RETENTION MECHANISM FOR GROUND ENGAGING TOOLS

A retention mechanism for connecting a tip to an adapter may have a main retainer, a center pin, and a center pin clip attachable to the center pin. The main retainer may have a retainer body, a non-circular thru hole extending along a central axis, and a male thread around an outer surface of the main retainer. The male thread may engage a female thread in a transverse thru hole in the tip. The center pin may have a profile matching that of the non-circular thru hole of the main retainer. The non-circular thru hole of the main retainer may align with a non-circular blind hole in the adapter when in its fully engaged position. The center pin may be inserted into the non-circular thru hole of the main retainer with a distal end of the center pin positioned in the non-circular blind hole in the adapter.

TECHNICAL FIELD

The present disclosure relates generally to retention mechanisms for ground engaging tools and, more particularly, to retention mechanisms for removably attaching tooth assemblies with replaceable tip and adapter systems to edges of ground engaging implements on various earth-working machines.

BACKGROUND

Earth-working machines, for example, excavators, wheel loaders, hydraulic mining shovels, cable shovels, bucket wheels, bulldozers, and draglines are generally used for digging or ripping into the earth or rock and/or for moving loosened work material from one place to another on a worksite. Such earth-working machines typically include earth-working implements, such as a bucket or a blade, for excavating or moving the work material. These earth-working implements are subjected to extreme wear due to abrasion caused by or impacts of the work material on the implements.

To facilitate the earth-moving process and to prolong the useful life of the implement, a plurality of tip assemblies may be placed along a base edge of a working implement (e.g., bucket or blade) and may be attached to a surface of the implement. The tip assemblies project forward from the base edge and form a first point of contact with and penetration into the work material. Thus the abrasion and impacts caused by the work material tend to cause wear on the tip assemblies instead of on the base edge, reducing the amount of wear on the base edge. With this arrangement, the tip assemblies may be subjected to the wear and/or breakage caused by repetitive engagement with the work material. Periodically, the tip assemblies must be replaced, but the implement may remain useable through multiple cycles of replacement tip assemblies. Depending on the variety of uses and work materials for the equipment, it may also be desirable to change the type and/or shape of the tip assemblies to most effectively utilize the implement.

Installation and replacement of the tip assemblies may be facilitated by providing the tip assemblies with a variety of retention systems. For example, an adapter may be attached to the base edge of the implement. The adapter may be welded, bolted, or otherwise secured to the base edge. A ground engaging tip may be attached to the adapter using a retention mechanism that facilitates installation and/or removal of the tip to/from the adapter.

One example of a retention mechanism is disclosed in U.S. Pat. No. 6,052,927 to Pippins issued Apr. 25, 2000 (“the '927 patent”). The disclosed retention mechanism includes a tooth assembly having an adapter fitted with a removable tooth. The tooth is mounted on an adapter nose of the adapter by means of a pair of tooth bolts, each extending through a bolt opening in opposite side walls of the tooth and threaded in an internally-threaded insert seated in an insert cavity extending into opposite sides of the adapter nose. Each internally-threaded insert includes an internally-threaded insert bore, extending through a tapered, rounded insert body which terminates in an insert shoulder having a straight shoulder edge. The respective oppositely-disposed insert cavities are also tapered and shaped to define a cavity shoulder, which engages the insert shoulder, and an internal peripheral surface, which engages the insert body. Accordingly, the insert cavities of the adapter nose removably receive the internally-threaded inserts and prevent the inserts from rotating when the tooth bolts are inserted through the bolt openings in the opposite side walls of the tooth, threadedly engaged with the internally-threaded inserts, and tightened.

Many problems and/or disadvantages still exist with known retention mechanisms such as the retention mechanism of the Pippins. For example, the system described in Pippins may require complex machining operations or difficult to cast parts, resulting in a number of expensive parts that may be difficult to uninstall for replacement of worn parts after a machine using the retention mechanism has been operating under severe environmental conditions, and may lack the desired strength characteristics for heavy earth moving applications. Various embodiments of the present disclosure may solve one or more of the problems and/or disadvantages.

SUMMARY

In one aspect, the present disclosure is directed to retention mechanism for connecting a ground engaging tip to an adapter. The retention mechanism may include a main retainer, a center pin, and a center pin clip attachable to the center pin. The main retainer may include a retainer body extending from a retainer proximal end to a retainer distal end. The main retainer may include a non-circular thru hole extending along a central axis of the main retainer. The main retainer may also include a male thread on an outer surface of the main retainer. The male thread may be configured to threadedly engage a female thread in a transverse thru hole in the tip. The center pin may include a non-circular outer profile that matches the profile of the non-circular thru hole of the main retainer. The non-circular thru hole of the main retainer may be configured to be aligned with a non-circular blind hole in the adapter when the main retainer is in its fully engaged position. The center pin may be configured to be inserted into the non-circular thru hole of the main retainer with a distal end of the center pin positioned in the non-circular blind hole in the adapter.

In another aspect, this disclosure is directed to a tip assembly. The tip assembly may include an adapter configured to be fixed to a work implement. The tip assembly may include a tip configured to be mounted on the adapter. The tip assembly may also include a retention mechanism. The adapter may include a retainer opening extending into a nose of the adapter in a direction transverse to a longitudinal axis of the adapter. The adapter may also include a blind hole with a non-circular cross-section extending further into the nose from an inner bottom surface of the retainer opening. The tip may include a nose cavity configured to receive the nose of the adapter. The tip may also include a transverse thru hole extending through a lateral side wall of the tip transverse to the longitudinal axis. The transverse thru hole may be in communication with the nose cavity and may include a female thread. The retention mechanism may include a main retainer, a center pin, and a center pin clip attachable to the center pin. The main retainer may include a retainer body extending from a retainer proximal end to a retainer distal end. The main retainer may also include a non-circular thru hole extending along a central axis of the main retainer. Further, the main retainer may include a male thread on an outer surface of the main retainer, the male thread being configured to threadedly engage the female thread in a transverse thru hole. The center pin may include a non-circular outer profile that matches the profile of the non-circular thru hole of the main retainer. The non-circular thru hole of the main retainer may be configured to be aligned with a non-circular blind hole in the adapter when the main retainer is in its fully engaged position. The center pin may be configured to be inserted into the non-circular thru hole of the main retainer with a distal end of the center pin positioned in the non-circular blind hole in the adapter.

In another aspect this disclosure is directed to a tip assembly, The tip assembly may include a tip configured to be mounted on an adapter and a retention mechanism. The tip may include a nose cavity configured to receive a nose of the adapter. The tip may also include a transverse thru hole extending through a lateral side wall of the tip transverse to the longitudinal axis. The transverse thru hole may be in communication with the nose cavity. The retention mechanism may include a main retainer, a center pin, and a center pin clip. The main retainer may include a retainer body extending from a retainer proximal end to a retainer distal end. The main retainer may also include a non-circular thru hole extending along a central axis of the main retainer. Further, the main retainer may include a detent on an inner wall of the thru hole adjacent the retainer proximal end. The main retainer may also include a threaded outer surface of the retainer body configured to engage with a thread in the transverse thru hole. The center pin may include a non-circular outer profile that matches a profile of the non-circular thru hole of the main retainer. The center pin clip may be attachable to the center pin and may include a protrusion on an outer surface of the center pin clip. When the main retainer is in its fully engaged position, the non-circular thru hole of the main retainer may be configured to be aligned with a blind hole in the adapter, the center pin may be configured to be inserted into the non-circular thru hole of the main retainer with a distal end of the center pin positioned in the blind hole in the adapter, and the protrusion on the center pin clip is configured to engage with the detent.

DETAILED DESCRIPTION

FIG.1illustrates an exemplary work implement10for a bottom wearing application, such as a loader machine application. As illustrated in the exemplary embodiment ofFIG.1, the work implement10may be a bucket12, which may include a pair of oppositely-disposed arms14on which corresponding corner guards16may be mounted. Bucket12may also include a plurality of ground-engaging tip assemblies20mounted along a base edge22with edge protector assemblies18interposed between the tip assemblies20and secured along the base edge22of the bucket12.

FIG.2illustrates another exemplary work implement30for a top-wearing application, such as an excavator application. As illustrated in the exemplary embodiment ofFIG.2, work implement30may take the form of an excavator bucket32. Bucket32may include a pair of oppositely-disposed arms34on which corresponding corner guards36may be mounted. Bucket32may include a plurality of tip assemblies20mounted along a base edge38. Work implement30may also include one or more edge protector assemblies18interposed between tip assemblies20, with edge protector assemblies18and tip assemblies20being secured along base edge38of the bucket32. Although exemplary work implements10and30have been illustrated inFIGS.1and2, it is contemplated that work implements of other shapes and sizes may also include tip assemblies20attached to respective base edges of the work implements.

Various embodiments of tip assemblies may be implemented in bottom wearing or top wearing applications. Although a particular tip assembly or component embodiment may be described with respect to a particular bottom wearing or top wearing application, it is to be understood that the tip assemblies are not limited to a particular type of application and may be interchangeable between implements of various applications. Further, although bottom wearing and top wearing applications have been described above, it is to be understood that the disclosed embodiments are not limited to the described applications. Rather, the disclosed embodiments may be used on implements used in other types of applications (e.g., front wearing applications, end-wearing applications, or any other applications for which such implements may be used).

FIG.3is an exploded view illustrating components of an exemplary tip assembly20. Tip assembly20may be used on multiple types of ground engaging implements that have a base edge, such as base edge22or38(seeFIGS.1,2). Tip assembly20may include an adapter42configured for attachment to a base edge, such as the base edge22or38of the implement10or30, respectively, and a ground engaging tip44configured for attachment to the adapter42. The tip assembly20may further include a retention mechanism50for securing the ground engaging tip44to the adapter42. The retention mechanism50may comprise a center pin52, one or more center pin clips54, and one or more main retainers56. Adapter42may include retainer opening60configured to receive main retainer56. In some exemplary embodiments, adapter42may include a retainer opening60on either side of adapter42to receive a pair of main retainers56of retention mechanisms50from opposite sides of the adapter42. Tip44may include one or more transverse thru holes70(one transverse thru hole70shown inFIG.3). In some exemplary embodiments, tip44may include transverse thru holes70on either side of tip44to receive main retainers56of retention mechanisms50from opposite sides of the tip44. Center pin clip54may be attachable to center pin52, which may be insertable into main retainer56. Once attached to adapter42, tip44may extend outwardly from base edge22or38of work implement10or30, respectively, for initial engagement with work material. As illustrated inFIG.3, adapter42and tip44may have a coextensive longitudinal axis201that may pass through a cross-sectional center of the tip44and the adapter42.

Adapter42may extend from adapter front end82to adapter rear end84. Adapter42may include adapter rear portion86and nose88. Adapter rear portion86may include strap wall90, upper strap92and lower strap94. In some exemplary embodiments, upper strap92may be disposed at a position higher than lower strap94relative to a direction of gravity. It is contemplated however that in some embodiments, upper strap92may be disposed at a position lower than lower strap94. Accordingly, the terms upper and lower should be understood as merely defining positions relative to each other and not necessarily relative to a direction of gravity. Upper strap92may extend from the rear face96of strap wall90in a direction from adapter front end82towards adapter rear end84. Similarly lower strap94may extend from the rear face96of strap wall90in a direction from adapter front end82towards adapter rear end84. Upper strap92and lower strap94may have the same or different lengths, weights, and/or shapes. Upper strap92and lower strap94may be spaced apart from each other by gap98that may be configured to receive base edge22or38of work implement10or30, respectively. Base edge22or38of work implement10or30, respectively, when inserted into gap98may abut against rear face96of strap wall90. Adapter42may be attached to base edge22or38of work implement10or30, respectively, using fasteners, such as, bolts, nuts, screws, rivets, and/or using welding, brazing, or any other method of attachment.

FIGS.4-6depict various views of the nose88of adapter42(seeFIG.3) As depicted inFIGS.4-6, nose88of adapter42may be an asymmetrical nose having a bottom surface315and a top surface330differently shaped from the bottom surface315. Nose88may also include opposing side surfaces335, a front surface340, and a rear edge380that may abut on a front face100(seeFIG.3) of strap wall90(seeFIG.3). The rear edge380may coincide with a plane disposed generally perpendicular to the longitudinal axis201(seeFIG.3) and intersecting with the adapter42at a location at which the adapter42has its largest cross-sectional area (e.g., at front face100of strap wall90). Rear edge380may abut on front face100of strap wall90.

The bottom surface315may comprise a generally planar front portion316disposed proximate to and extending rearwardly (e.g., in a direction from adapter front end82toward adapter rear end84ofFIG.3) from the front surface340, and a rear portion317extending rearwardly from the front portion316toward the rear edge380of nose88. The bottom surface315may provide a stable surface to act as a contact area when the tip44is subjected to an upward load, while reducing wear on the tip assembly20(seeFIGS.1-3). The top surface330of nose88may be configured to support the ground engaging tip44(seeFIG.3) during use of the implement10or30(seeFIGS.1-2) and to facilitate retention of the ground engaging tip44on the nose88when bearing a load of work material. The top surface330may include a plurality of surfaces as explained below.

As depicted inFIG.5, the nose88may include surfaces such as a generally planar front-side surface305disposed proximate to the front surface340, a generally planar intermediate-side surface345extending rearwardly (e.g., in a direction from adapter front end82towards adapter rear end84ofFIG.3) from the front-side surface305, and a rear-side surface350extending rearwardly from the intermediate-side surface345to the rear edge380of the nose88. The front surface340of the nose88may be planar as shown inFIGS.4-6. In other embodiments (not shown), it may include a degree of curvature. As depicted inFIG.4, front surface340may be hexagonally shaped comprising a bottom edge341, opposing side edges342oriented at about 90° with respect to the bottom edge341, a top horizontal edge343oriented about parallel to the bottom edge341, and opposing top sloping edges344connecting the top horizontal edge343to the side edges342. It is contemplated, however, that in some exemplary embodiments, front surface340may have a triangular, square, rectangular, circular, elliptical, polygonal, or any other shape.

As depicted inFIG.6, nose88may also include a bottom rib320of the bottom surface315. The bottom rib320of the bottom surface315may comprise a generally planar front rib portion321inclined downwardly (e.g., in a direction from top surface330towards bottom surface315) relative to the bottom surface315, and a generally planar rear rib portion322inclined downwardly relative to the front rib portion321, between opposing rib side surfaces. The bottom rib320may provide increased stability during side loading and increased wedging during push-on loading.

The side surfaces335of nose88may be generally planar and extend between the bottom surface315and the top surface330. As depicted inFIG.5, the side surfaces335(seeFIG.4) may comprise a generally planar front side surface331disposed proximate to the front surface340, a generally planar intermediate side surface332extending rearwardly from the front side surface331, and a rear side surface333extending rearwardly from the intermediate side surface332to the rear edge380of the nose88.

Side surfaces335may include a retainer opening60. A central axis203(seeFIG.4) of the retainer opening60may extend substantially perpendicular (or transverse) to the longitudinal axis201(seeFIGS.3and5) of the adapter42. Retainer opening60may extend partway into a thickness of the nose88and may be configured to receive at least a portion of the main retainer56(seeFIG.35). Retainer opening60may comprise outer angled surface390, inner side surface391, and inner bottom surface392, as depicted inFIG.4. Outer angled surface390may provide an angled connection (such as a bevel) between side surface335and inner side surface391of retainer opening60. Outer angled surface390may extend around an outer perimeter of inner side surface391of retainer opening60. Outer angled surface390may further comprise a partially or fully rounded connection between the inner side surface391and side surface335. Retainer opening60may further comprise inner side surface391, as depicted inFIG.4. Inner side surface391may have a generally cylindrical shape. Inner side surface391may be located between outer angled surfaces390and inner bottom surface392. Inner side surface391may define a perimeter of retainer opening60into which main retainer56may be inserted. An outer surface246of the main retainer56may be spaced apart from inner side surface391(seeFIG.35) when the main retainer is in its locked position. Inner bottom surface392may be disposed generally perpendicular to inner side surface391and to central axis203.

FIG.7illustrates features on one side of the adapter nose88, including the retainer opening60extending into the nose88or102of the adapter42in a direction transverse to a central longitudinal axis201(seeFIG.5) of the adapter42. As illustrated inFIG.7, the retainer opening60may include a blind hole106with a non-circular cross-section (the exemplary embodiment of the blind hole106shown inFIG.7has a substantially square cross-section) extending further into the nose88of the adapter42from the inner bottom surface392of the retainer opening60. Various alternative embodiments may include other non-circular profiles, such a triangular profile, rectangular profile, or a polygona profile for the blind hole106.

Although nose88has been described above as an asymmetrical nose because top surface330includes features different from bottom surface315, it is contemplated that in some exemplary embodiments, adapter42may have a symmetrical nose that may take the place of nose88ofFIG.3.FIGS.8-10depict various views of a symmetrical nose102of adapter42(seeFIG.3) As depicted inFIGS.8-10, nose102of adapter42may be a symmetrical nose having a bottom surface315that may be similarly shaped as a top surface330, opposing side surfaces335, a front surface340, and a rear edge380that may abut on a front face100(seeFIG.3) of strap wall90(seeFIG.3). The rear edge380may coincide with a plane disposed generally perpendicular to the longitudinal axis201(seeFIG.3) and intersecting with the adapter42at a location at which the adapter42has its largest cross-sectional area (e.g., at front face100of strap wall90). Rear edge380may abut on front face100of strap wall90.

As depicted inFIG.9, top surface330of the nose102may include surfaces such as a generally planar front-side surface305disposed proximate to the front surface340, a generally planar intermediate-side surface345extending rearwardly (e.g., in a direction from adapter front end82towards adapter rear end84ofFIG.3) from the front-side surface305, and a rear-side surface350extending rearwardly from the intermediate-side surface345to the rear edge380of the nose102. Like the top surface330, the bottom surface315of nose102may also comprise a generally planar front-side surface305disposed proximate to the front surface340, a generally planar intermediate-side surface345extending rearwardly (e.g., in a direction from adapter front end82towards adapter rear end84ofFIG.3) from the front-side surface305, and a rear-side surface350extending rearwardly from the intermediate-side surface345to the rear edge380of the nose102.

The front surface340of the nose102may be planar as shown inFIGS.8-10. In other embodiments (not shown), it may include a degree of curvature. As depicted inFIG.8, front surface340may be octagonally shaped comprising opposing top and bottom edges341, opposing side edges342oriented at about 90° with respect to opposing top and bottom edges341, a top horizontal edge343oriented about parallel to the bottom horizontal edge343, opposing sloping edges344connecting the top horizontal edge343to the side edges342, and opposing sloping edges344connecting the bottom horizontal edge343to the side edges342. It is contemplated, however, that in some exemplary embodiments, front surface340of symmetrical nose102may have a square, rectangular, circular, elliptical, polygonal, or any other shape.

The side surfaces335of nose102may be generally planar and extend between the bottom surface315and the top surface330. As depicted inFIG.9, the side surfaces335(seeFIG.8) may comprise a generally planar front side surface331disposed proximate to the front surface340, a generally planar intermediate side surface332extending rearwardly from the front side surface331, and a rear side surface333extending rearwardly from the intermediate side surface332to the rear edge380of the nose102. Side surfaces335of nose102may include a retainer opening60that may be similar to the retainer opening60described above in connection with nose88.

FIG.11depicts ground engaging tip44. The ground engaging tip44may be generally wedge-shaped and have a rear edge420that may be configured to abut on front face100(seeFIG.3) of strap wall90(seeFIG.3) of nose88(seeFIGS.4-6) or symmetrical nose102(seeFIG.8-10). The tip44may have a top outer surface425extending forward (e.g., in a direction from adapter rear end84towards adapter front end82ofFIG.3) from a top of the rear edge420, and a bottom outer surface430extending forward from a bottom of the rear edge420of ground engaging tip44. The top outer surface425and the bottom outer surface430may be angled toward each other such that the top outer surface425and the bottom outer surface430converge at a front edge421at the front of the ground engaging tip44. A nose cavity440may be defined within the ground engaging tip44. Nose cavity440may extend from rear edge420into tip44in a forward direction (e.g., direction from rear edge420toward front edge421). Nose cavity440may define a pair of lateral side walls452,454that may extend between top outer surface425and bottom outer surface430. Lateral side walls452,454of tip44may include lateral outer surfaces435extending between the top outer surface425and the bottom outer surface430on either side of ground engaging tip44with the transverse thru hole70passing through each of lateral side walls452,454for installation of the center pin52, center pin clip54, and main retainer56(seeFIG.3).

As depicted inFIG.11, lateral outer surfaces435of ground engaging tip44may include transverse thru holes70in one or both of lateral side walls452,454for receiving the main retainer56(seeFIG.3) when ground engaging tip44is installed on the adapter42(seeFIG.3). Transverse thru hole70may be a thru-hole passing through one or both of lateral side walls452and454such that transverse thru hole70is in communication with nose cavity440. One of the transverse thru holes70may be disposed on the external surface508of the tip ear pad506and an opposite end of the transverse thru hole70may be disposed on the side inner surface449(seeFIG.12) of the nose cavity440. When tip44is attached to adapter42, transverse thru hole70may be aligned with retainer opening60in adapter42. In some exemplary embodiments, ground engaging tip44may include the transverse thru hole70on both lateral side walls452,454, as depicted inFIGS.11,12. In other exemplary embodiments, tip44may include the transverse thru hole70on only one of the lateral side walls452or454. As illustrated inFIG.11, the transverse thru hole70may comprise a diameter D and an opening depth OD through thickness T of lateral side wall452or454. Opening depth OD may be the same depth as ground engaging tip thickness T of lateral side wall452or454or up to three times the depth of ground engaging tip thickness T. In one exemplary embodiment, as depicted inFIG.11, opening depth OD may be twice the depth of ground engaging tip thickness T. Diameter D of the transverse thru hole70may range between 40 percent to 100 percent of height H, as depicted inFIG.12. In one exemplary embodiment as depicted inFIG.11andFIG.12, diameter D of the transverse thru hole70may be sixty percent of height H.

Ground engaging tip44may be configured to be received onto the nose88(seeFIG.4) or nose102(seeFIG.8). As illustrated inFIG.12, a nose cavity440may be defined within the ground engaging tip44. In some exemplary embodiments, the nose cavity440of tip44may be asymmetrical and may have a complimentary configuration to receive the nose88. For example, asymmetrical nose cavity440may include a bottom inner surface445, a top inner surface447, a pair of opposing side inner surfaces449, and a front inner surface450that may match with corresponding outer surfaces of asymmetrical nose88to allow asymmetrical nose88to be received in asymmetrical nose cavity440. In some exemplary embodiments, the nose cavity440may be symmetrical and may have a complimentary configuration to receive the symmetrical nose102. For example, the bottom inner surface445, top inner surface447, pair of opposing side inner surfaces449, and front inner surface450may have shapes and dimensions that may match with corresponding outer surfaces of symmetrical nose102to allow symmetrical nose102to be received in symmetrical nose cavity440.

As illustrated inFIG.11, tip44may include a tip ear pad506that may be formed (e.g., by casting) on at least one lateral outer surface435. Tip ear pad506may include tip ear pad front surface504that may extend rearwardly (e.g., in a direction from tip front edge421toward tip rear edge420). Tip ear pad front surface504may be inclined outwardly relative to lateral outer surface435in a transverse direction (e.g., direction generally perpendicular to longitudinal axis201and going from lateral side wall454towards lateral side wall452). Tip ear pad506may also include external surface508of the tip ear pad506. External surface508may extend rearwardly from tip ear pad front surface504. Tip ear pad506may include tip ear pad rear surface510that extend rearwardly from external surface508. Tip ear pad rear surface510may connect with lateral outer surface435adjacent rear edge420. Tip ear pad rear surface510may be inclined inwardly relative to lateral outer surface435in a transverse direction (e.g., direction generally perpendicular to longitudinal axis201and going from lateral side wall452towards lateral side wall454). Although specific shapes of tip44and/or nose88or102have been discussed above, it is contemplated that retention mechanism50may be used to attach tips with complementary noses having shapes, sizes, dimensions, and/or configurations different from the exemplary embodiments described above.

As discussed above, the retention mechanism50may include a center pin52.FIGS.13and14illustrate an exemplary embodiment of a center pin52extending from a proximal end212of the center pin52to a distal end216of the center pin52. Center pin52may include a head210at the proximal end212, a neck214extending from the head210towards the distal end216of the center pin52, and a shank218extending from the neck214towards the distal end216. Head210may have generally planar opposing surfaces220and222facing the proximal end212and the distal end216, respectively. Head210may have a generally circular shape with a notched portion224extending over a portion of the circumference of the head210. The notched portion224may be configured to allow a tool such as the blade of a screwdriver to be inserted under the head210for prying up on the center pin52for removal of the center pin52from the main retainer56as will be explained below.

Shank218of the center pin52may have a non-circular cross-section. In one exemplary embodiment as illustrated inFIG.13, shank218may have a square cross-section. It is contemplated, however, the shank218may have a triangular, rectangular, polygonal, or any other type of non-circular cross-section. The cross-sectional profile of the shank218may be compatible with the cross-sectional profile of the blind hole106of retainer opening60(seeFIG.7) such that shank218may be insertable into blind hole106of retainer opening60. Shank218may also include shank end portion226extending from distal end216of center pin52partway toward proximal end212. Shank end portion226may be tapered such that a cross-sectional area of shank218at distal end216may be smaller than the cross-sectional area of shank218adjacent neck214. Tapered shank end portion226may make it easier for center pin52to be inserted into main retainer56as will be described below. Neck214of center pin52may have a cross-sectional area smaller than that of shank218and head210. Thus, neck214may form a recess between the head210and the shank218.

FIG.15illustrates a perspective view of an exemplary center pin clip54. The center pin clip54may be C-shaped or U-shaped and may be configured to be installed around neck214of center pin52. In one exemplary embodiment as illustrated inFIG.15, center pin clip54may have a center wall228and legs230projecting from opposite ends of center wall228. Distal ends of legs230may be spaced apart by a gap232that may be configured to receive the neck214allowing the center pin clip54to be installed around neck214of center pin52. Distal ends of legs230may also include projections234extending towards each other such that a width w1of gap232may be smaller than a width w2(seeFIG.14) of neck214, allowing projections234to wrap around neck214helping to ensure center pin clip54may not be easily dislodged from neck214after installation. One or more of center wall228and/or legs230may include protrusions236that may be configured to engage with detents in an inner wall of the main retainer56, as will be described below.FIG.16illustrates an exemplary perspective view of center pin clip54installed on center pin52around neck214of center pin52.FIG.17illustrates a vertical cross-sectional view taken along line A-A ofFIG.16. As illustrated inFIG.17, legs230of center pin clip54may be positioned around neck214such that neck214of center pin52may be disposed between legs230of center pin clip54. Furthermore, protrusion236may extend outward in a direction away from outer surfaces of shank218of center pin52and legs230of center pin clip54. The center pin clip54may be formed from plastic, rubber, metal, or other materials with elastic properties such that the legs230of center pin clip54may be flexed apart for installation around neck214of center pin52.

FIGS.18and19illustrate perspective views of an exemplary main retainer56. Main retainer56may include a retainer body240that may extend from a retainer proximal end241to a retainer distal end243. Retainer body240of main retainer56may have a generally cylindrical outer surface246and a partial male thread248wrapped part way around the outer surface246. In one exemplary embodiment as illustrated inFIG.19, the partial male thread248may be wrapped around threaded portion242of the retainer body240. Threaded portion242may be disposed adjacent to retainer proximal end241. In alternative embodiments, the male thread248on the main retainer56may be wrapped completely around the outer surface246of the retainer body240over an angle of 360 degrees or more. Male thread248may include proximal tab portion250in the form of a helical ramp segment along a leading end of the male thread248, with a top surface252of the ramp segment being substantially coplanar with an end surface254of the main retainer56at the retainer proximal end241of the main retainer56. The top surface252of the helical ramp segment may include a marking (e.g. “LOCK”) indicating a direction of rotation of the main retainer56during installation of the main retainer56in tip44as will be described below. Retainer body240may include a non-threaded portion244disposed adjacent retainer distal end243. Non-threaded portion244may not include any portion of the male thread248. Main retainer56may include a thru hole256that may extend from adjacent retainer proximal end241to retainer distal end243of main retainer56. Thru hole256may have a non-circular cross-section that may match (e.g., have a similar or identical shape as) a cross-sectional profile of shank218(seeFIGS.13,14,16,17) of center pin52and blind hole106(seeFIG.7) of retainer opening60. For example, the cross-section of thru hole256may be square, rectangular, triangular, polygonal, or may have any other shape that matches (e.g., has a similar or identical shape as) a cross-sectional profile of shank218and blind hole106such that center pin52may be insertable into thru hole256and into blind hole106. As also illustrated inFIGS.18and19, an inner wall258of thru hole256may include one or more indentations or detents260that may be configured to engage with an receive protrusions236(seeFIGS.15-17) of center pin clip54. For example, when thru hole256has a square cross-section, some or all four inner walls258of thru hole256may include one or more detents260.

FIG.20illustrates a side elevation view of the main retainer56. As illustrated inFIG.20, the helical ramp segment at the leading end of the male thread248may form a wedge shape262that may be configured to fill the gap at the entrance to a female thread wrapped at least part way around the inner circumferential surface of the transverse thru hole70passing through the lateral side wall of the tip44. This helical ramp segment may assist in blocking dirt from entering into the threadedly engaged portions of the main retainer56and the tip44during operation of the machine, thus prolonging the life of the components and making it easier to remove the main retainer when desired for replacement of parts.FIG.21illustrates a cross-sectional view along line B-B (seeFIG.18) of the main retainer56. As shown in detail inFIG.21, the non-circular profile of the center pin and the thru hole256extending along the central axis266of the main retainer56allows for thicker main retainer walls264than would be the case with a round center pin or a threaded center pin, thus providing more shear strength against forces tending to remove the tip44from the adapter nose88or102of the adapter42. As also illustrated inFIG.21, thru hole256may include a counterbore268extending into the retainer body240of the main retainer56from retainer proximal end241. As illustrated inFIG.19, counterbore268may have a generally circular shape with an inner surface270of counterbore268tapering inwards in a direction from retainer proximal end241towards retainer distal end243. Counterbore268may also include a base272that may be disposed generally perpendicular to the central axis266of the main retainer56. As also illustrated inFIG.21, detent260in thru hole256may be positioned between the base272of the counterbore and the retainer distal end243. Further, as illustrated inFIG.21, detent260may be positioned nearer to counterbore268and to retainer proximal end241as compared to retainer distal end243.

As illustrated inFIGS.3and11, tip44may include a tip ear pad506that may be formed (e.g., by casting) on at least one lateral outer surface435(seeFIG.11) of the tip44. Tip ear pad506may be configured with the transverse thru holes70passing through the lateral side wall452and/or454(seeFIG.11) of the tip44in a direction perpendicular to a coextensive central longitudinal axis201(seeFIGS.3and11) of the tip44and the adapter42when the tip44is assembled on the nose88or102of the adapter42.

FIG.22is a perspective view of the tip ear pad506looking inwardly into the nose cavity of the tip44.FIG.23is a perspective view looking outwardly from the nose cavity440of the tip44through the lateral side wall452or454of the tip44. As illustrated inFIG.22, the transverse thru hole70may include a partial female thread/ramp structure514defined only part way around an inner circumferential wall512of the transverse thru hole70through the lateral side wall452or454of the tip44(seeFIG.11). The partial female thread514may help reduce the distance between an external surface508of the tip ear pad506and the surrounding outer surface of the lateral side wall452or454of the tip44. The partial male thread248extending part way around the outer surface246of the main retainer56, as shown inFIGS.22and23, may engage with an external surface516of the female thread514as the main retainer56is threadedly engaged in the transverse thru hole70. Rotation of the main retainer56into threaded engagement with the female thread514and into a locked position may result in the partial male thread248sliding along the female thread/ramp structure514and passing underneath a portion of the partial female thread514such that an internal surface518of the female thread (seeFIG.19) forms a ledge520that prevents removal of the main retainer56in an axial direction without counter-rotating the main retainer56to unthread it from the female thread514in the transverse thru hole70through the lateral side wall452or454of the tip44.

INDUSTRIAL APPLICABILITY

The disclosed retention mechanism for ground engaging tools may be applicable to various earth-working machines, such as, for example, excavators, wheel loaders, hydraulic mining shovels, cable shovels, bucket wheels, bulldozers, and draglines. When installed, the disclosed configurations of an exemplary retention mechanism and components may provide secure and reliable attachment and detachment of ground engaging tools to and from various earth-working implements. In particular, certain configurations of the disclosed retention mechanisms may address certain issues associated with work material getting into the space around the retention mechanism and increasing friction between components of the retention mechanism and/or between the retention mechanism and a ground engaging tool. Moreover, certain configurations of the disclosed retention mechanism may increase the strength of the retention mechanism against forces that may cause separation of the tip from the adapter, improve the manufacturability of the various components, and simplify installation and removal of the tip from the adapter.

One exemplary implementation of this disclosure includes a method for removably attaching the tip44to the adapter42fixed to an earth-moving implement of an earth-working machine.FIGS.3and24-27illustrate assembly of the adapter42, tip44, and retention mechanism50, of the tip assembly20ofFIGS.1and2, according to an exemplary implementation of the present disclosure. As illustrated inFIG.24, the adapter42may include a retainer opening60extending into the nose88or102of the adapter42in a direction transverse to a longitudinal axis201(seeFIG.3) of the adapter42. As also illustrated inFIG.24, the center pin clip54may be installed on center pin52such that center wall228and legs230of center pin clip54(seeFIG.15) may abut on to neck214(seeFIG.14) of center pin52. Further, as discussed above, the retainer opening60may include a blind hole106with a non-circular cross-section extending further into the nose88or102(seeFIGS.8-10) of the adapter42from the inner bottom surface392(seeFIG.7) of the retainer opening60. The method for removably attaching the tip44to the adapter42may include positioning the nose88or102of the adapter42inside a nose cavity440(seeFIG.12) of the tip44, the nose cavity440having a longitudinal axis coextensive with the longitudinal axis201(seeFIG.3) of the adapter42. The nose88or102may be positioned inside nose cavity440such that the blind hole106(seeFIG.7) in the retainer opening60of the nose88or102of the adapter42may be axially aligned with the transverse thru hole70extending through a lateral side wall454,454(seeFIG.12) of the tip44.FIG.25illustrates an exemplary partial tip assembly20in which nose88or102of adapter42has been inserted into nose cavity440of tip44. As illustrated inFIG.25, both main retainer56and center pin52may remain outside the adapter42and tip44at this stage of the assembly.

After positioning the nose88or102of the adapter42inside the nose cavity440of the tip44, the method may include inserting a main retainer56with a non-circular thru hole256extending along a central axis of the main retainer56into the transverse thru hole70extending through the lateral side wall452or454of the tip44.FIG.26illustrates an exemplary partial tip assembly20in which nose88or102of adapter42has been inserted into nose cavity440of tip44and the main retainer56has been inserted into the transverse thru hole70. As illustrated inFIG.26, only the center pin52may remain outside the adapter42, tip44, and the main retainer56at this stage of the assembly.

FIG.28illustrates the main retainer56after insertion into the transverse thru hole70and while in an unlocked position (e.g., in a position before it has been rotated). Thus the male thread248of the main retainer56is disengaged from the female thread514in the transverse thru hole70of the tip44.FIG.29depicts a three dimensional rendering of the main retainer56after it has been inserted into the transverse thru hole70of the tip44. As illustrated inFIG.29, the non-threaded portion244of the retainer body240adjacent retainer distal end243remains disengaged from the transverse hole70in the adapter42.

FIG.30illustrates the main retainer56after insertion into the transverse thru hole70passing through the lateral side wall453,454of the tip44and while in the unlocked position. In this position, the non-circular thru hole256extending along the central axis266of the main retainer56is not aligned with the matching non-circular blind hole106of the adapter42.FIG.30illustrates the misalignment of the non-circular thru hole256with the matching non-circular blind hole106of the adapter42when the main retainer56is in an unlocked position. As seen inFIG.30, the square cross-section of the non-circular thru hole256in the main retainer56is rotated relative to the non-circular blind hole106in the adapter42. In this position, the center pin52cannot be inserted through the non-circular thru hole256of the main retainer56into the non-circular blind hole106in the adapter42.FIG.31is a cross-sectional view of a portion of the tip assembly taken along line C-C ofFIG.26. As illustrated inFIG.31, the main retainer56is disengaged from the adapter42, with the male thread248outside of the tip44.

Returning toFIG.27, assembly of the tip44onto the adapter42may further include rotating the main retainer56to threadedly engage a partial male thread248wrapped at least part way around an outer surface246of the main retainer56with a partial female thread514defined in and wrapped part way around an inner circumferential wall512of the transverse thru hole70. Rotation of the main retainer56into a locked position includes rotating the main retainer56until the non-threaded portion244of the retainer body240of the main retainer56has entered the retainer opening60in the nose88or102of the adapter42and the non-circular thru hole256of the main retainer56is aligned with the non-circular blind hole106into the nose88or102of the adapter42.

FIG.32illustrates the main retainer56in a locked position after it has been rotated. When the main retainer56is rotated, the male thread248of the main retainer56engages with the female thread514in the transverse thru hole70of the tip44.FIG.33depicts a three dimensional rendering of the main retainer56after it has been rotated into the transverse thru hole70of the adapter42.FIG.34illustrates the main retainer56after insertion into the transverse thru hole70passing through the lateral side wall453,454of the tip44and while in the locked position. As illustrated inFIG.34, in this position, the non-circular thru hole256extending along the central axis266(seeFIG.21) of the main retainer56is aligned with the matching non-circular blind hole106of the adapter42. In this position, the center pin52can be inserted through the non-circular thru hole256of the main retainer56into the non-circular blind hole106in the adapter42.

Returning toFIG.27, the method of assembly of the tip44onto the adapter42may still further include inserting a center pin52with a complementary non-circular profile through the thru hole256in the main retainer56such that the distal end216of the center pin52enters and engages with the blind hole106in the nose88or102of the adapter42to prevent the main retainer56from being unthreaded from the tip44until the center pin52is removed from the main retainer56. As discussed above, shank end portion226(seeFIG.14) of the center pin52may be tapered for ease of insertion of center pin52into the thru hole256in the main retainer56. Furthermore, when center pin52is inserted into hole256, protrusions236on center wall228and/or legs230of center pin clip54may engage with one or more detents260in thru hole256. The engagement of the protrusions236on the center pin clip54with the detents260defined in the inner walls258of the thru hole256of the main retainer56may prevent the center pin52from disengagement from the main retainer56until a prying force is exerted against an underside of the notched portion224of the head210of the center pin52(seeFIGS.13,14) in a direction away from the main retainer56.

FIG.35is a cross-sectional view of a portion of the tip assembly taken along line D-D ofFIG.27. As illustrated inFIG.35, after rotation of the main retainer56and insertion of the center pin52, the main retainer56may be engaged with the adapter42, with the male thread248between an internal surface518of the female thread514and ledge520. As also seen inFIG.35, planar surface222of the head210of the center pin52may abut on the base272of the counterbore268in the main retainer56. Furthermore, outer surface246of retainer body240of the main retainer56may be spaced apart from inner side surface391of the retainer opening60. When the nose88of the adapter42is fully engaged with the nose cavity440of the tip44, and the center pin52has been inserted through the non-circular thru hole256of the main retainer56, a distal end of the center pin52projects from the retainer distal end243of the main retainer56and extends into the blind hole106of the nose88. The matching non-circular profile of the non-circular hole256of the main retainer56, the non-circular cross-section of the center pin52, and the non-circular profile of the blind hole106in the nose88prevents the main retainer56from being rotated and unthreaded from the tip44as long as the center pin52remains installed through the main retainer56and is engaged with the blind hole106in the nose88, thus acting as an anti-ejection mechanism.

To disassemble the tip44from the adapter42, a prying tool such as the blade of a screwdriver may be inserted between head210of the center pin52and inner surface270of the counterbore268of the main retainer56to extract the center pin52from the thru hole256and the blind hole106. After the center pin52has been removed, the main retainer56may be rotated such that the male thread248of the main retainer56disengages from the female thread514in the transverse thru hole70. Counter-rotation of the main retainer56may enable removal of the main retainer56from the adapter42and tip44when removal of the tip44from the adapter42is desired for replacement of the tip44. Once the main retainer56has been fully disengaged, the main retainer56may be extracted from the thru hole256. The tip44may now be removed such that the nose88or102of the adapter42is extracted from nose cavity440of the tip44. The center pin52, the flexible center pin clip54, and the main retainer56may all be reused, if they have not been damaged, after a new tip44is installed on the adapter42.

In various exemplary implementations of a method according to this disclosure the transverse opening extending into the nose of the adapter may be one of two transverse openings extending into the nose of the adapter from each of opposite sides of the nose of the adapter in a direction transverse to the longitudinal axis of the adapter, and each of the transverse openings may include a blind hole with a non-circular cross-section extending further into the nose of the adapter from a bottom of the transverse opening. The hole extending through a side wall of the tip may be one of two holes extending through two opposite side walls of the tip in a direction transverse to the longitudinal axis of the adapter, each of the two holes being in communication with the nose cavity in the tip and aligned with one of the two transverse openings extending into the nose of the adapter on one of the opposite sides of the nose.