Lip assembly

Information

  • Patent Grant
  • 6751897
  • Patent Number
    6,751,897
  • Date Filed
    Tuesday, November 13, 2001
    24 years ago
  • Date Issued
    Tuesday, June 22, 2004
    21 years ago
  • Inventors
  • Examiners
    • Batson; Victor
    Agents
    • Townsend and Townsend and Crew LLP
Abstract
A lip assembly is disclosed. The lip assembly comprises a lip having an upper surface, a lower surface, a front portion, and a rear portion. A plurality of holes is disposed between the front portion and the rear portion. The lip also includes support members. Each support member is disposed adjacent to a hole within the plurality of holes and is positioned to inhibit movement of a tooth assembly coupled to the hole. A plurality of tooth assemblies extend away from the lip and are respectively coupled to the lip via the plurality of holes. The lip assembly may be used with an excavation bucket body.
Description




BACKGROUND OF THE INVENTION




Many large excavators are provided with bucket assemblies. The bucket assemblies can be used to remove earth, tar sand, etc. In a typical excavator, a lip is welded to an edge of a bucket body. The lip, viewed head-on or looking into the bucket, may be skewed rearwardly at its two opposite ends. Chisel-shaped excavating teeth are coupled to the lip and are used for digging. The lip can have a means for removably securing the teeth to the lip so that worn or damaged teeth can be replaced. Damaged or worn teeth should be replaced to avoid damage to the lip and the bucket body and to maintain the effectiveness of the bucket assembly.




Replacing damaged teeth is an expensive and time-consuming task. If the teeth become worn or damaged, workers must stop any excavation taking place to replace the worn or damaged teeth. Replacement teeth for excavators are relatively expensive parts that are made from relatively large quantities of hard materials such as carbon steel. The cost of the replacement teeth as well as the cost of the manpower used to replace worn or damaged teeth with replacement teeth inevitably results in increased project costs. In addition, replacing worn or damaged teeth frequently consumes the time of many workers and can result in project delays.




One factor which contributes to the increased frequency of damaged teeth is the lateral movement of the teeth during digging. During digging, the individual teeth can move from side-to-side. The lateral movement of the teeth causes them to repeatedly contact adjacent structures such as adjacent lip shrouds. This can result in increased wear on the teeth and increased stress. Consequently, frequent replacement of the teeth is needed in many instances.




Accordingly, it would be desirable to provide a lip assembly for an excavation bucket assembly which can reduce the frequency of replacing worn or damaged teeth. Embodiments of the invention are directed to this and other problems.




SUMMARY OF THE INVENTION




Embodiments of the invention are directed to lip assemblies, and in particular, lip assemblies for excavation bucket assemblies. In embodiments of the invention, tooth assemblies which are used in excavation bucket assemblies have restricted movement in a lateral direction. Contact between the tooth assemblies and other structures such as lip shrouds is reduced. This decreases the wear on the tooth assemblies and consequently increases their useful life. As a result, the frequency of replacing damaged or worn teeth is decreased in comparison to conventional excavation bucket assemblies.




One embodiment of the invention is directed to a lip assembly comprising a lip having an upper surface, a lower surface, a front portion, and a rear portion. A plurality of holes are disposed between the front portion and the rear portion, and each of the holes extends from the upper surface to the lower surface of the lip. The lip has a plurality of support members and each support member is disposed adjacent to a hole from the plurality of holes and inhibits the lateral movement of a tooth assembly coupled to the hole. The assembly also includes a plurality of tooth assemblies extending away from the lip. Each tooth assembly is respectively coupled to the lip via the plurality of holes.




Another embodiment of the invention is directed to a lip assembly comprising: (a) a U-shaped lip having (i) an upper surface, (ii) a lower surface, (iii) a front portion having projections and valleys, (iv) a rear portion, (v) a first plurality of holes disposed between the front portion and the rear portion and extending from the upper surface to the lower surface, (vi) a second plurality of holes disposed at the front portion, (vii) a plurality of ribs at the lower surface of the lip, wherein each hole of the first plurality of holes is disposed between a pair of ribs to inhibit the lateral movement of a tooth assembly disposed between the pair of ribs, and (viii) a plurality of lip shrouds respectively disposed on the projections of the front portion of the lip. The lip assembly also includes (b) a plurality of tooth assemblies extending away from the lip and respectively coupled to the lip via the first plurality of holes.




Another embodiment of the invention is directed to an excavation bucket assembly comprising: (a) an excavation bucket having a front portion, and (b) a lip assembly. The lip assembly comprises a lip having an upper surface, a lower surface, a front portion, and a rear portion. A plurality of holes is disposed between the front portion and the rear portion, and each of the holes extends from the upper surface to the lower surface of the lip. The lip has a plurality of support members and each support member is disposed adjacent to a hole from the plurality of holes and inhibits the lateral movement of a tooth assembly coupled to the hole. The lip assembly also includes a plurality of tooth assemblies extending away from the lip. Each tooth assembly is respectively coupled to the lip via the plurality of holes.




These and other embodiments are described in further detail below.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

shows a perspective view of a lip.





FIG. 2

shows a partial top view of an excavation bucket assembly including a lip assembly according to an embodiment of the invention. Stabilizing members are shown in

FIG. 2

by invisible lines.





FIG. 3

shows a partial perspective view of the underside of a lip according to an embodiment of the invention.





FIG. 4

shows a side cross-sectional view of a portion of the lip assembly along the line B—B.





FIG. 5

shows a side cross-sectional view of a portion of lip assembly shown in

FIG. 2

along the line A—A.




FIG.


6


(


a


) shows a top view of a block element.




FIG.


6


(


b


) shows a frontal view of the block element shown in FIG.


6


(


a


).





FIG. 7

shows a side and underside view of a lip assembly according to an embodiment of the invention with the stabilizing members being visible.











DESCRIPTION OF THE SPECIFIC EMBODIMENTS




Embodiments of the invention are directed to lip assemblies and excavation bucket assemblies including lip assemblies. The excavation bucket assemblies and lip assemblies according to embodiments of the invention can be used in a variety of industries including the mining and construction industries. They may be used with any suitable excavation apparatus. Examples of excavation apparatuses which use the bucket assemblies and lip assemblies include backhoes, power shovels, front-end loaders, dragline equipment, etc.




In a typical bucket assembly, a bucket body can be coupled to a lip assembly. The bucket body may have a rear wall, side walls and a bottom wall to contain an excavated material. The lip assembly can be coupled to a front portion of the bucket body to form a bucket assembly. The lip assembly may have a lip, a plurality of tooth assemblies, and a plurality of lip shrouds. The lip shrouds and the tooth assemblies can be coupled to the front portion of the lip, and the plurality of lip shrouds can be interspersed between the plurality of tooth assemblies.




The lip of the lip assembly may be of any suitable size or configuration.

FIG. 1

, for example, shows a generally U-shaped lip


20


. The lip


20


includes a first lip wing


21


(


a


) and a second lip wing


21


(


b


), as well as a front portion


23


and a rear portion


22


. The lip wings


21


(


a


),


21


(


b


) may be skewed rearwardly in relation to the front portion


23


of the lip


20


, and the distance between the lip wings


21


(


a


),


21


(


b


) may span several yards in some embodiments. An upper surface


21


(


c


) of the lip


20


is also shown in this figure, and a lower surface (not shown) is on the opposite side of the lip


20


as the upper surface


21


(


c


). Although the lip


20


may have any suitable thickness, the thickness of the lip


20


can be on the order of five inches or more (e.g., 5.5 inches). When used, the rear portion


22


of the lip


20


would typically be mounted to the front edge of an excavation bucket body (not shown) to form an excavation bucket assembly. Welding can be used to mount the rear portion


22


of the lip


20


to the front edge of the excavation bucket body.





FIG. 2

shows a portion of an excavation bucket assembly with a lip assembly


71


according to an embodiment of the invention. A front portion of a bucket body


70


is coupled to a rear portion


22


of the lip assembly


71


. Coupling may occur in any suitable manner. For example, in preferred embodiments, the lip


20


of the lip assembly


71


is welded to the front portion of the bucket body


70


.




The lip assembly


71


includes a lip


20


with a front portion


23


and a rear portion


22


. The front portion


23


includes a number of projections


23


(


a


) and valleys


23


(


b


) producing an undulating profile when viewed from the top. Tooth assemblies


60


are mounted over the valleys


23


(


b


) and between the projections


23


(


a


), while lip shrouds


36


are mounted over the projections


23


(


a


) and between the valleys


23


(


b


). The lip shrouds


36


protect the lip


20


during digging. Like the teeth


31


, the lip shrouds


36


can be replaced periodically when they become worn or damaged. Protective wearplates


35


with edge regions


35


(


a


),


35


(


b


) may be disposed on the upper surface of the lip


20


to protect the upper surface of the lip


20


. Adjacent block members


55


on opposite sides of a wearplate


35


may secure the edge regions


35


(


a


),


35


(


b


) of a wearplate


35


to the upper surface of the lip


20


. The plurality of block members


55


are respectively positioned at the ends of the adaptors


33


and the tooth assemblies


60


mounted on the lip


20


. The block members


55


can inhibit the lateral movement of the adaptors


33


and the tooth assemblies


60


and extend their working life. Most or all of the parts of the excavation bucket assembly and the lip assembly can be made of a hard metal alloy such as steel.




A first plurality of holes


37


is present between the front portion


23


and the rear portion


22


of the lip


20


. In this example, the first plurality of holes


37


consists of a generally straight line of holes. Each of the holes from the first plurality of holes


37


extends from an upper surface of the lip


20


to the lower surface of the lip


20


. Each of the holes from the first plurality of holes


37


may also have any suitable shape. For example, each of the holes from the first plurality of holes


37


in this example have an oblong shape.




A plurality of tooth assemblies


60


may be respectively coupled to the lip


20


via the first plurality of holes


37


using any type of securing mechanism. For example, a C-clamp


28


, a locking wedge


29


, and a wedge block (not shown) combination may be used to secure the tooth assembly


60


to the lip


20


. When the tooth assemblies


60


are secured to the lip


20


, the tooth assemblies


60


extend away from the lip


20


.




A second plurality of holes


38


is located at the front portion


23


of the lip


20


. Each of the holes of the second plurality of holes


38


lies between adjacent valleys


23


(


b


). The second plurality of holes


38


may be in a generally straight line, and each of the holes


38


may have any suitable shape. For example, each of the holes from the second plurality of holes


38


in this example have a circular shape.




Lip shrouds


36


are secured to the lip


20


via the second plurality of holes


38


and over the projections


23


(


a


). Each lip shroud


36


can have pair of legs which are disposed on the upper and lower surfaces of the front portion of the lip


20


when the lip shroud


36


is mounted to the lip


20


. Each lip shroud


36


may also optionally have sidewalls. The sidewalls and the legs may form a pocket in which the lip projections


23


(


a


) are received. By providing sidewalls to the lip shrouds


36


, the side-to-side movement of the lip shrouds


36


is restricted as the lip shrouds


36


conform to the shape of the respective lip projections


23


(


a


). The likelihood that the lip shrouds


36


will contact adjacent tooth assemblies


60


is reduced, thus increasing the useful life of the tooth assemblies


60


.




Each tooth assembly


60


comprises a tooth


31


. Preferably, each tooth assembly


60


comprises a tooth


31


, an adapter


33


, and an adapter shroud


32


. In these embodiments, the adapter shroud


32


covers a portion of the adapter


33


and is disposed between the adapter


33


and the tooth


31


. When they are assembled together, holes in the tooth


31


and the adapter


33


are aligned and are secured together with a connector such as a pin (not shown). If the tooth


31


becomes worn, the tooth


31


can be replaced without replacing other parts of the tooth assembly


60


. The connector can be removed along with the worn tooth and a new connector and tooth can be coupled to the adapter


33


. Suitable tooth assemblies and other components are described in U.S. Pat. No. 5,526,592 and U.S. patent application Ser. No. 09/183,478, filed Oct. 29, 1998, both of which are herein incorporated by reference in their entirety.




Any suitable number of stabilizing members


39


may be present on the lip


20


at any suitable location. In the example shown in

FIG. 2

, for example, pairs of stabilizing members


39


(


b


),


39


(


c


) are disposed between adjacent holes from the first plurality of holes


37


. Also, for each hole from the first plurality of holes


37


, a pair of stabilizing members


39


(


a


),


39


(


b


) may be disposed adjacent to, and on opposite sides of the hole. The pair of stabilizing members


39


(


a


),


39


(


b


) on opposite sides of the hole inhibit the lateral movement of a tooth assembly


60


disposed between them. Contact with other adjacent structures (e.g., the lip shrouds) is inhibited, thus decreasing the wear on the components of the tooth assemblies


60


. Furthermore, the stabilizing members


39


also provide extra support for the lip


20


itself so that the structural integrity of the lip


20


is increased in comparison to a lip without stabilizing members.




The stabilizing members


39


shown in

FIG. 2

can be characterized as parallel ribs. When the ribs are disposed on opposite sides of a tooth assembly on the lip, the movement of the tooth assembly to both sides of the tooth assembly is restricted by the presence of the ribs. Embodiments of the invention, however, are not limited to those embodiments specifically shown in the Figures. Other configurations or structures may be used to inhibit the lateral movement of the tooth assemblies. For example, in an alternative embodiment, instead of two ribs disposed between adjacent holes, only one rib can be present between adjacent holes from the first plurality of holes


37


. In an another alternative embodiment, the stabilizing member could be a single block of material (e.g., a block of steel) between adjacent holes, instead of two ribs between adjacent holes. The block of material could inhibit the lateral movement of tooth assemblies disposed on both sides of the block.




The stabilizing members


39


may have any suitable spacing or orientation. Preferably, the stabilizing members


39


are ribs which are parallel and extend in the same direction as the tooth assemblies


60


. Stabilizing members


39


which are on opposite sides of a hole from the first plurality of holes


37


are preferably spaced so that they are adapted to receive a tooth assembly


60


. For example, the spacing between two stabilizing members


39


(


a


),


39


(


b


) on opposite sides of a hole may be approximately equal to, or slightly greater than, the width of a tooth assembly


60


or an adapter


33


for a tooth assembly


60


. The spaced stabilizing members


39


(


a


),


39


(


b


) can form a slot which is configured to receive a tooth assembly


60


or the adapter


33


for the tooth assembly


60


. As shown in

FIG. 2

, the stabilizing members


39


extend from a rear portion


22


of the lip


20


towards the front portion


23


of the lip


20


. The ends of the stabilizing members


39


preferably terminate short of the front portion


23


of the lip


20


(e.g., in a central region of the lip


20


) or in the region where the adapter


33


lies. The lateral movement of each of the tooth assemblies


60


is inhibited by restricting the movement of a corresponding tooth assembly adapter


33


with the stabilizing members


39


.




The stabilizing members


39


may be formed in any suitable manner. For example, the stabilizing members


39


may be separately formed. Then, the stabilizing members


39


may be welded onto the main body of the lip


20


. In other embodiments, the stabilizing members


39


may be secured to the main body of the lip


20


via a securing mechanism such as a pin or a bolt.




The stabilizing members


39


are preferably disposed at least at the lower surface of the lip


20


. By providing the stabilizing members


39


at the lower surface of the lip


20


, the stabilizing members


39


will not obstruct the path of excavated material moving from the front portion of the lip


20


to the rear portion


22


of the lip


20


and into the bucket body


70


. Also, as previously noted, the stabilizing members


39


also inhibit the lateral movement of the tooth assemblies


60


and improve the structural integrity of the lip


20


.




A view of the underside of the lip


20


is shown in FIG.


3


.

FIG. 3

shows a lip


20


and a plurality of stabilizing members


39


. As also shown in

FIG. 2

, pairs of stabilizing members


39


(


a


),


39


(


b


) are disposed adjacent to, and on opposite sides of, respective holes from the first plurality of holes. As shown in this Figure, the thickness of the stabilizing members


39


decreases in a direction from the rear portion


22


of the lip


20


to the front portion


23


of the lip


20


.





FIG. 4

shows a side cross-sectional view of a tooth assembly


60


disposed over a lip


20


. An adapter


33


of a tooth assembly


60


is on a lip


20


. A hole


43


in the adapter


33


and a hole


37


of the first plurality of holes in the lip


20


are aligned. A mechanism such as a C-clamp and a wedge (not shown) can be used to secure the adapter


33


and the lip


20


together via the aligned holes


37


,


43


. An adapter shroud


32


lies over the adapter


33


to protect the adapter


33


, and a tooth


31


is disposed over the adapter shroud


32


. The adapter shroud


32


is disposed between the tooth


31


and the adapter


33


when the tooth assembly


60


is secured to the lip


20


and extends from the rear portion of the lip


20


to a central region of the lip


20


. A pin


34


or other securing mechanism may be used to secure the tooth


31


to the adapter shroud


32


. A stabilizing member


39


is shown on the underside of the lip


20


. The stabilizing member


39


provides structural support for the lip


39


and also inhibits the lateral movement of the tooth assembly


60


during use. A block element


55


is present at a rear end of the adaptor


33


and can inhibit the movement of the adaptor


33


.





FIG. 5

shows a side cross-sectional view of a lip shroud


36


disposed over a lip


20


. A hole


36


(


a


) in the lip shroud and a lip hole


38


from the second plurality of holes are aligned with each other. A pin (not shown) or other securing mechanism may be disposed within the aligned holes to secure the lip shroud


36


to the lip


20


. A wearplate


35


may be disposed on the upper surface of the lip


20


to protect the lip


20


from being worn or damaged by the material being excavated. A stabilizing member


39


is disposed on the underside of the lip


39


, and is disposed to a side of the wearplate


35


. A block element


55


is present at a rear end of the wearplate


35


and secures the wearplate


35


to the lip


20


.




FIG.


6


(


a


) shows a top view of a block element


55


. FIG.


6


(


b


) shows a frontal view of the block element


55


shown in FIG.


6


(


a


). The block element


55


includes a central portion


61


and two side portions


65


. Each side portion


65


is defined in part by a recess


62


that receives an edge region of an adjacent wearplate (not shown). In this regard, the height (h) of each recess


62


is generally greater than the thickness of the wearplate


35


.





FIG. 7

shows the side and underside of the lip assembly. As shown in

FIG. 7

, a number of stabilizing members


39


are present on the underside


39


of the lip assembly and inhibit the teeth


31


of the tooth assemblies from moving laterally. A wing


21


(


b


) of the lip


20


may include wing shrouds


51


and a corner shroud


53


. The shrouds


51


,


53


may be secured to the lip


20


by one or more securing mechanisms such as pins


52


. The wing shrouds


51


and the corner shroud


53


protect the wing


21


(


b


) of the lip


20


from damage during excavation. Once damaged, the various shrouds can be replaced, thus extending the useful life of the lip


20


.




The terms and expressions which have been employed herein are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described, or portions thereof, it being recognized that various modifications are possible within the scope of the invention claimed. Moreover, any one or more features of any embodiment of the invention may be combined with any one or more other features of any other embodiment of the invention, without departing from the scope of the invention.



Claims
  • 1. A lip assembly comprising:(a) a U-shaped lip having (i) an upper surface, (ii) a lower surface, (iii) a front portion having projections and valleys, (iv) a rear portion, (v) a first plurality of holes disposed between the front portion and the rear portion and extending from the upper surface to the lower surface, (vi) a second plurality of holes disposed at the front portion, (vii) a plurality of ribs at the lower surface of the lip, wherein each hole of the first plurality of holes is disposed between a pair of ribs to inhibit the lateral movement of a tooth assembly disposed between the pair of ribs, and (viii) a plurality of lip shrouds respectively disposed on the projections of the front portion of the lip; and (b) a plurality of tooth assemblies extending away from the lip and respectively coupled to the lip via the first plurality of holes.
  • 2. The lip assembly of claim 1 wherein the ribs in the pair of ribs are spaced by a distance approximately equal to the width of the tooth assembly disposed between the pair of ribs.
  • 3. The lip assembly of claim 1 wherein the ribs are welded to a main body of the lip.
  • 4. The lip assembly of claim 1 wherein the lip further comprises a plurality of block members respectively disposed at the ends of the tooth assemblies.
  • 5. A lip assembly comprising:a lip having an upper surface, a lower surface, a front portion, a rear portion, a plurality of holes disposed between the front portion and the rear portion and extending from the upper surface to the lower surface, and a plurality of support members, wherein each support member is disposed adjacent to a hole from the plurality of holes and inhibits lateral movement of a tooth assembly coupled to the hole; and a plurality of tooth assembly extending away from the lip and respectively coupled to the lip via the plurality of holes, wherein the plurality of holes is a first plurality of holes, and wherein the lip further comprises a second plurality of holes disposed at the front portion of the lip; and wherein the lip assembly further comprises: a plurality of lip shrouds on the front portion of the lip, wherein the lip shrouds in the plurality of lip shrouds are respectively coupled to the lip via the second plurality of holes, wherein the front portion includes projections and valleys, and wherein each of the second plurality of holes is disposed between adjacent valleys.
  • 6. An excavation bucket assembly comprising:(a) an excavation bucket body having a front portion; and (b) a lip assembly comprising (i) a lip having an upper surface, a lower surface, a front portion, a rear portion, a plurality of holes disposed between the front portion and the rear portion and extending from the upper surface to the lower surface, and a plurality of support members, wherein each support member is disposed adjacent to a hole from the plurality of holes and inhibits lateral movement of a tooth assembly coupled to the hole, and (ii) a plurality of tooth assemblies extending away from the lip and respectively coupled to the lip via the plurality of holes, wherein the front portion includes projections and valleys and a second plurality of holes at the front portion, and wherein each of the second plurality of holes is disposed between adjacent valleys.
  • 7. An excavation bucket assembly comprising:(a) an excavation bucket body having a front portion and (b) a lip assembly comprising (i) a lip having an upper surface, a lower surface, a front portion, a rear portion, a plurality of holes disposed between the front portion and the rear portion and extending from the upper surface to the lower surface, and a plurality of support members, wherein each support member is disposed adjacent to a hole from the plurality of holes and inhibits lateral movement of a tooth assembly coupled to the hole, and (ii) a plurality of tooth assemblies extending away from the lip and respectively coupled to the lip via the plurality of holes, and wherein the excavation bucket further comprises a plurality of block members disposed at respective ends of the tooth assemblies.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the filing date of U.S. Provisional Patent Application Nos. 60/253,356 filed Nov. 27, 2000, and 60/305,977 filed Jul. 16, 2001. Both of these applications are herein incorporated by reference in their entirety for all purposes.

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3653133 Black et al. Apr 1972 A
3762079 Lukavich et al. Oct 1973 A
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3864853 Klett et al. Feb 1975 A
3947982 Mantovani Apr 1976 A
4238896 Lanz et al. Dec 1980 A
4360981 Bierwith et al. Nov 1982 A
4413432 Bierwith Nov 1983 A
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5088214 Jones Feb 1992 A
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5417518 Bierwith May 1995 A
5526592 Bierwith Jun 1996 A
5553409 Irving Sep 1996 A
5680717 Bierwith Oct 1997 A
5852888 Cornelius Dec 1998 A
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6216368 Bierwith Apr 2001 B1
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Number Date Country
WO 9966135 Dec 1999 WO
Provisional Applications (2)
Number Date Country
60/253356 Nov 2000 US
60/305977 Jul 2001 US