Abstract:
Disclosed is an excavating machine, representatively a tracked excavator, 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 limit positions. The bucket may be operated independently of the breaker for digging operations. Similarly, the breaker may be operated independently of the bucket for refusal material-breaking operations. The same excavating machine may now use the bucket and breaker in a rapid and continuous exchange to permit frequent removal of small quantities of broken refuse material with the bucket, exposing the bucket and breaker to fresh refuse material. The excavating machine disclosed incorporates an impact resistant deployment system with bifurcated and lubricated trunnion pivots and an in-line pivot restriction, or stop. The system provides a breaker assembly connection that permits quick installation and removal of the breaker, and significantly greater durability.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   This application is a continuation-in-part of U.S. application Ser. No. 10/871,898, filed Jun. 18, 2004 now U.S. Pat. No. 7,117,618, which is a continuation-in-part of U.S. application Ser. No. 10/150,057, filed May 17, 2002, now U.S. Pat. No. 6,751,896, which is a continuation-in-part of U.S. application Ser. No. 09/624,099, filed Jul. 24, 2000, now U.S. Pat. No. 6,430,849. This is also a continuation of U.S. application Ser. No. 11/362,670, filed Feb. 27, 2006. All applications from which priority is claimed are hereby incorporated by reference. 

   TECHNICAL FIELD OF THE INVENTION 
   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 
   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. 
   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. 
   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. 
   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. 
   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. 
   Another attempt to solve this problem is disclosed in U.S. Pat. No. 6,085,446 and U.S. Pat. No. 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. Pat. No. 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. 
   Another attempt to solve this problem is disclosed in U.S. Pat. No. 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. 
   Another attempt to solve this problem is disclosed in U.S. Pat. No. 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. 
   A more recent attempt to solve this problem is disclosed in U.S. Pat. No. 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 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. 
   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. Pat. No. 6,751,896. 
   SUMMARY OF THE INVENTION 
   The present invention is a marked improvement over the designs disclosed in U.S. Pat. No. 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. 
   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. 
   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, 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&#39;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. 
   A primary advantage of the present invention&#39;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. 
   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 pivotally 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. 
   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. 
   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. 
   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 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. 
   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. 
   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. 
   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. 
   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 
       FIG. 1  is a side view of an excavating machine. 
       FIG. 2  is an isometric view of a breaker assembly depicted in  FIG. 1 . 
       FIG. 3  is a side view of the breaker assembly and boom stick of  FIG. 2 . 
       FIG. 4  is an exploded view of the breaker assembly of  FIG. 1 . 
       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. 
       FIG. 6  is a top view of a bracket of the breaker assembly of  FIG. 1 . 
       FIG. 7  is a side view of the bracket of  FIG. 6 . 
       FIG. 8  is an isometric view of the bracket of  FIG. 6 . 
       FIG. 9  is an isometric view of a trunnion of the breaker assembly of  FIG. 2 . 
       FIG. 10  is a front view of the trunnion of the breaker assembly of  FIG. 2 . 
       FIG. 11  is a side cross-sectional view of the trunnion of the breaker assembly of  FIG. 2 . 
       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 
   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. 
     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 . 
   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. 
     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 . 
   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 . 
     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 . 
   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 ). 
   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. 
   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 . 
     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 . 
     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. 
   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 . 
   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. 
     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 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 . 
   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. 
   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 
   Experience in field operation of an excavating tool in accordance with the disclosure of U.S. Pat. No. 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 . 
   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. 
   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 , 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 . 
   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 . 
   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 . 
   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 . 
   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 . 
   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 . 
   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 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. 
   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. 
   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 . 
   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. 
   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 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 . 
   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 . 
   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 . 
     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 . 
   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 . 
   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 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. 
   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.