Patent Description:
During excavating operations, replaceable wear members are typically used to protect earth working equipment such as excavation buckets. During use, the wear members gradually wear down due to the abrasive conditions and heavy loading. Once depleted, the wear members are removed from the equipment and replaced. Using wear members provides a cost-effective approach to digging and other earth working operations because it lessens the need of having to repair or replace the more expensive underlying equipment such as the lip or other portions of the equipment.

A set of wear members are commonly secured to earth working equipment by mechanical means (for example, a lock pin, bolt, or other locking mechanism). A set of teeth can be installed to the lip of a digging bucket to break up the ground ahead of the bucket and to protect the bucket lip from excessive wear. Where the teeth wear evenly, the entire set of teeth can be replaced simultaneously at the end of their service life. However, during earth working operations, wear members may be subjected to a variety of directional forces, which can include axial, vertical, and lateral loads and impacts, that can result in damage to or earlier wearing of an individual tooth requiring replacement of a single tooth or less than all of the teeth. <CIT> discloses a wear member with the features of the preamble of claim <NUM>.

The present invention pertains to wear members for earth working equipment that are mechanically secured to the equipment. The wear assemblies according to some embodiments of the invention are reliable, safe, easy to use, versatile, given to high productivity and/or can be individually replaced with little machine downtime.

According to the invention there is provided a wear member for earth working equipment, the wear member defining a longitudinal axis and comprising: a body defining a rearward opening cavity dimensioned to receive a base; first and second lateral portions extending from opposing sides of the body and defining a front edge for engaging earth, the first lateral portion defining a complementary formation to the second lateral formation to enable axial insertion and removal of a wear member mounted between adjacent wear members due to the open removal path defined by the complementary formations, and to resist rotational movement of the wear member about the longitudinal axis.

The wear member further comprises a lip mount including a pair of rearward extending portions disposed on opposing lateral sides of the body and being dimensioned to engage on an upper and lower surface of a lip plate on an excavating bucket to provide further resistance to rotational movement of the wear member about the longitudinal axis. The lip mount also reduces gaps between adjacent wear members, thereby reducing the potential for ingress of debris or other particles into the lateral portions.

Optionally, each of the pair of rearward extending portions comprises a pair of arms dimensioned and configured to engage with the lip plate.

Optionally, the complementary formations on the first and second lateral portions comprise offset planar surfaces.

Optionally, the planar surfaces are offset in a direction transverse to a plane extending through one of the first and second lateral portions. In some embodiments, the planar surfaces are vertically offset from each other, so that one planar surface slides immediately below the other planar surface.

Optionally, the planar surfaces have substantially the same lateral width and extend forwards of the body.

Optionally, the first and second lateral portions provide a seal to reduce or prevent ingress of earth or other material into the wear member.

Optionally, the front edge provides a continuous edge substantially free from gaps, or alternatively completely free from gaps.

Alternatively, the front edge may define a serrated edge, or an edge defining spaced gaps therealong, such as between adjacent teeth. A serrated edge may provide better earth penetration for the earth working equipment.

Optionally, the wear member further comprises a third lateral portion located beneath the second lateral portion, and defining an upper surface, the second and third lateral portions defining an insertion gap therebetween, and the first lateral portion further comprises an insertion portion defined by the complementary formation of the first lateral portion and a lower surface on an opposite side of the first lateral portion to the complementary formation. This enables the insertion portion of one wear member to be inserted into the insertion gap of an adjacent wear member.

Optionally, the third lateral portion extends for substantially the same lateral width as the second lateral portion but only extends part-way along the length of the second lateral portion.

Optionally, the third lateral portion is located closer to a rear of the wear member than to the front edge.

Optionally, the upper surface of the third lateral portion and the complementary formations of the first and second lateral portions are all planar surfaces.

Optionally, the complementary formations of the first and second lateral portions are surfaces that are spaced apart but generally aligned relative to a plane (for example, by deviating by ten degrees or less from a line parallel to the plane), or closely aligned (for example, by deviating by five degrees or less from a line parallel to the plane), or generally parallel (for example, by deviating by approximately two degrees or less from a line parallel to the plane). In one embodiment, the engaging formation of the first lateral portion (for example, an upper surface) may slope at a small angle (less than five degrees) away from the body such that the height of the first lateral portion reduces as it extends away from the body. Similarly, the engaging formation of the second lateral portion (for example, a lower surface) may slope at a similar small angle towards from the body such that the height of the second lateral portion increases as it extends towards from the body.

According to an embodiment there is provided a wear assembly for earth working equipment, the wear assembly comprising: a lip plate for mounting on an excavating bucket; first, adapters mounted on the lip plate and each defining a base protruding therefrom; and wear members as previously described.

The various features of the above-noted embodiments can be used independently of each other or collectively with all or some of the different features in securing a wear member to an edge of earth working equipment. The noted features are exemplary summary observations of certain ideas of the various concepts of the invention and are not intended to be exhaustive or essential. The foregoing and other objectives, features, and advantages of the disclosed embodiments will be more readily understood in view of the following detailed description of certain embodiments and the accompanying drawings. Understanding that the drawings depict only certain embodiments and are not, therefore, to be considered limiting in nature, these embodiments will be described and explained with additional specificity and detail.

Wear members are applied to many kinds of earth working equipment to extend the service life of the equipment. The present invention is related to wear members secured along the digging edge of an earth working equipment such as a bucket, and wear assemblies comprising such wear members. Further examples described herein not within the scope of the invention defined by the claims relate to methods for installing and removing wear members on such edges.

Referring now to the Figures, <FIG> shows a wear assembly <NUM> including wear members <NUM>, where the wear assembly <NUM> is designed to be attached to earth working equipment. In the illustrated example, the wear member <NUM> is a point or tooth. The wear assembly <NUM> includes a profiled lip <NUM> onto which the teeth <NUM> are attached. The profiled lip <NUM> comprises a lip plate <NUM> attached to an edge (not shown) of an earthmoving bucket (not shown) and adapters 8A welded to the lip plate <NUM>. Each adapter 8A defines a nose 8B (best seen in <FIG>) extending therefrom and protruding beyond the lip plate <NUM>. The adapters 8A could alternatively be secured by mechanical means such as a Whisler (trade mark) wedge and clamp, or the noses 8B could be formed as part of the lip plate <NUM>. The lip plate <NUM> can have a variety of different designs but preferably has a linear leading surface. The profiled lip <NUM> has a direction of advance during operation of the earth working equipment (e.g., a digging operation).

Tooth <NUM> of wear assembly <NUM> includes a working portion <NUM> (best seen in <FIG>) tapering to a narrowed front working edge <NUM> and a mounting portion <NUM> (best seen in <FIG>) that includes a rearward opening cavity <NUM> that receives a nose 8B extending forward of the lip plate <NUM>. The mounting portion <NUM> includes a lip mount comprising one or more rearwardly extending legs <NUM> and <NUM> on one or each side of cavity <NUM>. In this embodiment each leg <NUM>, <NUM> straddles (above and below) the lip plate <NUM> thereby providing stabilization for the tooth <NUM> and resisting rotational forces on the tooth <NUM>.

Cavity <NUM> is defined by top, bottom and side walls that form a central body <NUM> of the tooth <NUM>. The tooth body <NUM> preferably includes an opening 28A that receives a lock <NUM> to releasably secure the tooth <NUM> to the lip <NUM> (via the adapter 8A). Cavity <NUM> and opening 28A could have a shape selected from a number of different shapes to suit the kind of fit, stabilization, locking, etc. that is desired for a particular application of the tooth <NUM>. In the illustrated embodiment, the cavity <NUM>, opening 28A and lock <NUM> received into opening 28A are as disclosed in <CIT>. Each tooth <NUM> has a longitudinal axis <NUM> that is defined by a centerline extending generally in the direction of advancement of the lip <NUM> during operation of the earth working equipment.

During use, the tooth <NUM> contacts the earth or other material during the excavation process to protect the lip <NUM>, ease penetration and/or gather material in the bucket. The front edges <NUM> of the teeth <NUM> when installed on the lip <NUM> can collectively align to form a generally continuous linear edge that can be used for leveling or flattening earth or digging smooth walled and/or floored holes or other digging operations. This wider configuration of each tooth <NUM> to form a generally continuous edge can generate increased risks of the tooth <NUM> bending or turning (i.e., generally about axis <NUM>) during digging. The above-mentioned legs <NUM>, <NUM> on both sides of the lip plate <NUM> help resist such turning. Tooth <NUM> includes a first lateral portion or wing <NUM> that extends away laterally from body <NUM> and a second lateral portion or wing <NUM> that extends away laterally on the opposite side from body <NUM>. Each lateral portion <NUM>, <NUM> extends for most of the length of the tooth <NUM> from the working portion <NUM> to the mounting portion <NUM>, but in other embodiments they may have gaps or extend only partially along the length. Wings <NUM>, <NUM> overlap with the wings (<NUM>, <NUM> respectively) on adjacent teeth <NUM> to ensure a generally continuous edge without significant gaps and/or provide support against turning of the teeth about axis <NUM>. The lateral portions <NUM>, <NUM> decrease in thickness, e.g., in a step fashion, as they extend laterally from the body <NUM>. Each lateral portion <NUM>, <NUM> defines an edge 18A and 20A from which a tongue 18B, 20B extends. Opposite surfaces of the tongues 18B, 20B provide complementary formations to each other, so that tongues 18B, 20B from adjacent teeth <NUM> slidingly engage in an overlapping relationship with corresponding tongues 20B, 18B respectively of the adjacent teeth <NUM>, thereby providing a partial overlap of the lateral portions <NUM>, <NUM>.

The lateral portions <NUM>, <NUM> extend laterally to peripheries or edges that are parallel on opposite sides and perpendicular to the linear leading edge to form a generally rectangular shape but could alternatively have non-parallel and/or non-linear side edges. In this embodiment, the lateral portions <NUM>, <NUM> comprise generally planar surfaces that have a small slope, as shown in <FIG>. An upper surface of the first lateral portion <NUM> has a downward slope (two degrees) away from the body <NUM>; whereas, a lower surface of the second lateral portion <NUM> has a similar but upward slope (two degrees) away from the body <NUM>.

The lateral portions <NUM>, <NUM> can be at staggered positions (or vertically offset). One lateral portion <NUM> can extend on a plane above the longitudinal axis <NUM> and the opposite lateral portion <NUM> can extend on a plane below the longitudinal axis <NUM>. The tooth <NUM> can include an optional, additional (third) laterally extending portion or wing <NUM> extending laterally from body <NUM> below and spaced from wing <NUM>. Lower lateral portion <NUM> can be narrower than the upper lateral portion <NUM> extending forward and back only a limited distance. This construction is preferred to reduce the removal force when impacted earthen fines are present, and to reduce the distance for complete disengagement, but other arrangements are possible. Wing <NUM> can provide additional resistance to turning of the tooth about axis <NUM>; i.e., the upper and lower lateral portions <NUM> and <NUM> form an opening (an insertion gap) that accepts the lateral portion <NUM> (an insertion portion) of an adjacent tooth <NUM> to stabilize the tooth <NUM> from rotation about the nose 8B. Other or additional overlaps could be provided.

While a linear leading edge for the assembly <NUM> is illustrated, other configurations can be provided. The leading edges of the assembly <NUM> can form a continuous linear leading edge angled to the longitudinal axis <NUM>, a curved edge, a staggered edge, or linear edge portions that meet at an angle where the lateral portions overlap with adjacent wear member lateral portions.

In the illustrated embodiment, the first and second lateral portions <NUM> and <NUM> each includes a planar face 18B and 20B substantially parallel to a plane through the longitudinal axis <NUM> that bears on the corresponding planar face of the adjacent tooth <NUM>, but non-parallel surfaces are possible. Some wear members (or corner teeth) <NUM>, <NUM> are provided as corner members.

In particular, left corner tooth <NUM> includes only the first lateral portion <NUM>; and the right corner tooth <NUM> includes only the second lateral portion <NUM>.

Each corner tooth <NUM>, <NUM> can include both lateral portions, if desired. In general, each corner tooth <NUM>, <NUM> can have one of the lateral extensions included on teeth <NUM>. In the illustrated embodiment, the corner tooth <NUM> includes leg <NUM> and wing <NUM>, and corner tooth <NUM> includes leg <NUM> and wings <NUM>, <NUM>. Alternatively, teeth <NUM> could be used on the ends and form the corner teeth as well as the medial teeth. Also, alternatively, other configurations of corner tooth could be used.

In the illustrated embodiment, tongue 18B is a continuous extension of the bottom surface of the wing <NUM>, while tongue 20B is a continuous extension of the top surface of the wing <NUM>. However, different configurations may be selected, such as tongue 20B being along the bottom and tongue 18B along the top, both tongues 18B, 20B being along the top surface or both along the bottom surface (in which case the adjacent teeth would have the opposite configuration), or having a tongue and groove arrangement (e.g., wing <NUM> could have a central orientation and wing <NUM> could be formed by two spaced apart lateral extensions to receive tongue 18B of the adjacent tooth).

In the illustrated embodiment, left corner tooth <NUM> (see particularly <FIG> and <FIG>) includes a body <NUM> with rear cavity <NUM> and lock opening 28A, rearward extending legs <NUM> to straddle the lip plate <NUM>, working edge <NUM> and lateral portion <NUM> similar to lateral portion <NUM>. The corner teeth <NUM>, <NUM> of the wear assembly <NUM> typically experience increased wear as compared to the medial teeth <NUM> and the exposed square corner can become rounded. Left corner member <NUM> includes a thickened outer edge or upright arm <NUM> with an inner face 42A to form an edge wall. The edge wall can optionally curve inward and/or be inclined inward extending rearward from working edge <NUM>. The inward curve of face 42A can guide collected material inward toward the center of the bucket. Alternatively, the horizontal thickness of the outer edge can increase, diverging as it extends rearward to guide collected material toward the center of the lip <NUM> during operation. The increased thickness of the wear member outer edges (or arms) <NUM> provides additional material at a high wear area of the assembly <NUM>, increases the life of the corner wear member <NUM> and/or guides earth material into the bucket during use.

Right corner tooth <NUM> (see particularly <FIG> and <FIG>) includes a rearward opening cavity <NUM>, rearward extending legs <NUM> to straddle the lip plate <NUM>, a thickened edge or upright guide <NUM> (preferably a mirror image of edge (or arm) <NUM> on corner member <NUM>) to resist wear with an inner face 46A. Right corner member <NUM> can include an upper lateral portion <NUM> on the edge with a lower lateral portion <NUM> similar to previously described teeth <NUM>.

The working edge <NUM> engaging earthen materials generates forces on the supporting surfaces of the teeth <NUM>, <NUM>, <NUM>. The additional width of the teeth <NUM>, <NUM>, <NUM> provided by the lateral portions <NUM>, <NUM> generates strong torque forces on the teeth <NUM>, <NUM>, <NUM> during operation. Assembling the teeth <NUM>, <NUM>, <NUM> to the digging edge of the bucket, the lateral portions <NUM>, <NUM> of each tooth <NUM> overlap with lateral portions <NUM>, <NUM> respectively, of adjacent teeth <NUM>. Lateral portion <NUM> can be received in the gap between lateral portion <NUM> and <NUM> of the adjacent tooth <NUM> to provide support to the adjacent lateral portion <NUM>, <NUM>.

The rearwardly extending legs <NUM> and <NUM> bear on the lip plate <NUM>. These bearing surfaces at the side of the teeth <NUM> and the rear of the teeth <NUM> as well as the bearing surfaces in cavity <NUM> bearing on the nose 8B stabilize the teeth <NUM> and resist torque, vertical and/or axial forces generated by digging operations.

The wings <NUM>, <NUM>, <NUM> and legs <NUM>, <NUM> as well as possibly other portions of teeth <NUM>, <NUM>, <NUM> are interlocked with each other and/or the lip plate <NUM> for support in resisting the various digging forces likely to be encountered during use and/or forming the continuous edge. The teeth also preferably form open removal paths for each of the overlapping portions <NUM>, <NUM>, <NUM>, <NUM>, <NUM> to move forwardly independently of the adjacent teeth to permit individual replacement of each tooth <NUM>, <NUM>, <NUM>. Conventionally, teeth forming continuous edges have been overlapped for support in ways that require removal of adjacent teeth when replacement of a tooth is needed. Whereas in the illustrated embodiment, wing <NUM> can slide forward relative to wings <NUM>, <NUM> with which it overlaps on the adjacent tooth, and wings <NUM>, <NUM> can slide forward relative to the wing <NUM> with which it overlaps. The adjacent teeth also do not block the forward movement of legs <NUM>, <NUM> straddling lip plate <NUM>. In the illustrated embodiment, the removal path for each tooth <NUM>, <NUM>, <NUM> is along a linear path but in other embodiments, the removal path could have a non-linear path; as one example, the removal path could be curved.

With the tooth seated on the nose 8B of adapter 8A (which is received in cavity <NUM>), lock <NUM> can be inserted into opening 28A. The lock <NUM> can be a hammerless lock, if preferred, but that is not required.

These embodiments are described herein in the context of a wear assembly for one kind of bucket. It should be understood that this is merely one example of the disclosed subject matter and is not meant to be limiting. Wear members in accordance with the present invention may have other constructions for use on a wide variety of buckets including, for example, buckets for hydraulic excavators, loaders, cable shovels, face shovels, etc., or for use on other products. Relative terms such as top, bottom, forward, rearward, left and right are used herein for ease of discussion and are not intended to be limiting.

Claim 1:
A wear member (<NUM>) for earth working equipment, the wear member defining a longitudinal axis (<NUM>) along a centerline extending in the direction of advancement of the earth working equipment, the wear member comprising:
a body (<NUM>) defining a rearward opening cavity (<NUM>) dimensioned to receive a base of the earth working equipment; and
first and second lateral portions (<NUM>, <NUM>) extending from opposing sides of the body and defining a front edge (<NUM>) for engaging earth, the first lateral portion defining a first complementary formation (<NUM>) and the second lateral portion defining a second complementary formation (<NUM>),
the first and second complementary formations (<NUM>, <NUM>) complementing each other so as to engage opposing complementary formations on adjacent identical wear members to (i) enable axial insertion and removal of the wear member mounted between the adjacent wear members on the earth working equipment due to an open removal path defined by the engaged complementary formations (<NUM>, <NUM>) and (ii) resist rotational movement of the wear member about the longitudinal axis, characterized in that the wear member (<NUM>) , further comprises a lip mount (<NUM>) including a pair of rearward extending portions (<NUM>, <NUM>) disposed on opposing lateral sides of the body (<NUM>) and being dimensioned to engage on an upper and lower surfaces of a lip plate (<NUM>) on an excavating bucket to provide further resistance to rotational movement of the wear member about the longitudinal axis.