US20160153178A1

US20160153178A1 - Ground engaging tool with replaceable wear resistant cover

Info

Publication number: US20160153178A1
Application number: US15/015,152
Authority: US
Inventors: Aaron K. Amstutz
Original assignee: Caterpillar Inc
Current assignee: Caterpillar Inc
Priority date: 2016-02-04
Filing date: 2016-02-04
Publication date: 2016-06-02

Abstract

A ground engaging tool (GET) assembly is provided. The ground engaging tool assembly includes at least one tooth, and at least one cover assembly. The at least one cover assembly is adapted to completely cover and attach to the at least one tooth. The at least one cover assembly including an outer member having a plurality of insert holders configured to hold a plurality of inserts. The plurality of inserts being coated with a wear resistant material, and having a predefined shape. A liner member being coupled to an inner surface of the outer member. The plurality of inserts is coupled to the outer member, and the predefined shape of the plurality of inserts being adapted to cover an entire surface of the outer member.

Description

TECHNICAL FIELD

The present disclosure relates to a ground engaging tool assembly, and more specifically, to the ground engaging tool assembly having a protective cover with replaceable wear resistant inserts.

BACKGROUND

Heavy machines, such as excavators, loaders, dozers etc. employ various kinds of ground engaging tools. The ground engaging tools are utilized to perform various operations of the heavy machines, such as digging, mining etc. During the operations, the ground engaging tools get damaged due to frequent wear and tear of surfaces with earth, rocks etc.
In order to minimize wear and tear of surfaces, various techniques such as hardfacing coating and engineered coatings are employed which enhance the life of the ground engaging tools. However, such techniques fail to efficiently protect the ground engaging tools due to large size. For example, hardfacing coating on an entire tooth results in insufficient protection of teeth, and thus makes the teeth vulnerable to abrasion during the operations of the heavy machines. Also, at times, if the hardfacing coating gets damaged, then the entire coating needs to be replaced that increases the cost and is labor intensive. Therefore, there is a need for a technique which is cost effective, and easily replaceable.
U.S. Pat. No. 4,461,513 discloses a rotary stone-cutting head. The rotary stone-cutting head has a body which carries four part-spiral rows of identical cutting-tooth holders carrying respective cutter teeth. Each tooth has a flat face, and a regular array of cylindrical holes is bored in a tooth after it is hardened. The array of cylindrical holes receives stems or shanks of hardened-metal breaking elements having heads formed with points directed perpendicular to the flat face. The upper surfaces of the elements are shown to be conical to form the points, they can be pyramidal, with flat generally triangular facets. The reference further discloses that when the elements are badly worn, they are simply punched out from the back and new ones can easily be mounted on the teeth. However, this technique fails to coat an entire surface of the teeth. Therefore, there is a need for inserts employed within the ground engaging tools, which are cost effective, and easily replaceable.

SUMMARY OF THE DISCLOSURE

In one aspect of the present disclosure, a ground engaging tool (GET) assembly is provided. The ground engaging tool (GET) assembly includes at least one tooth. At least one cover assembly is adapted to completely cover and attach to the at least one tooth. The at least one cover assembly including an outer member having a plurality of insert holders configured to hold a plurality of inserts. The plurality of inserts being coated with a wear resistant material, and having a predefined shape. A liner member being coupled to an inner surface of the outer member. The plurality of inserts is coupled to the outer member, and the predefined shape of the plurality of inserts being adapted to cover an entire surface of the outer member.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an excavator bucket having a number of teeth, each one of the teeth covered with a cover assembly and inserts, in accordance with the concepts of the present disclosure;

FIG. 2 is a perspective view, a top view, and a side view, of a single tooth and the cover assembly with the inserts, in accordance with the concepts of the present disclosure;

FIG. 3 is a perspective view of the cover assembly without the inserts, in accordance with the concepts of the present disclosure;

FIG. 4 is a cross sectional view of the cover assembly without the inserts, in accordance with the concepts of the present disclosure;

FIG. 5 is a cross sectional view of a ground engaging tool (GET) assembly showing the single tooth and the cover assembly with the inserts, in accordance with the concepts of the present disclosure; and

FIG. 6 is a perspective view, a bottom view, and a cross sectional view of an insert showing a snap-fit design, in accordance with the concepts of the present disclosure.

DETAILED DESCRIPTION

Referring to FIG. 1, an excavator bucket 10 having a ground engaging tool (GET) assembly 12, a number of tooth assemblies 14, a top assembly 16, a curved heel section 18, a first side 20, a second side 22, hinge plates 24, bores 26, and a base edge 28. The ground engaging tool assembly 12 includes the number of tooth assemblies 14. The number of tooth assemblies 14 includes at least one tooth 30 and at least one cover assembly 32 with a number of inserts 34. The top assembly 16 includes the hinge plates 24 having the bores 26. The detailed description of the ground engaging tool assembly 12 is described later in conjunction with FIG. 2. The excavator bucket 10 further includes various other components such as, but not limited to, a side plate, a side bar etc. For the purpose of simplicity, the various other components of the excavator bucket 10 are not labeled in FIG. 1.
The curved heel section 18 is attached with the top assembly 16, the first side 20, and the second side 22, to form the excavator bucket 10. The top assembly 16 is also referred as a hinge assembly. Further, the top assembly 16 includes the hinge plates 24 having the bores 26. The bores 26 are axially aligned, and support a stick pin (not shown) that passes through a stick (not shown) of an excavator (not shown). Further, the base edge 28 is adapted to mount several adapters, tips, and base edge protectors, which are referred as ground engaging tools. The ground engaging tools are utilized for various operations, such as digging, mining etc. It will be apparent to one skilled in the art that the various operations mentioned above have been provided only for illustration purposes.
Referring to FIGS. 2, 3, and 4, the cover assembly 32 is attached to the tooth 30 (shown in FIG. 1) in such a manner that the cover assembly 32 completely covers the tooth 30. The cover assembly 32 includes an outer member 38 and a liner member 56 (shown in FIG. 4). The outer member 38 and the liner member 56 are permanently attached to each other. The outer member 38 having an outer surface 58 and an inner surface 60. Similarly, the liner member 56 has an outer surface 62 and an inner surface 64. The outer surface 62 of the liner member 56 is attached to the inner surface 60 of the outer member 38. The inner surface 64 of the liner member 56 is inserted onto the tooth 30 of the ground engaging tool (GET) assembly 12 which may have an interference fit. The outer member 38 of the cover assembly 32 is made of materials such as, but not limited to, steel, or any hard material, etc. The liner member 56 of the cover assembly 32 is made of a resilient material, such as a rubber material. It should be noted that the materials mentioned above for the outer member 38 and the liner member 56 have been provided only for illustration purposes. The outer member 38 and the liner member 56 may be made of some other material as well, without departing from the scope of the disclosure.
Further, the outer member 38 of the cover assembly 32 is provided with a number of insert holders 40. The insert holders 40 have an annular opening extending from the outer surface 58 to the inner surface 60 of the outer member 38. The insert holders 40 include a first cylindrical portion 66 and a second cylindrical portion 68. The first cylindrical portion 66 is smaller than the second cylindrical portion 68, and both the first cylindrical portion 66 and the second cylindrical portion 68 are coaxially aligned with each other. The first cylindrical portion 66 is connected to the second cylindrical portion 68 forming a shoulder portion 70 to accommodate seating of the inserts 34. Further, the insert holders 40 are adapted to hold the inserts 34 of the predefined shape. The inserts 34 are coupled to the outer member 38 of the cover assembly 32 by means of a snap-fit design 51, such that the predefined shape of the inserts 34 are adapted to cover an entire surface of the outer member 38. The predefined shape of the inserts 34 is an isosceles triangle. It will be apparent to one skilled in the art that the predefined shape of the inserts 34 mentioned above has been provided only for illustration purposes. The predefined shape of the inserts 34 may be a trapezoidal shape or any other shape that can completely cover the entire surface of the outer member 38, without departing from the scope of the disclosure. It should be noted that an isosceles triangle covers the entire outside geometry of the outer member 38 with singular insert 34 geometry. This makes subsequent insert 34 replacements particularly easy since there are not multiple variations on insert 34 size which may cause confusion.
Referring to FIGS. 2, 3, 4, 5, and 6, the inserts 34 having a top portion 44 and a bottom portion 46. Further, the inserts 34 having a first member 48, two or more legs 50, and a shoulder member 52. The first member 48 is connected to the two or more legs 50 forming the shoulder member 52 (shown in FIG. 5). Further, the ground engaging tool assembly 12 includes a single insert 36 which is attached to a nose 42 of the outer member 38. It should be noted that a size and shape of the single insert 36 may be different from the size and shape of the inserts 34 mentioned above.
Referring to FIGS. 2, 3, 4, 5, and 6, the inserts 34 are coupled to the outer member 38 through the snap-fit design 51 (shown in FIG. 6). The snap-fit design 51 (shown in FIG. 6) includes the two or more legs 50 (i.e., four are shown in FIG. 6) that may displaceably pass through the first cylindrical portion 66, expand within the second cylindrical portion 68, and anchor on the shoulder portion 70. Each leg 50 having an inner surface which is threaded so that the snap-fit design 51 may receive a set screw for insert 34 retention. Further, lines 54 (shown in FIG. 3) provided on the outer surface 58 of the outer member 38 forms a triangular region that facilitates to hold and orient the inserts 34 correctly. Alternatively, the inserts 34 are coupled to the outer member 38 through various retention mechanisms known in the art. Further, each insert 34 has the snap-fit design 51 that is held in place with a set screw. For example, if an insert 34 gets damaged during the operation, then the insert 34 is easily replaced with another insert 34 (i.e., a new insert 34) using a removal tool (not shown). Alternatively, the inserts 34 are fastened to the outer member 38 using a number of fasteners. The fasteners such as, but not limited to, a retention set screw, a twist and lock plug, etc. Further, the inserts 34 have similar shape and size, and are coated with a wear resistant material (i.e., a hard material). The wear resistant material may include materials such as, but not limited to, polycrystalline diamond, cubic boron nitride, chromium nitride, tungsten nitride, tungsten carbide, amorphous diamond like carbon, boron aluminum magnesium alloy, titanium boride, titanium nitride, and other similar hard coatings. It should be noted that the wear resistant materials mentioned above have been provided only for illustration purposes.
The cover assembly 32 requires a mechanical attachment mechanism to the tooth 30. The cover assembly 32 may include a region (not shown) that is substantially free of inserts 34 that is configured for a mechanical attachment to the tooth 30, The means of the mechanical attachment may include pins, rotating members that capture the tooth 30 features, or other means known in the art.

INDUSTRIAL APPLICABILITY

The present disclosure provides the ground engaging tool (GET) assembly 12, The ground engaging tool (GET) assembly 12 discloses the cover assembly 32 which is attached to the tooth 30, and completely covers the tooth 30. The cover assembly 32 includes the outer member 38 having the insert holders 40 which are adapted to hold the inserts 34. The inserts 34 are coated with the wear resistant material, and having the predefined shape. The predefined shape of the inserts 34 is adapted to cover the entire surface of the outer member 38. Such type of the ground engaging tool (GET) assembly 12 protects the tooth 30 during operations of heavy machines. Further, each insert 34 has the snap-fit design 51 that is held in place with the set screw, and thus provides sufficient strength to the ground engaging tool (GET) assembly 12. Further, the cover assembly 32 having the liner member 56 which is attached to the inner surface 60 of the outer member 38 in order to keep dirt from packing in behind the cover assembly 32. Also, at times, if an insert 34 gets damaged during operations, then the insert 34 is easily replaced with another insert 34 (i.e., a new insert 34) without replacing entire coating of the tooth 30. Thus, such type of the inserts 34 is cost effective, and easily replaceable.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.

Claims

What is claimed is:

1. A ground engaging tool (GET) assembly comprising:

at least one tooth;

at least one cover assembly adapted to completely cover and attach to the at least one tooth, the at least one cover assembly including:

an outer member having a plurality of insert holders adapted to hold a plurality of inserts, the plurality of inserts being coated with a wear resistant material, and having a predefined shape; and

a liner member being coupled to an inner surface of the outer member;

wherein the plurality of inserts is coupled to the outer member, and the predefined shape of the plurality of inserts being adapted to cover an entire surface of the outer member.