Patent Publication Number: US-9840830-B2

Title: Replaceable wear strips for ground engaging equipment

Description:
TECHNICAL FIELD 
     This relates to replaceable wear strips for attachment to the exterior surface of ground engaging equipment, such as excavating equipment, excavator buckets, etc. 
     BACKGROUND 
     During use, ground engaging equipment, such as excavating equipment, are subjected to abrasive and impact forces that can cause damage or wear to the structural material of the bucket. U.S. Pat. No. 8,336,233 teaches a wear plate assembly for attachment to the back of an excavator bucket to protect the outer surface from abrasion. 
     Referring to  FIG. 1 , a typical excavator bucket  100  is shown without any wear strips. In use, the exterior surface  102  of excavator bucket  100  comes into contact with rocks, soil, and other materials that may damage or cause wear to excavator bucket  100 . In order to extend the life of excavator bucket  100 , wear strips  104  may be added to exterior surface  102 , as shown in  FIG. 2 . These wear strips  104  are typically attached in a permanent manner that is not intended to be removed, such as by welding strip  104  to excavator bucket  100 . 
     SUMMARY 
     According to an aspect, there is provided a wear strip assembly for excavator equipment, the wear strip assembly comprising a wear strip having an engagement profile and a wear surface, and a wear strip support defining a receiving profile complementary to the engagement profile of the wear strip, such that the engagement profile of the wear strip removably engages the receiving profile of the wear strip support, the wear strip support having one or more openings distributed along an inner edge of the wear strip support and below the receiving profile, the one or more openings having a thickness that permits the wear strip support to be welded to the ground engaging equipment. 
     According to another aspect, the wear strip support may comprise first and second portions that may be spaced to define a desired width of the receiving profile. 
     According to another aspect, the one or more openings may be defined between the first and second portions. 
     According to another aspect, the wear strip support may comprise a unitary body and the openings may be formed in a bottom surface of the wear strip support. 
     According to another aspect, the wear strip may be held in relative position to the wear strip support exclusively by a weld at one or both ends of the weld strip. 
     According to an aspect, there is provided an excavator bucket having a plurality of wear strip assemblies, the excavator bucket comprising an interior and an exterior, the wear strip assemblies comprising a wear strip having an engagement profile and a wear surface, and a wear strip support defining a receiving profile complementary to the engagement profile of the wear strip, such that the engagement profile of the wear strip removably engages the receiving profile of the wear strip support, the wear strip support having one or more openings distributed along an inner edge of the wear strip support, and below the receiving profile, the one or more openings having a thickness that permits the wear strip support to be welded to the exterior of the excavator bucket. 
     According to another aspect, the wear strip support may comprise first and second portions that may be spaced to define a desired width of the receiving profile. 
     According to another aspect, the one or more openings may be defined between the first and second portions. 
     According to another aspect, the wear strip support may comprise a unitary body and the openings may be formed in a bottom surface of the wear strip support. 
     According to another aspect, the wear strip may be held in relative position to the wear strip support exclusively by a weld at one or both ends of the weld strip. 
     In other aspects, the features described above may be combined together in any reasonable combination as will be recognized by those skilled in the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to be in any way limiting, wherein: 
         FIG. 1  is a perspective view of an excavator bucket prior to installation of wear strips. 
         FIG. 2  is a perspective view of an excavator bucket showing prior art wear strips welded directly to the bucket. 
         FIG. 3  is a perspective view of an excavator bucket with wear strip assemblies installed on an outer surface. 
         FIG. 4  is a detailed side elevation view in section of an engagement profile of the wear strip assemblies shown in  FIG. 3 . 
         FIG. 5  is a detailed perspective view of an alternate engagement profile of the wear strip assemblies shown in  FIG. 3 . 
         FIG. 6  is a detailed side elevation view in section of the engagement profile shown in  FIG. 5 . 
         FIG. 7  is a detailed perspective view of a wear strip assembly that has been tack welded in place. 
         FIG. 8  is a detailed perspective view of a wear strip assembly with an engagement profile that has an adjustable width. 
     
    
    
     DETAILED DESCRIPTION 
     A wear strip assembly, generally identified by reference numeral  10 , will now be described with reference to  FIG. 1 through 8 . While the embodiments described herein relate to excavator buckets, it will be understood that wear strip assembly  10  may be used on any ground engaging equipment, such as equipment used in excavating or earth-moving operations, and may be attached to any suitable part of the equipment that it may be desired to protect from wear. This includes static components as well as moving components, as well as those components that are actively engaging the material being excavated and those that provide support or control but do not directly engage the material being excavated. 
     Referring to  FIG. 5 , wear strip assembly  10  has a wear strip  12  having an engagement profile  14  and a wear surface  16 . Engagement profile  14  may take a variety of forms, such as a rounded tab profile shown in  FIG. 4 , or an angular profile as shown in  FIG. 6 . Wear strip assembly  10  also has a wear strip support  18  defining a receiving profile  20  that is complementary to engagement profile  14  of wear strip  12 , as shown in  FIG. 4  and  FIG. 6 . Referring to  FIG. 5 , engagement profile  14  removably engages receiving profile  20 , such that wear strip  12  can be removably attached to wear strip support  18 . As shown in  FIG. 5 , the complementary profiles allow wear strip  12  to slide into wear strip support  18 , and the shape of the profiles prevents wear strip  12  from being removed perpendicular to the surface. Preferably, weld strip  12  and wear strip support  18  are single, extruded bodies along their length as this increases the strength and simplifies installation. It will be understood that it may be possible to provide various lengths of weld strips  12  and wear strip supports  18 , such that there would be more than one piece installed on the exterior surface of the ground engaging equipment. However, longer pieces are preferred, such as no more than 1 or 2 pieces for a length of weld strip  12  and wear strip support  18 . In addition, as wear strip  12  slides into receiving profile  20 , it will also be understood that wear strip assembly  10  is ideally used on flat sections of surfaces, or along a flat line on a surface, such as transversely on an excavator bucket as shown in the drawings. It may be possible to install wear strip supports  18  on a curved surface, however the curve must have a constant radius of curvature, and there must be sufficient access on either side of wear strip support  18  to allow a curved wear strip  12  to be inserted or removed. 
     Wear strip support  18  has one or more openings  22  distributed along an inner edge of wear strip support  18  and below receiving profile  20 . As shown in  FIG. 8 , wear strip support  18  may be made from first portion  24  and second portion  26  that can be spaced to define a desired width of receiving profile  20 . In the case of wear strip support  18  having two portions  24  and  26 , the one or more openings  22  are defined between first and second portions  24  and  26 , as shown. Alternatively, as shown in  FIG. 5 , wear strip support  18  may be a unitary body and in this case openings  22  are formed in a bottom surface  28  of wear strip support  18 . The one or more openings  22  have a thickness that permits wear strip support  18  to be welded to excavator bucket  100  without the weld material interfering with the movement of wear strips  12  through wear strip support  18 . In order to prevent lateral movement of wear strip  12  relative to wear strip support  18 , wear strip  12  may be held in relative position to wear strip support  18  by a weld  30  at one or both ends of wear strip  12 . Weld strip  12  may be welded at both ends or only at one end, depending on the preferences of the user. If weld strip  12  is not a single piece as shown in the depicted embodiments and as is be preferred, it will be necessary to apply welds at either end. The weld may be for example, a tack weld that may easily be removed. It will be understood that weld  30  is not intended to be strong enough to fully install wear strip  12 ; rather it is merely intended to be used to hold wear strip  12  against lateral movement out from wear strip support  18 , while allowing wear strip  12  to be easily removed. Other approaches to holding wear strip  12  will be apparent to those skilled in the art. 
     The width of wear strip support  18  is preferably narrow enough to allow them to be installed on a curved surface of excavator bucket  100  without difficulty. This will depend on the curvature of bucket  100  and the tolerances implemented during construction. 
     Referring to  FIG. 3 , excavator bucket  100  is shown with removable wear strip assemblies  10  being installed by first attaching wear strip supports  18  to excavator bucket  100 . Referring to  FIG. 5 , when wear strip support  18  is a unitary body, wear strip support  18  is welded around its perimeter, as well as in openings  22 , to properly anchor wear strip supports  18  to excavator bucket  100 . Referring to  FIG. 8 , wear strip support  18  may also be funned from two portions  24  and  26 , such that wear strip support  18  is installed by welding around the perimeter of each portion  24  and  28 , including in openings  22 . Wear strip support may be made from two portions  24  and  26 , such as to accommodate a variety of possible widths of wear strips  12  without having to provide multiple sizes of wear strip supports  18 . If using two portions  21  and  26 , portion  24  may be installed first, and the width of wear strip  12  may be used to set the position of second portion  26 . Both wear strips  12  and wear strip supports  18  may be extruded, molded or formed using other known techniques. 
     Referring again to  FIG. 3 , once wear strip supports  18  have been installed on excavator bucket  100 , wear strips  12  are slid into wear strip supports  18  using engagement profile  14  and receiving profile  20 . Referring to  FIG. 7 , wear strips  12  may then be secured against lateral movement of wear strip  12  relative to wear strip support  18 , such as by applying a weld  30 . Weld  30  is preferably applied sparingly such that it is easy to remove when desired to do so. When wear strip  12  becomes damaged or worn, it is released to allow lateral movement, such as by removing weld  30 , and wear strip  12  is then slid out of wear strip support  18 . A new wear strip  12  can then be slid into place and re-welded. 
     By providing removable and replaceable wear strips, it becomes possible to continually replace wear strips and protect bucket  100  against unnecessary wear. If wear strips  12  were installed directly on excavator bucket  100  as is commonly done, it becomes difficult to remove and replace wear strips  12  without damaging excavator bucket  100 . In addition, wear strips  12  may be made from a different material with beneficial properties for wear strips that may otherwise be difficult to secure by welding or otherwise install on bucket  100 . 
     In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the elements is present, unless the context clearly requires that there be one and only one of the elements. 
     The scope of the following claims should not be limited by the preferred embodiments set forth in the examples above and in the drawings, but should be given the broadest interpretation consistent with the description as a whole.