket 140. In the preferred embodiment, first pivot 102 is bifurcated. This
configuration
allows for the most complete retraction of breaker assembly 100 without
physically interfering
with first pivot 102. Hydraulic cylinder assembly 110 is pivotally attached at
one end to
second pivot 104 on bracket 140. Hydraulic cylinder assembly 110 is pivotally
attached at its
other end to third pivot 106 on breaker assembly 100. A latch 190 secures
breaker assembly
100 in a retracted position. Release of latch 190 and expansion of hydraulic
cylinder 110
results in quick rotation and deployment of breaker assembly 100.
[058] In the preferred embodiment, first pivot 102 is comprised of a pair of
coaxial
trunnions 160 located on bracket 140. Trunnions 160 are fully illustrated in
FIGS. 9, 10 and
11. Trunnions 160 provide pivotal coupling between breaker assembly 100 and
bracket 140.
[059] Second pivot 104 comprises pivot bar 146, which extends between sides
144.
Pivot bar 146 provides pivotal coupling between hydraulic cylinder 110 and
bracket 140.
[060] Third pivot 106 comprises a pivot bar 130 coupled between body sections
112
and 114. Pivot bar 130 provides pivotal coupling between hydraulic cylinder
110 and breaker
assembly 100.
[061] As seen in FIGS. 6 through 8, bracket 140 is comprised of three main
pieces:
a base 142 and a pair of substantially parallel sides 144 extending
orthogonally upwards
from base 142. Coaxial hub sockets 148 are located on sides 144. Bolt holes
150 are
located symmetrically around hub sockets 148. Stop members 152 are located on
one end
of sides 144.
[062] As seen in FIGS. 9-11, each trunnion 160 is comprised of outer plate
162,
cylindrical bearing 164, and hub 166. Bolt holes 168 are located symmetrically
through outer
plate 162 and cylindrical bearing 164. When trunnions 160 are inserted into
bushings 116 of
body sections 112 and 114, bolt holes 168 align with bolt holes 150 on bracket
sides 144.
This permits threaded fasteners to secure trunnions 160 to bracket 140.
Countersunk
11
CA 02595387 2007-07-30
portions 170 provide protection for the fasteners during excavating
activities, thus adding
durability to the system. Bushings 116 of body sections 112 and 114 are
located on bearings
164 in a bearing relationship when breaker assembly 100 is fully assembled.
[063] In a more preferred embodiment, trunnion 160 further comprises
lubrication
system 172. Lubrication system 172 comprises lubrication connection 174 at,
such as a
grease cert for adding grease, attached to fluid channel 178 within trunnion
160. Preferably,
lubrication connection 174 is located within bore 176 to provide protection
during excavating
activities, thus adding durability to the tool system. Fluid channel 178
connects lubrication
connection 174 to the surface of cylindrical bearing 164. Optionally, fluid
channel 178 may
intersect the surface of bearing 164 in more than one location.
[064] Lubrication system 172 thus provides the advantage of a protected and
accessible means of maintaining lubrication at first pivot 102, which receives
the heaviest
load and impacts of the system. The large bearing area provided by cylindrical
bearing 164,
when lubricated, has the advantage of distributing the significant impact
forces of operation
over a larger area. Similarly, the use of hubs 166 and multiple threaded
fasteners (not
illustrated) through bolt holes 150 to secure trunnions 160 to bracket 140
distributes the
impact forces of operation over the collectively larger cross-sectional area
of the multiple
fasteners and hubs 166.
[065] As best seen in FIG. 12, an advantage of a preferred embodiment of the
present invention is that use of trunnions 160 facilitates rapid installation
and removal of
breaker assembly 100 from excavation machine 10. This is necessary when
reciprocating
breaker 180 requires maintenance or replacement, as often occurs with high-
energy tools
operating in harsh environments.
[066] As illustrated in FIG. 4, aligned holes 118 are provided on body
sections 112
and 114 for assembly of breaker assembly 100. In the preferred embodiment,
bolt protectors
120 are provided on the exterior of one of body section 112 or 114 (shown on
body section
112) for receiving the bolt portions of nut and bolt assemblies 126.
Additionally, in the
preferred embodiment, the nut portions of nut and bolt assemblies 126 are of
the acorn type.
It has been found that fastener heads such as bolt heads and nuts can be
quickly destroyed
during excavating procedures making breaker assembly 100 difficult to remove
and service.
Thus, the configured fasteners 126 and protectors 120 provide the advantage of
increased
12
CA 02595387 2007-07-30
durability. Additionally, bolt protectors secure bolt portions of nut and bolt
assemblies 126
from rotation, therefore having the advantage of simplifying service by only
needing to apply
torque tooling, such as a wrench, to the nuts portions of nut and bolt
assemblies 126 located
on one of body sections 112 or 114.
[067] Nut and bolt assemblies 126 connect through aligned holes 118 to secure
lower lock plates 122 and upper lock plates 124 around breaker 180 and between
body
sections 112 and 114. Additionally, nut and bolt assemblies 126 connect
through aligned
holes 118 to secure pivot bar 130, stop bar 152, and strike 132 between body
sections 112
and 114 at aligned holes 118. Stop bar 152 is located immediately adjacent to
breaker end
184 of breaker 180.
[068] Strike 132 provides a means of engagement with latch 190 when it is
desired
to retain breaker assembly 100 in the retracted, or stowed, position. The
retracted, or
stowed, position is illustrated in FIG. 1.
[069] FIG. 5 is an isometric view of breaker assembly 100 and boom stick 200
(or
plate 202) with side 112 of breaker assembly 100 removed for visibility. In
this view, breaker
assembly 100 is shown in the fully extended position. It is necessary to limit
the maximum
extension of breaker assembly 100 to prevent damage to hydraulic cylinder 110.
It is in the
fully extended position that reciprocal breaker 180 is operating and engaging
formation or
matter for destruction and, thus, the position in which highest impact forces
are being
imparted to excavating machine 10 and breaker assembly 100.
[070] In a preferred embodiment of the present invention illustrated in FIG.
5, stop
members 152 on bracket 140 engage stop bar 128, which is abutted to breaker
end 184 of
breaker 180. Instead of transferring the impact forces of operation to body
sections 112 and
114, the forces are transferred directly to boom stick 200 through breaker
180, stop bar 128
and bracket 140. This configuration has the advantage of preventing separation
of body
sections 112 and 114 and premature failure of breaker assembly 100 during
operation.
Besides a substantial increase in durability, this configuration simplifies
construction of
breaker assembly 100 and bracket 140.
[071] Another advantage of the present invention is that the bucket can be
operated
without fully stowing the breaker. Likewise, the breaker may be operated
without the
13
CA 02595387 2007-07-30
necessity to fully extend the bucket. This increases the efficiency of the
excavation process
by providing immediate access to each of the tools, without delay. Another
advantage of this
capability is that it further increases the efficiency of the excavation
process by rendering the
bucket available to frequently scrape away the freshly generated cuttings so
the breaker tool
is always exposed to fresh refusal material, avoiding operation against
previously generated
cuttings. Another advantage of this capability is that by avoiding operation
against previously
generated cuttings, the breaker tool will last longer.
[072] Having thus described the present invention by reference to certain of
its
preferred embodiments, it is noted that the embodiments disclosed are
illustrative rather than
limiting in nature and that a wide range of variations, modifications,
changes, and
substitutions are contemplated in the foregoing disclosure and, in some
instances, some
features of the present invention may be employed without a corresponding use
of the other
features. Many such variations and modifications may be considered obvious and
desirable
by those skilled in the art based upon a review of the foregoing description
of preferred
embodiments. Accordingly, it is appropriate that the appended claims be
construed broadly
and in a manner consistent with the scope of the invention.
14
