WEAR MEMBER

Abstract

A wear member comprising: an upper leg having a ground engaging surface on an outer side thereof and a mounting surface on an inner side thereof, and a lower leg spaced apart from the upper leg and also having a ground engaging surface on an outer side thereof and a mounting surface on an inner side thereof, the mounting surfaces defining a mounting cavity therebetween and the legs meeting at a front portion, the upper leg defining (i) a lock aperture therein, (ii) a rear edge, and (iii) a lifting feature located adjacent to and between the lock aperture and the rear edge; the lifting feature defining (a) a front surface lower than the upper leg ground engaging surface and being inclined relative thereto, (b) a lower support surface opposite the front surface, and (c) a rear engaging surface extending between the front surface and the lower support surface and being recessed relative to the rear edge; wherein the front surface, lower support surface, and rear engaging surface provide a narrowed portion around which a lifting device may be located for relocating the wear member.

Claims

1. A wear member comprising: an upper leg having a ground engaging surface on an outer side thereof and a mounting surface on an inner side thereof, and a lower leg spaced apart from the upper leg and also having a ground engaging surface on an outer side thereof and a mounting surface on an inner side thereof, the mounting surfaces defining a mounting cavity therebetween and the legs meeting at a front portion, the upper leg defining (i) a lock aperture therein, (ii) a rear edge, and (iii) a lifting feature located adjacent to and between the lock aperture and the rear edge; the lifting feature defining (a) a front surface lower than the upper leg ground engaging surface and being inclined relative thereto, (b) a lower support surface opposite the front surface, and (c) a rear engaging surface extending between the front surface and the lower support surface and being recessed relative to the rear edge; wherein the front surface, lower support surface, and rear engaging surface provide a narrowed portion around which a lifting device may be located for relocating the wear member.

2. A wear member according to claim 1, wherein the narrowed portion is recessed relative to the upper leg ground engaging surface, the upper leg mounting surface, and the rear edge.

3. A wear member according to claim 1, wherein the front surface defines a concave shape when viewed from above such that a central portion thereof is further from the lock aperture than side portions thereof.

4. A wear member according to claim 1, wherein the lower support surface is inclined relative to the front surface, and diverges relative thereto, to provide a narrow edge near the lock aperture and an enlarged portion towards the rear edge.

5. A wear member according to claim 1, wherein the rear engaging surface defines a concave shape such that a central portion thereof is further from the rear edge than side portions thereof.

6. A wear member according to claim 1, wherein the front surface includes a wear indicator to indicate a wear level beyond which the lifting feature should not be used.

7. A wear member according to claim 1, wherein the ground engaging surfaces on the outer sides of the upper and lower legs meet at a front edge on the front portion.

8. A wear member according to claim 1, wherein the ground engaging surfaces comprise an abrasion resistant material.

9. A wear member according to claim 1, wherein the wear member comprises a shroud.

10. A wear member according to claim 9, wherein the rear engaging surface is spaced from a lip of a digging edge of an excavating machine when the shroud is mounted thereto.

11. A wear member according to claim 1, wherein the lifting feature is generally centrally located rearwards of the lock aperture.

12. A wear member according to claim 1, wherein the lifting feature defines a rounded leading edge at a junction of the lower support surface and the rear engaging surface to reduce the risk of a lifting device being damaged by the lifting feature.

13. A wear assembly comprising: (i) a base; (ii) a wear member comprising an upper leg having a ground engaging surface on an outer side thereof and a mounting surface on an inner side thereof, the upper leg defining (a) a lock aperture therein, (b) a rear edge, and (c) a lifting feature located adjacent to and between the lock aperture and the rear edge; the lifting feature being recessed relative to the ground engaging surface, the mounting surface, and the rear edge; and (iii) a lock located within the lock aperture and operable to engage with both the base and a surface of the lock aperture to secure the wear member to the base.

14. A wear assembly according to claim 13, wherein the base defines a boss upstanding from an upper surface thereof, and the lock aperture is located rearwardly of the boss, so that the lock bears against a rear surface of the boss when located within the lock aperture.

15. A wear assembly according to claim 13, wherein the lifting feature defines (a) a front surface lower than the upper leg ground engaging surface and being inclined relative thereto, (b) a lower support surface opposite the front surface, and (c) a rear engaging surface extending between the front surface and the lower support surface and being recessed relative to the rear edge.

16. A wear member comprising an outer ground engaging surface defining a lock aperture in which a lock may be located, and a lifting feature adjacent the lock aperture, the lifting feature comprising a narrowed portion recessed relative to: the outer ground engaging surface, an inner surface, and a rear edge of the wear member.

17. A wear member according to claim 16, wherein the narrowed portion is located centrally and rearward of the lock aperture.

18. A wear member according to claim 16, further comprising an upper leg defining (i) the ground engaging surface on an outer side thereof, (ii) the inner surface on an inner side thereof, and (iii) the rear edge.

19. A wear member according to claim 16, wherein the lifting feature includes a wear indicator to indicate a wear level beyond which the lifting feature should not be used.

20. A wear member according to claim 19, wherein the wear indicator comprises a geometrical shape recessed into a front surface of the lifting feature.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] These and other aspects will be apparent from the following specific description, given by way of example only, with reference will now be made to the accompanying drawings, in which:

[0033] FIG. 1 is an exploded, perspective view of a wear assembly (including a wear member and a lock) according to one embodiment of the present invention mounted on a lip of a bucket;

[0034] FIG. 2 is an enlarged perspective front view of part of the lip of FIG. 1, showing a part (a base) in more detail;

[0035] FIG. 3 is a perspective front view of the wear assembly of FIG. 1, showing the exploded parts coupled together and mounted on the lip;

[0036] FIG. 4 is a front elevation view of the wear assembly and lip of FIG. 3;

[0037] FIG. 5 is a cross sectional side elevation through line 5-5 of FIG. 4 showing the wear assembly mounted on the base in more detail;

[0038] FIG. 6 is an upper perspective view of the wear member of FIG. 4;

[0039] FIG. 7 is a front perspective view of the wear member of FIG. 1, also including a portion (a lifting feature) shown in enlarged detail;

[0040] FIG. 8 is a perspective view of the lock of FIG. 1;

[0041] FIG. 9 is a top (plan) view of the wear member of FIG. 1;

[0042] FIG. 10 is a front elevation view of the wear member of FIG. 1;

[0043] FIG. 11 is a rear elevation view of the wear member of FIG. 1;

[0044] FIG. 12 is a rear perspective view (from a high position) of the wear member of FIG. 1;

[0045] FIG. 13 is a rear perspective view (from a low position) of the wear member of FIG. 1;

[0046] FIG. 14 is a side view of the wear member of FIG. 1;

[0047] FIG. 15 is a simplified (no shading is shown) cross sectional side view (taken along line 15-15 in FIG. 10) of the wear member of FIG. 1;

[0048] FIG. 16 is an enlarged front perspective view of parts (the lifting feature and lock aperture) of the wear member of FIG. 1;

[0049] FIG. 17 is an enlarged rear perspective view of the lifting feature and lock aperture of FIG. 16;

[0050] FIG. 18 is a simplified (some shading may be omitted) cross sectional front view (taken along line 18-18 in FIG. 14) of the wear member of FIG. 1; and

[0051] FIG. 19 is an enlarged front perspective view of the lifting feature and lock aperture of the wear member of FIG. 1, showing a lifting device (a strap) looped through the lifting feature.

DETAILED DESCRIPTION OF EMBODIMENTS

[0052] Reference is first made to the Figures, which are various views of a wear assembly 10, according to one embodiment of the present invention, mounted on a lip 12 of a bucket (illustrated schematically with phantom lines 13 in FIG. 3).

[0053] The lip 12 has five forwardly projecting noses 14 mounted thereto to receive a point (or tip) (not shown). The noses 14 and points (not shown) collectively define the excavating teeth that penetrate and break up the ground ahead of the bucket. The lip 12 further comprises four bases 16, each base 16 being provided between adjacent noses 14. The noses 14 and bases 16 extend from a ramp portion 18 (FIG. 1) of the lip 12. Each base 16 is configured to accommodate a wear member 20 (according to another embodiment of the present invention) thereon. In this embodiment, the wear member 20 is a shroud.

[0054] The shroud 20 is a wear member that fits over a corresponding base 16 on the lip 12 of the excavating bucket 13, between the excavating teeth, to protect the bucket lip 12 and to direct the earthen material into the bucket 13. The shroud 20 is held in place on the base 16 by a lock 22. In this embodiment, the noses 14 and bases 16 are shown as being a cast part of the lip 12, but in other embodiments they could be attached as adapters or inserts, for example by welding or mechanical attachment. In any event, each shroud 20 is placed over a base 16 on the front edge of the lip 12 between noses 14, as illustrated in FIGS. 1 and 3.

[0055] The base 16 may comprise a harder wearing material than the remaining part of the lip 12 (or may have a hard wearing coating thereon) to resist wear caused by the shroud 20 during operation. Nevertheless, the other parts of the lip 12 are not necessarily softer than the base 16.

[0056] The wear assembly 10 comprises the shroud 20, the base 16 and the lock 22. The lock 22 (best seen in FIG. 8) is similar in design to the locks described in U.S. Pat. No. 7,536,811 and comprises two interlocking pivoting components held in place by a threaded pin (not shown) screwed into a threaded aperture 24 defined by the two interlocking components.

[0057] Referring particularly to FIGS. 2, 4, and 5, each base 16 comprises a front surface 30, an upper surface 32, side surfaces 34 and an upstanding boss 36 generally centrally located between the side surfaces 34 and protruding above the upper surface 32. The boss 36 has a rear surface 38 against which the lock 22 abuts when holding the shroud 20 in place. The base 16 and shroud 20 have complementary surfaces to allow mutually stable and secure coupling.

[0058] Front surface 30 defines a slightly convex curved shape which curves about two generally perpendicular axes. In particular, front surface 30 is curved generally about a vertical axis so that it curves rearward as it approaches each respective side surface 34; and is also curved generally about a horizontal axis so that it also curves rearward as it approaches the upper surface 32, and a lower surface (not visible in the drawings) opposite the upper surface 32.

[0059] Shroud 20 includes a front-facing wearable portion 40 (FIG. 7) and a rear-facing mounting portion 42. The shroud 20 comprises a pair of spaced apart legs 44, 46 that define a cavity 48 therebetween and that meet at a central portion 49 (best seen in FIGS. 12 and 13). The cavity 48 is generally open along its sides so that legs 44, 46 straddle the side surfaces 34 of the base 16 on the lip 12 when the shroud 20 is mounted thereon.

[0060] The upper leg 44 defines an outer wear surface 50 (also referred to as an upper ground engaging surface), and an inner coupling surface 52 (best seen in FIGS. 11 and 13). Likewise, the lower leg 46 includes an outer wear surface 54 (also referred to as a lower ground engaging surface) and an inner coupling surface 56. In the illustrated embodiment, legs 44, 46 diverge in a rearward direction to define a generally C-shaped configuration to correspond to the combined shape of the base 16 and lip portions adjacent thereto. The use of diverging legs 44, 46 also facilitates easier removal of the shroud 20 from the lip 12.

[0061] The spaced apart legs 44, 46 converge at a front of the shroud 20 to a narrow front edge 58, at the center of which is defined a lifting hook 60 to assist in mounting the shroud 20 onto the base 16.

[0062] To reduce wear during use, the outer wear surfaces 50, 54 may comprise highly abrasion resistant material, or other hard wearing material, or may include a hardened layer on an outer portion thereof.

[0063] The outer wear surface 50 defines a raised central portion 61 dimensioned to accommodate the base boss 36 in an underside thereof.

[0064] The upper leg 44 (specifically, the raised central portion 61) defines a lock aperture 62 at an upper, central location. The upper leg 44 also defines an upper leg rear edge 63 (best seen in FIGS. 7, 13, 14 and 15) extending across the width thereof (except for a central indentation (a rear engaging surface 80) described below). The raised central portion 61 does not extend to the leg rear edge 63, so that the upper leg 44 defines a narrow strip 65 therebetween. The lock aperture 62 is located significantly closer to the leg rear edge 63 than the front edge 58.

[0065] A lifting feature 64 is defined by the upper leg 44 immediately adjacent to, and rearward of, the lock aperture 62.

[0066] In a similar way to how a conventional shroud is secured to a lip, the lock 22 is pivoted into an open position and inserted into the lock aperture 62. When inserted therein, the lock 22 engages with sidewalls defining the lock aperture 62 and extends below the upper leg 44 to abut the boss rear surface 38 (FIG. 5). This prevents the shroud 20 from being pulled away from the lip 12 and base 16.

[0067] The outer wear surface 50 defines a second (upper) lifting hook 66 that is used to move the shroud 20 into position on the base 16 during installation. Typically, the lifting hooks 60, 66 will be worn away during operation of the excavating bucket 13 because these hooks 60, 66 are exposed to the earthen material being excavated.

[0068] The lock aperture 62 is defined by a front wall 67, opposing sidewalls 68a,b extending from the front wall 67, and rear wall portions 69a,b, each extending from a respective opposing sidewall 68a,b generally parallel to the front wall 67.

[0069] The lifting feature 64 comprises a narrowed central portion 70, which is recessed from the upper ground engaging surface 50 (best seen in FIG. 7, in enlarged detail and FIGS. 16 and 17). The lifting feature 64 comprises a concave (when viewed from above) front edge 72 adjacent the lock aperture 62. The front edge 72 provides an arcuate expansion of the lock aperture 62 so that the expanded lock aperture 62 can be used to access the lifting feature 64. In particular, the front edge 72 extends between the opposing rear wall portions 69a,b.

[0070] A lower support surface 76 (FIGS. 11, 13 and 15) extends backwards from the front edge 72 to a lower rear edge 78 at an angle generally parallel to the upper surface 32 but spaced therefrom to allow a lifting device (for example, a cable, a strap, or the like) to be inserted therebetween (i.e. between lower support surface 76 and upper surface 32). The lower support surface 76 is inclined relative to the upper ground engaging surface 50.

[0071] A rear engaging surface 80 (best seen in FIGS. 5, 11, 12, 13 and 17), which is arcuate when viewed from above, extends from the lower rear edge 78 to an upper edge 82. A front surface 84 (which is also concave in shape when viewed from the front) extends from the front edge 72 to the upper edge 82. The front surface 84 extends for approximately 60% of the width of the adjacent lock aperture 62. The front surface 84 defines a calibrated wear indicator 86, in the form of a recess, at a central part thereof.

[0072] The configuration of the calibrated wear indicator 86 is designed so that it functions as a wear indicator. In this embodiment, the depth and length of the recess 86 is selected based on the radius of the front edge 72, in particular, to alert a user that the front edge 72 has been worn down and presents a sharpened edge to any lifting strap or cable that would be used to engage the lifting feature 64.

[0073] In this embodiment, the calibrated recess 86 extends from the upper leg narrow strip 65 to near the front edge 72. It is expected that the front surface 84 will wear from the upper edge 82 towards the front edge 72 (i.e. the front edge 72 wearing later than the upper edge 82). In this embodiment, the calibrated recess 86 extends for 80% of the distance from the front of the upper leg narrow strip 65 to the front edge 72.

[0074] When the calibrated recess 86 is no longer visible, a user knows that it is no longer safe to use the lifting feature 64 to remove the shroud 20.

[0075] The lower support surface 76 also has a concave recess shape (relative to the adjacent parts of the inner coupling surface 52), when viewed from the rear (best seen in FIGS. 11 and 13).

[0076] The rear engaging surface 80 also has a concave recess shape (relative to the leg rear edge 63), when viewed from the top (best seen in FIGS. 9 and 12). In this embodiment, the rear engaging surface 80 is an indentation in the leg rear edge 63 at a central part thereof.

[0077] Reference is now made to FIG. 19, which illustrates a strap 90 looped through the lifting feature 64 to assist in removing the shroud 20 from the lip 12. Initially, the user inspects the calibrated wear indicator 86 to ensure that it is safe to lift the shroud 20 using the lifting feature 64. If the calibrated wear indicator 86 is visible, then the user proceeds to engage the strap 90 to the lifting feature 64.

[0078] To locate the strap 90, the user first removes the lock 22. This ensures that the lock aperture 62 is available to provide easy access to the lifting feature 64. A user couples a first end of the strap 90 to a hoist (not shown) above the shroud 20. The user then threads the second end of the strap 90 under the front edge 72, beneath the lower support surface 76, up past the rear engaging surface 80, and up towards the hoist. The user then couples the second end of the strap 90 to the hoist (not shown). The user can then operate the hoist in a conventional manner to help remove the shroud 20 from the lip 12 in a safe manner.

[0079] It will now be appreciated that this embodiment has the advantage of providing an area on a shroud that can be used to lift the shroud away from the lip when the shroud needs to be replaced. Unlike conventional lifting hooks, the lifting feature is recessed from the ground engaging surface, protected by a lock used to secure the shroud to the lip (via the base), and located rearwards of the ground engaging end of the shroud, thereby reducing any wear that the lifting feature experiences so that it can be used even after the conventional lifting hooks have all worn away. When the lock is removed, easy access is provided to the lifting feature to simplify routing a lifting device around the lifting feature. The lock aperture allows for easy removal of fines or other debris prior to routing the lifting device around the lifting feature. By locating the lifting feature to the rear of the shroud behind the lock aperture, a low stress part of the shroud is being used to define the lifting feature and very little loading is expected on this area during the working life of the shroud.

[0080] Although the wear assembly is described in terms of a shroud secured to a lip, other wear members (e.g., adapters, points, wings, runners and the like) are included in the definition of wear member. Such other wear members may be secured to bucket lips or other excavating equipment.

[0081] Various modifications may be made to the above described embodiments within the scope of the present invention. For example, the base front surface 30 could be defined as a spherical segment, by curvatures that follow different paths, or by curvatures that vary; or could be formed with a generally planar configuration or curved about a single axis or axes extending in only one direction. In other embodiments, different shapes of the legs 44, 46 could be used instead of the shapes described above; in particular, to accommodate different lip shapes or different uses. In other embodiments, the outer wear surface 50 may not include a raised central portion 61. In other embodiments, the front surface 84 extends from between approximately 40% and 80% of the width of the adjacent lock aperture 62. In other embodiments a different shape or length of calibrated indicator 86 may be used. In other embodiments, the depth and width of the recess 86 may be selected based on the thickness of the narrowed central part 70. In other embodiments, the calibrated recess 86 may extend for between 50% and 90% of the distance from the upper leg narrow strip 65 to the front edge 72.

TABLE-US-00001 List of Reference Numerals wear assembly 10 lip 12 bucket 13 forwardly projecting noses 14 base 16 ramp portion 18 wear member (shroud) 20 lock 22 threaded lock aperture 24 front base surface 30 upper base surface 32 side base surfaces 34 upstanding boss 36 boss rear surface 38 front-facing wearable portion 40 rear-facing mounting portion 42 spaced apart legs 44, 46 cavity 48 shroud central portion 49 outer wear surface 50 (upper ground engaging surface) inner coupling surface 52 outer wear surface 54 (lower ground engaging surface) inner coupling surface 56 shroud front edge 58 lifting hook 60 raised central portion 61 lock aperture 62 upper leg rear edge 63 lifting feature 64 upper leg narrow strip 65 second (upper) lifting hook 66 lock aperture front wall 67 lock aperture opposing sidewalls 68a,b lock aperture rear wall portions 69a,b narrowed central part 70 front edge 72 lower support surface 76 lower rear edge 78 rear engaging surface 80 upper edge 82 front (upper) surface 84 calibrated wear indicator 86 lifting strap 90