Excavating bucket with replaceable wedge-locked teeth

Information

  • Patent Grant
  • 6675509
  • Patent Number
    6,675,509
  • Date Filed
    Thursday, May 23, 2002
    23 years ago
  • Date Issued
    Tuesday, January 13, 2004
    22 years ago
  • Inventors
  • Examiners
    • Pezzuto; Robert E.
    Agents
    • Townsend and Townsend and Crew LLP
Abstract
An excavating bucket assembly for excavation apparatus that does not use pins to connect teeth to adaptors on the excavation bucket. Each adaptor includes a receiving portion defined therein that is at least partially defined by an abutment wall. Each tooth includes an interference portion. The connection system includes a biasing portion adjacent the abutment wall and a locking portion adjacent the biasing portion. The locking portion includes a locking section and an interference section that engages the interference portion of its respective tooth. The locking section and the interference section are capable of movement relative to one another to thereby couple the tooth to the adaptor. The locking section included at least one biasing plunger that engaged a corresponding biasing pin within the biasing portion when the connection system is in use.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to digging buckets for excavation vehicles and equipment such as front-end loaders and, more particularly, to a connection system for connecting replaceable teeth to such digging buckets.




2. Description of the Prior Art




Excavating buckets are used extensively in the construction and mining industries. The buckets are used with a variety of different excavating apparatus, such as backhoes, power shovels, front-end loaders, dragline equipment, etc., for digging, loading, etc. Although these buckets have many differences, they are generally formed with a rear wall, side walls, and a bottom wall. The walls cooperatively define an open front and a cavity for gathering earthen material and moving it to a dump site. The bottom edge of the open front is defined by a forward lip of the bottom wall. The lip is intended to engage the ground for collection of the earthen material into the bucket cavity. The lip may be formed to have a linear or arcuate-shaped edge or formed to have a particular configuration (such as V-shaped) to suit the desired operation. Similarly, the front edges of the side walls are also adapted to engage the ground.




Attachments are commonly mounted on the lip and front edges of the side walls to increase the effectiveness and durability of the buckets. These attachments typically include teeth, shrouds and wings. The teeth project forwardly of the lip to disrupt the material for enhanced collection of the material into the cavity. The shrouds are positioned in-between the teeth and are generally provided with an inclined surface to improve the collection of the material into the bucket. The wings are attached to the front edges of the side walls in general proximity with the lips. In any event, the attachments protect the bucket against undue wear. As a result, only the attachments normally need replacement when the front of the bucket becomes worn, thus prolonging the usable life of the larger and more expensive lip and side walls.




Generally, a tooth is attached to the lip with an adaptor. The tooth in turn is attached to the adaptor with a pin. In order to replace the tooth, the pin is knocked out with a large hammer. During this process, the pin is destroyed, which means that a new pin is needed to attach the new tooth to the adaptor. This is a non-desirable cost since pins typically cost in the range of $25.00-$50.00 each.




Furthermore, use of the large hammer to knock the pin out of the tooth-adaptor connection may be dangerous. There is a danger of injury to bodily parts, especially fingers, and also a danger from flying pieces or chips from the pin or other parts, or from dirt, debris, sand, dust, etc. in the connection area.




Another problem with current connection techniques lies in the fact that the interface between the tooth and its associated adaptor is not adequately sealed. Thus, dirt, sand, grit, and abrasives enter the interface between the tooth and adaptor and slowly grinds or wears the two parts. This wear loosens the tightness of the fit, and thus, new teeth may “wiggle” and may be quickly damaged or broken. Due to this wear, it is necessary to relatively frequently replace the adaptor. Currently, a new adaptor is required for every 10-20 teeth that are installed on the associated adaptor. The frequency of the replacement of the adaptor depends on the amount of use, the type of soil, etc.




SUMMARY OF THE INVENTION




In its broadest sense, the present invention provides a connection system for connecting a first item and a second item, the first item including a receiving portion defined at least partially by an abutment wall and the second item including an interference portion, wherein the connection system comprises a biasing portion and a locking portion adjacent the biasing portion. The biasing portion is adjacent the abutment wall when the connection system is in use and includes at least one biasing pin protruding from a rear wall. The locking portion includes a locking section and an interference section that engages the interference portion when the connection system is in use. The locking section and the interference section are capable of movement relative to one another. The locking section includes at least one biasing plunger that engages a corresponding one of the at least one biasing pin when the connection system is in use.




In a preferred embodiment, a digging bucket assembly for an excavation apparatus that includes a bucket body having a lip running longitudinally along the bottom front portion of the bucket body has a plurality of adaptors connected thereto. Each adaptor includes a receiving portion defined therein that is at least partially defined by an abutment wall. The digging bucket further includes a corresponding plurality of teeth each connected to a respective adaptor with a connection system. Each tooth includes an interference portion. The connection system includes a biasing portion adjacent the abutment wall when the connection system is in use with the biasing portion including at least one biasing pin protruding from a rear wall. The connection system further includes a locking portion adjacent the biasing portion wherein the locking portion includes a locking section and an interference section that engages the interference portion when the connection system is in use. The locking section and interference section are capable of movement relative to one another. A locking section further includes at least one biasing plunger that engages a corresponding one of the at least one biasing pins when the connection system is in use.




In accordance with one aspect of the present invention, the locking section and the interference section are separate pieces that are adjacent one another.




In accordance with another aspect of the present invention, the locking section is connected to the biasing portion via a hinge.




In accordance with a further aspect of the present invention, the interference section and the locking section each include an angled surface that are adjacent one another.




In accordance with yet another aspect of the present invention, the biasing portion includes at least three biasing pins and the locking section includes at least three biasing plungers.




In accordance with a further aspect of the present invention, the interference portion comprises a notched find within the tooth and the interference section comprises a projection.




In accordance with yet another aspect of the present invention, the locking section includes an indentation defined within a top surface that engages an edge of the tooth.




Accordingly, the present invention provides a connection system that is ideally suited for connecting teeth of a digging bucket to adaptors located along a front lip of the digging bucket without the need for pins. The connection system is easy to fabricate and, since it preferably extends within the width of the receiving portion of the adaptor, no dirt can enter between the tooth and the portion of the adaptor over which it extends. The locking portion of the connection system fully engages the tooth and the adaptor with the interference section fully engaging the interference portion of the tooth, thus providing a tight fit and helping prevent relative motion between the tooth and its associated adaptor.




A connection system in accordance with the present invention is reusable and thus, pin replacement is eliminated, thereby saving money for each tooth replacement. Furthermore, a connection system in accordance with the present invention may be easily removed to replace its associated tooth and thus, there is no need for a hammer, thereby reducing the possibility of injuries when replacing teeth.




Other features and advantages of the present invention will be understood upon reading and understanding the detailed description of the preferred exemplary embodiments found herein below, in conjunction with reference to the drawings, in which like numerals represent like elements.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a connection system in accordance with the present invention;





FIG. 2

is a perspective view of an alternative embodiment of a connection system in accordance with the present invention;





FIG. 3

is a perspective view of a tooth and its interior for use with digging buckets;





FIG. 4

is a side elevation view of the embodiment of the connection system illustrated in

FIG. 1

;





FIG. 5A

is a sectional view of the connection system illustrated in

FIG. 2

coupling a tooth to an adaptor;





FIG. 5B

is an enlarged sectional view of the connection system illustrated in

FIG. 2

coupling a tooth to a connector;





FIG. 6

is a perspective view of a dragline tooth and its interior;





FIG. 7

is a sectional view of a dragline tooth coupled to an adaptor with a connection system in accordance with the present invention;





FIG. 8

is a perspective view of an excavating apparatus;





FIG. 9

is a sectional view of an alternative embodiment of a tooth coupled to a adaptor; and





FIG. 10

is a sectional view of another alternative embodiment of a connection system in accordance with the present invention coupling a tooth to an adaptor.











DETAILED DESCRIPTION OF THE PREFERRED EXEMPLARY EMBODIMENTS




With reference to

FIG. 4

, a connection system


10


includes a biasing portion


11


and a locking portion


12


. Preferably, the biasing portion includes a biasing section


13


and an abutment section


14


. The locking portion preferably includes a locking section


15


and an interference section


16


. In a first preferred embodiment, both the biasing section and abutment section consist of an elastomeric material such as rubber, plastic, etc., while the locking section and interference section both preferably consist of a non-elastomeric material, most preferably, metal. In a preferred embodiment, interference section includes a projection


17


defined on an upper surface


18


.




In a preferred embodiment, biasing section


13


and abutment section


14


are coupled together via structure to inhibit their moving upward or “opening-up.” Preferably, this is accomplished with an over-center hinge


20


. Locking section


15


is preferably coupled to biasing portion


11


with a hinge


21


. Preferably, the hinge couples locking section


15


to biasing section


13


. The hinge is vulcanized to the rubber in a preferred embodiment and is connected to the metal locking section with a suitable connection such as a bolt, a weld, etc.




As will become apparent herein, interference section


16


and locking section


15


are capable of movement relative to one another. This may be accomplished by suitable connection means such as an elastomeric material, rollers, etc. In the preferred embodiment, locking section


15


and interference section


16


are two separate pieces. Preferably both locking section


15


and interference section


16


have angled surfaces


22


,


23


, respectively. When connection system


10


is used, angled surface


22


and angled surface


23


engage one another as can be seen in FIG.


4


. Hence, locking section


15


and interference section


16


preferably have substantially wedge shapes.




Connection system


10


also includes an assembly/disassembly portion


24


. Assembly/disassembly portion


24


includes a body


25


that engages over-center hinge


20


and a head


26


. Additionally, a slot


27


is defined within a top portion of body


25


.




Connection system


10


can be used for connecting two items that are appropriately configured for receiving the connection system. Connection system


10


is ideally suited for connecting a tooth


30


to an adaptor


31


. Adaptor


31


is connected to a front lip


32


of an excavation bucket


33


that is used with excavation equipment. Adaptor


31


and tooth


30


may be attached to any part of an excavation-type piece of machinery that uses such teeth.





FIG. 3

illustrates connection system


10


mounted within a receiving portion


34


defined within adaptor


31


. Receiving portion


34


includes an abutment wall


35


. To install the connection system, and thereby connect a tooth to an adaptor, the connection system is placed in the receiving portion in a “open” position, i.e., biasing section and abutment section have space between them. Interference section


16


is placed on locking section


15


such that their angled surfaces


22


,


23


are engaged. Tooth


30


is placed over interference section


16


such that projection


17


engages interference portion


36


defined within tooth


30


. Interference portion


36


, as can be seen in the drawings, is preferably a notch that cooperates with projection


17


to form an interference fit.




Once tooth


30


is in place such that projection


17


and interference portion


36


are cooperating, assembly/disassembly portion


24


is pushed at head


26


to force biasing section


13


and abutment section


14


together i.e., to substantially flatten connection system


10


. Back wall


40


of abutment section


14


engages abutment wall


35


. Preferably metal slide bars


41


are provided under biasing section


13


and abutment section


14


to allow these sections to slide along the metal surface of receiving portion


34


defined within adaptor


31


.




Locking section


15


is capable of sliding under interference section


16


as connection system


10


is flattened out. This helps pull tooth


30


tightly onto adaptor


31


. This self tightening feature of connection system


10


pulls a bottom portion


34


of tooth


30


tightly against a bottom portion


43


of nose


44


of adaptor


31


. A top portion


45


of tooth


30


has a slight clearance between a top portion


46


of adaptor


31


. In a current prototype embodiment of a tooth connected with connection system


10


to an adaptor, the clearance between top


45


and top


46


is approximately {fraction (1/32)} inches. Thus, a lower tolerance is required when manufacturing teeth


30


since connection system


10


has such a self-tightening feature.




Receiving portion


34


and connection system


10


have substantially the same width and preferably extend substantially along the width of the interior of teeth


30


. Additionally, the interior of teeth


30


and corresponding surfaces of the adaptors are form-fitted (except for the previously mentioned clearance area between the tops


45


,


46


). Thus, when connection system


10


is assembled and connecting a tooth to an adaptor, a seal is provided between the adaptor and the interior of the tooth. Accordingly, connection system


10


helps prevent sand, dirt, dust, abrasives, etc. and other debris from entering tooth


30


and “grinding” away at nose


44


of the adaptor, thereby prolonging the life of adaptor


31


.




To remove connection system


10


and replace tooth


30


, a prybar (not shown) or other suitable tool is used to pull assembly/disassembly portion


24


by engaging slot


27


, thereby “opening-up” biasing portion


11


. Connection system


10


may then be removed by pulling out biasing portion


11


thereby pulling out locking section


15


and disengaging interference section


16


from interference portion


36


. A new tooth is then placed onto the adaptor as previously described.




As stated previously, biasing portion


11


is preferably made of an elastomeric material, most preferably rubber. This allows connection system


10


to tightly and snugly fit within receiving portion


34


. When the bucket that includes the teeth/adaptor/connection system as described is used, lateral forces are transferred between the teeth and the adaptors due to their tight fit.




With reference to

FIGS. 2

,


5


A and


5


B, an alternative embodiment of connection system


10


′ includes a biasing portion


11


′ and a locking portion


12


′. The biasing portion includes a biasing portion


13


′ and an abutment section


14


′. Finally, connection system


10


′ includes interference section


16


′ that includes projection


17


′ on an upper surface


18


′.




Preferably, abutment section


14


′ consists of a non-elastomeric material, most preferably metal, and a biasing section


13


′ preferably consists of an elastomeric material such as rubber, plastic, etc. Preferably biasing section


13


′ consists of rubber. Preferably locking portion


12


′ consists of a non-elastomeric material, most preferably metal, and interference section


16


′ preferably consists of a non-elastomeric material, most preferably metal. Abutment section


14


′ is preferably connected to biasing section


13


′ with a hinge


21


′. A portion of the hinge is vulcanized into rubber biasing section


13


′ while another portion of hinge


21


′ is connected to locking portion


12


′ with bolts, weldings, etc.




Both locking portion


12


′ and interference section


16


′ preferably include angled surfaces


22


′,


23


′, respectively. When connection section


10


′ is used, interference section


16


′ engages locking portion


12


′ such that angled surface


23


′ engages angled surface


22


′.




Connection system


10


′ can assume a substantially wedge shape when it is not being used by folding locking portion


12


′ over biasing portion


11


′. Notch


50


defined within locking portion


12


′ is placed over hinge


21


.




To couple a tooth


30


with an adaptor


31


using connection system


10


′, interference section


16


′ is placed within receiving portion


34


. Tooth


30


is placed over interference section


16


′ such that interference portion


36


engages interference section


16


′. The front edge


51


of interference section


16


′ is lifted and locking portion


12


′ is placed under interference section


16


′. Connection system


10


′ is pushed snugly into receiving portion


34


such that abutment section


14


′ engages abutment wall


35


. Because of the angled surfaces


22


′,


23


′, locking portion


12


′ slides underneath interference section


16


′ and snugly pulls tooth


30


onto adaptor


31


as previously described. Once again because the tooth is form-fitted with the adaptor along the sides and bottom, but not the top, the tooth tightly and snugly is coupled to the nose of the adaptor. A clearance is once again provided along the top of the nose of the adaptor, which is sealed by connection system


10


′.




To remove connection system


10


′, a prybar or other suitable tool is used to engage notch


52


defined in abutment section


14


′ to pull up on connection system


10


′ thereby “popping out” connection section


10


′.





FIG. 6

illustrates an interior of a dragline tooth used with dragline buckets that are generally very large. Dragline tooth


60


includes a web


61


that extends through the center of the tooth. A notch


37


′ is defined within the web and serves as interference portion


36


for dragline tooth


60


.

FIG. 7

illustrates a connection system


10


′ coupling a dragline tooth


60


to an adaptor


31


′. Of course, connection system


10


may be used if it is so desired. The method of inserting and disengaging connection system


10


,


10


′ with a dragline tooth


60


and adaptor


31


′ is substantially the same as previously described.





FIG. 9

illustrates an alternative embodiment of an adaptor


31


′ wherein nose


44


′ is shorter and does not extend fully into tooth


30


and thus a slight space is defined between nose


44


′ and tooth


30


when tooth


30


is coupled to adaptor


31


with either connection system


10


or connection system


10


′. In this embodiment, flanges


70


are provided at the rear of tooth


30


′ and engage flanges


71


on the sides of adaptor


31


when tooth


30


′ is coupled to adaptor


31


. This allows for transmission of lateral forces between tooth


30


′ and adaptor


31


during use.




With reference to

FIG. 10

, a connection system


100


includes a biasing portion


101


and a locking portion


102


. Preferably, the biasing portion includes a biasing section


103


and an abutment section


104


. The locking portion preferably includes a locking section


105


and an interference section


106


. Preferably, the abutment section consists of elastomeric materials such as rubber, plastic, etc. Preferably the locking section and interference section consist of a non-elastomeric material, most preferably metal. Preferably, the interference section includes an interference cavity


107


defined on an upper surface


108


. Biasing portion


101


and interference section


106


are preferably coupled to one another with a hinge


110


. The biasing portion includes at least one biasing pin


111


protruding from a rear wall


112


. Additionally, the locking section includes at least one corresponding biasing plunger


113


that is preferably biased with a spring


114


. Preferably, there are three biasing pins and three corresponding biasing plungers arranged alongside one another. Each biasing pin and each biasing plunger preferably include o-rings


115


,


116


to help prevent entry of dirt or sand or similar substances to enter the corresponding cavities that contain the biasing pins and plungers.




In use, the locking section is placed within a cavity for receiving the connection system and the interference section of the locking portion is placed underneath it. The biasing portion is then placed within the cavity that receives the connection system such that the biasing pins engage their corresponding biasing plungers. The distal ends of the biasing pins engage a corresponding detent


117


while the locking section engages a similar detent


118


. A nose or protrusion


119


of the tooth engages interference cavity


107


. Thus, the connection system connects the tooth to the adaptor due to the interference fit provided by the connection system.




If one wishes to remove the connection system, a removal cavity


120


is preferably provided to help in pulling the biasing portion up and out of the receiving cavity. By applying a force within the removal cavity, the biasing pins may be forced against the spring loaded biasing plungers and allowed to “pop out” of detents


117


, thus allowing for removal of the connection system.




Accordingly, the present invention provides a connection system that securely couples two items together that are configured to receive such a connection system. The connection system is ideally suited for connecting teeth to adaptors on excavating buckets and the like. The connection system eliminates the need for a hole within the teeth for receiving a pin since a pin is no longer needed. Since the connection system is self-tightening, less work is required to fabricate the teeth because tolerances are improved. The connection system prevents dirt from entering between the tooth and the adaptor thereby preventing wear of the adaptor and thus lowering the frequency, and possibly even eliminating, the need for replacing the adaptor.




Furthermore, the tightness of fit and the full surface contact along the sides and bottom of the tooth over the nose prevent relative motion, thereby preventing wear on the surface between the tooth and the adaptor, which also greatly extends the life of the adaptor. The tooth is virtually immovable on the adaptor and thus prevents wear on the interior of the tooth as well as the nose of the adaptor, and additionally promotes good transfer of forces between the tooth and the adaptor and thereby to the bucket on which the adaptor is attached. Furthermore, the tightness of fit is achieved by not requiring tight manufacturing tolerances because any play between the adaptor and the tooth is taken up by biasing the locking section further under the interference section.




Because the connection system includes portions made of elastomeric material, preferably rubber, the connection system biases the locking section under the interference section to thereby create a tight “wedged” lock between the two angled surfaces. If the tooth encounters a large object, and thus is subjected to heavy force, the tooth may simply move back toward the adaptor and the connection would become tighter by compressing the biasing portion.




Since a hammer is not required to remove the connection system, the chance of injury is minimized.




The connection system is also reusable and thus eliminates the cost of replacing pins associated with each changing of a tooth.




Although the invention has been described with reference to specific exemplary embodiments, it will be appreciated that it is intended to cover all modifications and equivalents within the scope of the appended claims. For example, the connection system has been described as having several portions connected, which is not required. Additionally, the receiving portion surface on which the connection system rests may be angled to provide the wedging effect. Also, other arrangements may be used to provide the interference fit between the tooth and the connection system.



Claims
  • 1. A bucket for an excavation apparatus, the bucket comprising a bucket body having a lip running longitudinally along a bottom front portion of the bucket body, at least one adaptor coupled to the lip and including a receiving portion defined therein that includes an abutment wall, and a tooth connected to the adaptor with a connection system and including an interference portion, the connection system comprising:a. a biasing portion adjacent the abutment wall when the connection system is in use, the biasing portion including at least one biasing pin protruding from a rear wall; and b. a locking portion adjacent the biasing portion, the locking portion including a locking section and an interference section that engages the interference portion when the connection system is in use, the locking section and interference section being capable of movement relative to one another, the locking section including at least one biasing plunger that engages a corresponding one of the at least one biasing pin when the connection system is in use.
  • 2. The bucket of claim 1 wherein the locking section and the interference section are separate pieces that are adjacent one another.
  • 3. The bucket of claim 2 wherein the locking section is connected to the biasing portion via a hinge.
  • 4. The bucket of claim 2 wherein the interference section and the locking section each include an angled surface, the respective angled surfaces being placed adjacent one another.
  • 5. The bucket of claim 1 wherein the biasing portion includes at least three biasing pins and the locking section includes at least three biasing plungers.
  • 6. The bucket claim 1 wherein the interference portion comprises a notch defined within the tooth and the interference section comprises a projection.
  • 7. The bucket of claim 6 wherein the locking section includes an indentation defined within a top surface that engages an edge of the tooth.
  • 8. Excavating apparatus comprising at least one bucket, the bucket comprising a bucket body having a lip running longitudinally along a bottom front portion of the bucket body, at least one adaptor coupled to the lip and including a receiving portion defined therein that includes an abutment wall, and a tooth connected to the adaptor with a connection system and including an interference portion, the connection system comprising:a. a biasing portion adjacent the abutment wall when the connection system is in use, the biasing portion including at least one biasing pin protruding from a rear wall; and b. a locking portion adjacent the biasing portion, the locking portion including a locking section and an interference section that engages the interference portion when the connection system is in use, the locking section and interference section being capable of movement relative to one another, the locking section including at least one biasing plunger that engages a corresponding one of the at least one biasing pin when the connection system is in use.
  • 9. The excavating apparatus of claim 8 wherein the locking portion and the interference section are separate pieces.
  • 10. The excavating apparatus of claim 9 wherein the locking portion is connected to the biasing portion via a hinge.
  • 11. The excavating apparatus of claim 10 wherein the interference portion comprises a notch defined within the tooth and the interference section comprises a projection.
  • 12. The excavating apparatus of claim 9 wherein the interference section and the locking section each include an angled surface, the respective angled surfaces being placed adjacent one another.
  • 13. The excavating apparatus of claim 9 wherein the biasing portion includes at least three biasing pins and the locking section includes at least three biasing plungers.
  • 14. The excavating apparatus of claim 9 wherein the interference portion comprises a notch defined within the tooth and the interference section comprises a projection.
  • 15. The excavating apparatus of claim 14 wherein the locking section includes an indentation defined within a top surface that engages an edge of the tooth.
Parent Case Info

This application is a divisional application of U.S. patent application Ser. No. 09/704,297, filed Nov. 11, 2000, now U.S. Pat. No. 6,393,738, which is a continuation-in-part of U.S. patent application Ser. No. 09/329,989, filed Jun. 9, 1999, now U.S. Pat. No. 6,216,368, which claims benefit of U.S. provisional application Ser. No. 60/089,357,filed Jun. 15, 1998, the disclosures of which are incorporated herein by reference for all purposes.

US Referenced Citations (5)
Number Name Date Kind
4811505 Emrich Mar 1989 A
4823487 Robinson Apr 1989 A
5423138 Livesay et al. Jun 1995 A
5561925 Livesay Oct 1996 A
5926982 Keech et al. Jul 1999 A
Provisional Applications (1)
Number Date Country
60/089357 Jun 1998 US
Continuation in Parts (1)
Number Date Country
Parent 09/329989 Jun 1999 US
Child 09/704297 US