Abstract:
A wear part including an attachment box with a forwardly extending ground engaging blade member having an upper surface and an extension rib extending upwardly from one lateral side of the upper surface of the blade member and extending substantially parallel to the direction of ground engagement.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to wear parts for earthmoving equipment and particularly for an improved tooth for use with earthmoving equipment. 
       BACKGROUND ART 
       [0002]    Wear parts and particularly attachable teeth for earthmoving equipment are available. 
         [0003]    One such example of an attachable tooth used for earthmoving equipment is illustrated in  FIGS. 1 and 2 . This attachable tooth  10  has an attachment box  11  or section at the rear of the tooth  10  with a circular openings  12  in the sidewalls  13  of the box  11  extending laterally therethrough to receive a pin  14  or similar in order to attach the tooth  10  to a mounting portion  15  on the earthmoving equipment. 
         [0004]    The attachment box  11  of the prior art tooth  10  is reinforced for added strength, particularly around the openings  12  in the sidewalls  13  of the box section. 
         [0005]    The attachable tooth  10  also has a forwardly extending blade portion  16 . The blade portion  16  has a centrally aligned rib  17  with the rippled surfaces  19  in between the rib  17  and the sidewalls  18  of the blade portion  16 . The rippled surfaces  19  are apparently to optimise penetration and material flow over the tooth  10 . This is ostensibly to improve the self sharpening effect of the tooth as the tooth is worn. 
         [0006]    Although not visible in the Figures, the underside of the blade portion of the tooth of the prior art has a pocket or depression which the inventors of the prior art tooth contend maintains tip sharpness without compromising point integrity. 
         [0007]    The tooth is attached to a mounting portion  15  located on the earthmoving equipment as illustrated in  FIG. 3 . 
         [0008]    It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention is directed to a wear part, which may at least partially overcome at least one of the abovementioned disadvantages or provide the consumer with a useful or commercial choice. 
         [0010]    With the foregoing in view, the present invention in one form, resides broadly in a wear part including an attachment box with a forwardly extending ground engaging blade member having an upper surface and an extension rib extending upwardly from one lateral side of the upper surface of the blade member and extending substantially parallel to the direction of ground engagement. 
         [0011]    In a further form, the present invention resides in a wear part including an attachment box with a forwardly extending ground engaging blade member having an upper surface substantially coplanar with the upper surface of the attachment box and a lower surface substantially parallel to the upper surface. 
         [0012]    The wear part of the present invention is directed towards providing a more angular tooth than the teeth used conventionally. The more angular nature of the tooth of the present invention provides advantages in the “angle of attack” of the tooth in use and also provides a tooth which, as it wears due to use, maintained its overall shape and particularly tip sharpness. The tooth of the present invention is also self sharpening as it undergoes wear. 
         [0013]    The wear part of the present invention will typically be configured as an attachable tooth common typically used in association with earthmoving equipment such as an earthmoving bucket or loader but preferably as a tooth for an earthmoving grader. 
         [0014]    As intimated above, teeth used in this manner are subject to wear and as a tooth does wear, the shape of the tooth normally changes. It is an advantage therefore for a tooth which does wear to maintain as much as possible the overall shape and in particular the sharpened tip. 
         [0015]    The wear part of the present invention includes an attachment box. In use, the attachment box is used to attach to the wear part relative to the earthmoving equipment, and typically an attachment mount is provided specifically adapted for this purpose. The attachment mounts of earthmoving equipment are typically provided in standard sizes and configurations in order that replacement wear parts can be provided and can be quickly and simply exchanged for worn or unusable parts. 
         [0016]    The attachment box of the wear part of the present invention typically has an upper wall, and opposed lower wall and a pair of the sidewalls, these walls together defining an opening into which the attachment mount will be received in use. 
         [0017]    Preferably, the upper and lower walls of the attachment box taper towards each other as they extend towards the blade portion of the wear part. The sidewalls of the attachment box are typically parallel to one another. As outlined above, the attachment box is typically adapted to receive a “standard” sized mounting portion therein and a substantially rectangular opening is provided via the rear most edges of the walls. 
         [0018]    An opening is preferably provided in each of the sidewalls of the attachment box of the present invention. The respective openings are normally provided about central axis. These openings are typically adapted to receive a pin or other fastener therethrough in order to attach the wear part to the mounting portion. 
         [0019]    It is preferred that the upper and/or lower walls of the attachment box of the present invention arcuate or curved. It is particularly preferred that both of the upper and lower walls are convex. 
         [0020]    The wear part of the present invention also has a forwardly extending, ground engaging blade member. In a preferred form, the blade member is generally rectangular in shape and has an upper surface, a lower surface, a pair of sidewalls, and a forward or leading surface. The blade member will typically be fondled integrally with the attachment box and therefore, will not have a rear wall or surface. 
         [0021]    According to a preferred embodiment, with the blade member of the wear part is typically wider than the sidewalls of the attachment box. Due to this extra width, a pair of lateral shoulder portions will normally be formed between the attachment box and the blade member. 
         [0022]    According to a particularly preferred embodiment, the forward or leading surface of the blade member is angled to provide a “sharpened” forward edge. Normally, the forward surface is angled rearwardly from the upper surface to the lower surface. In use, the sharpened forward edge will typically be approximately parallel to the ground surface when attached to the mounting portion. 
         [0023]    The forward or leading edge of the blade member is also angled rearwardly from one sidewall to the opposite side in order to form a leading tip or point. Normally the leading tip or point will be located at the intersection of the upper surface, a sidewall and the angled forward or leading surface of the blade member. The leading edge of the blade member is therefore angled rearwardly from one side to the other with respect to the attachment box. 
         [0024]    Put another way, the forward surface of the blade member of the present invention is angled rearwardly and downwardly and also is not perpendicular to the sidewalls of the blade member but instead is angled rearwardly from one sidewall to another. 
         [0025]    Further, the lower surface of the blade member will preferably be substantially parallel to the upper surface of the blade member. The blade member will preferably be solid and manufactured from a metal. 
         [0026]    According to a particularly preferred embodiment, a uniform thickness blade member extending from a forward portion of the attachment box and integrally formed therewith is provided, the blade member having an upper surface coplanar with the upper surface of the attachment box and the lower surface of the blade member parallel to the upper surface of the blade member rather than coplanar with the lower wall of the attachment box. 
         [0027]    This is in direct contrast with the prior art blade member, one form of which is illustrated in  FIGS. 1 and 2  in which the blade member is solid and tapers from the front of the attachment box to the tip, with the lower wall of the blade member coplanar with the lower wall of the attachment box and the upper wall of the blade member coplanar with the upper wall of the attachment box. Further, the prior art blade member has a “square” tip. 
         [0028]    The wear part of the present invention also has an extension rib, preferably standing proud of the upper surface of the blade member. The extension rib will typically extend upwardly from a location between one side of the blade member and the midline of the blade member. According to a preferred embodiment, the extension rib will typically extend substantially (although not exactly) parallel to a sidewall of the blade member. 
         [0029]    The extension rib is typically integrally formed with the blade member with a base portion of the extension rib spaced from the side wall of the blade member. 
         [0030]    The extension rib may preferably be angled such that the upper surface of the extension rib is offset from the base portion laterally resulting in a portion of the extension rib overhanging the sidewall of the blade member. The extension rib will typically extend rearwardly from adjacent the forward edge of the blade member and a rear wall of the extension rib will normally be located above the upper wall of the attachment box. 
         [0031]    According to alternative preferred embodiment of the present invention, there may be one of two embodiments of extension rib provided. 
         [0032]    The first preferred embodiment is an extension rib which is preferably adapted for use in situations where the wear part is used for dirt and other normal earthmoving. The extension rib of this embodiment has an upper surface which is preferably angled with respect to the upper surface of the blade, namely the extension rib increases in thickness/height as it extends from the tip of the blade member towards the root of the blade member. 
         [0033]    Accordingly, when viewed from the side, the extension rib of this embodiment is typically wedge-shaped. The extension rib of this embodiment will preferably be provided with one or more faceted rear walls, typically more than one with the surfaces of the rear walls extending in different directions, at different angles. 
         [0034]    Preferably, the upper surface of the extension rib of this embodiment is angled downwardly towards the upper surface of the blade member at the tip end of the rib, that angle becoming less prominent towards the rear of the extension rib, and more parallel to the upper surface of the blade member. 
         [0035]    The rear of the extension rib is preferably spaced further inwardly toward the midline of the blade than the tip of the extension rib. That is, the extension rib extends rearwardly at an angle across the blade. Typically, the angle is acute. 
         [0036]    Typically, the extension rib of this embodiment is of substantially uniform thickness. 
         [0037]    The second preferred embodiment is an extension rib which is preferably adapted for use in situations where the wear part is used for earthmoving in situations where it is likely that the wear part will strike trees and other above ground clearable rubble. 
         [0038]    According to this embodiment, the extension rib has a forward surface, a rear surface, an outer and an inner surface and a top surface with the base of the extension rib formed integrally with the blade member. 
         [0039]    The upper surface of the extension rib of this embodiment is preferably substantially parallel to the upper surface of the blade member. Preferably, the upper surface of the extension rib is twisted such that the root end of the upper surface is angled downwardly towards the upper surface of the blade to a larger degree than the upper surface at the tip end. 
         [0040]    The extension rib on this embodiment is preferably block shaped (rectangular) when viewed from the side. Normally, the rear surface will be angled rearwardly from the upper surface to the attachment box. Further, the extension rib of this embodiment is typically of uniform thickness over its length. 
         [0041]    Normally, the tip end of the extension rib of this embodiment is sharpened. The forward end, that is the edge at the intersection of the forward surface and the upper surface of the extension rib preferably extends forwardly of the forward edge of the blade member. 
         [0042]    Preferably, the outer forward edge of the extension rib extends downwardly and rearwardly to the blade member. It is also preferred that the inner forward edge is located behind the outer forward edge or closer to the blade member. Further, the upper forward edge is preferably located in front of the lower forward edge. 
         [0043]    The result of the above edge configurations is that the extension rib of this embodiment forms a forward point and a sharpened, forward, outer edge on the extension rib. Typically, the rear surface of the extension rib of this embodiment is substantially parallel to the forward surface. 
         [0044]    Typically, a plurality of wear parts will be mounted relative to a piece of earthmoving equipment such as a bucket or grader or the like and all will typically be of a similar configuration. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0045]    Various embodiments of the invention will be described with reference to the following drawings, in which: 
           [0046]      FIG. 1  is a perspective view from the front of a conventional wear part. 
           [0047]      FIG. 2  is a perspective view from the rear of a conventional wear part. 
           [0048]      FIG. 3  is a perspective view of a conventional tooth and the attachment arrangement to attach the tooth to equipment. 
           [0049]      FIG. 4  is a perspective view from the front of an attachment tooth according to a first embodiment configured for hard ground or dirt. 
           [0050]      FIG. 5  is a perspective view from the front of an attachment tooth according to a second embodiment configured for ground and tree clearing. 
           [0051]      FIG. 6  is a view from below of the attachment tooth illustrated in  FIG. 4 . 
           [0052]      FIG. 7  is a view from the tip of the attachment tooth illustrated in  FIG. 4 . 
           [0053]      FIG. 8  is a view from above of the attachment tooth illustrated in  FIG. 4 . 
           [0054]      FIG. 9  is a view from below of the attachment tooth illustrated in  FIG. 5 . 
           [0055]      FIG. 10  is a view from the tip of the attachment tooth illustrated in  FIG. 5 . 
           [0056]      FIG. 11  is a view from above of the attachment tooth illustrated in 
           [0057]      FIG. 5 . 
           [0058]      FIG. 12  is a view from one side of the attachment tooth illustrated in  FIG. 4 . 
           [0059]      FIG. 13  is a view from the attachment box end of the attachment tooth illustrated in  FIG. 4 . 
           [0060]      FIG. 14  is a view from the reverse side of the attachment tooth illustrated in  FIG. 4 . 
           [0061]      FIG. 15  is a view from one side of the attachment tooth illustrated in 
           [0062]      FIG. 5 . 
           [0063]      FIG. 16  is a view from the attachment box end of the attachment tooth illustrated in  FIG. 5 . 
           [0064]      FIG. 17  is a view from the reverse side of the attachment tooth illustrated in  FIG. 5 . 
           [0065]      FIG. 18  is a perspective view of the attachment tooth illustrated in  FIG. 4  in the worn condition. 
           [0066]      FIG. 19  is a view from the tip of the attachment tooth illustrated in  FIG. 18 . 
           [0067]      FIG. 20  is a view from one side of the attachment tooth illustrated in  FIG. 18 . 
           [0068]      FIG. 21  is a view from the reverse side of the attachment tooth illustrated in  FIG. 18 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0069]    According to a particularly preferred embodiment, a grader tooth  10  is provided. 
         [0070]    The grader tooth  20  of both illustrated embodiments includes an attachment box  21  and a forwardly extending blade member  22 . 
         [0071]    In use, the attachment box  21  is used to attach to the tooth  20  relative to the earthmoving equipment, and typically an attachment mount is provided specifically adapted for this purpose as is generally illustrated in  FIG. 3 . 
         [0072]    The attachment box  21  of each of the illustrated embodiments has an upper wall  23 , and opposed lower wall  24  and a pair of the sidewalls  25 , these walls together defining an opening  26  into which the attachment mount (not shown) is received in use. 
         [0073]    The upper  23  and lower  24  walls of the attachment box  21  are arcuate and taper towards each other as they extend towards the blade portion  22  of the tooth. The sidewalls  25  of the attachment box  21  are parallel to one another. As outlined above, the attachment box  21  is adapted to receive a mounting portion therein and a substantially rectangular opening  26  is provided via the rear most edges of the walls. 
         [0074]    An opening  27  is provided in each of the sidewalls of the attachment box  21  adapted to receive a pin or other fastener therethrough in order to attach the tooth to the mounting portion. 
         [0075]    The blade member  22  is generally rectangular in shape and has an upper surface  30 , a lower surface  31 , a pair of sidewalls  32 , and a forward or leading surface  33 . The blade member  22  is formed integrally with the attachment box  21  and therefore, does not have a rear wall or surface, instead having a blade root. 
         [0076]    According to the embodiments illustrated, the blade member  22  of the tooth is wider than the sidewalls of the attachment box  21 . Due to this extra width, a pair of lateral shoulder portions  28  are formed between the attachment box  21  and the blade member  22 . 
         [0077]    The forward or leading surface  33  of the blade member  22  is angled to provide a “sharpened” forward edge  29 . The forward surface  33  of the blade member  22  is angled rearwardly from the upper surface  30  to the lower  31  surface. In use, the sharpened forward edge  29  is approximately parallel to the ground surface when attached to the mounting portion. 
         [0078]    As illustrated in  FIGS. 6 and 9 , the forward edge  29  of the blade member  22  is also angled rearwardly from one sidewall  32  to the opposite side in order to form a leading point  34 . Normally, the leading point  34  is located at the intersection of the upper surface  30 , a sidewall  32  and the angled forward surface  33  of the blade member  22 . 
         [0079]    Put another way, the forward surface  33  of the blade member  22  is angled rearwardly and downwardly and also is not perpendicular to the sidewalls  32  of the blade member  22  but instead is angled rearwardly from one sidewall to another. 
         [0080]    Further, the lower surface  31  of the blade member  22  is substantially parallel to the upper surface  30  of the blade member  22 . 
         [0081]    As illustrated, the tooth  20  of the preferred embodiments also have an extension rib  35 , standing proud of the upper surface  30  of the blade member  22 . The extension rib  35  extends upwardly from a location between one side of the blade member and the midline of the blade member  22 . 
         [0082]    The extension rib  35  is integrally formed with the blade member  22  with a base portion of the extension rib  35  spaced from the sidewall  32  of the blade member  22 . The extension rib has an upper surface  36 , a forward surface  37 , at least one rear surface  38  and a pair of side surfaces  39 . 
         [0083]    The extension rib  35  is angled such that the upper surface  36  of the extension rib  35  is offset from the base portion laterally resulting in a portion of the extension rib  35  overhanging the sidewall  32  of the blade member  22 . The extension rib  35  extends rearwardly from adjacent the forward edge  29  of the blade member  22  and a rear wall  38  of the extension rib  35  is located above the upper wall  23  of the attachment box  21 . 
         [0084]    According to alternative preferred embodiment of the present invention, there may be one of two embodiments of extension rib provided which results in the two alternative embodiments of the tooth which are illustrated in  FIGS. 4 and 5 . 
         [0085]    The first preferred embodiment of the tooth  10  illustrated in  FIGS. 4 ,  6  to  8  and  12  to  14  is adapted for use in situations where the tooth is used for dirt and other normal earthmoving and has an extension rib of the first embodiment. The extension rib  35  of this embodiment has an upper surface  36  which is angled with respect to the upper surface  30  of the blade  22 , namely the extension rib  35  increases in thickness/height as it extends from the tip of the blade member  22  rearwardly towards the root of the blade member  22 . 
         [0086]    Accordingly, when viewed from the side (as in  FIGS. 12 and 14 ), the extension rib  35  of this embodiment is wedge-shaped. This extension rib  35  is provided with a pair of faceted rear walls  38 , extending in different directions, at different angles. 
         [0087]    The upper surface  36  of the extension rib  35  of this embodiment is angled downwardly towards the upper surface  30  of the blade member  22  at the tip end of the rib  35 , that angle becoming less prominent towards the rear of the extension rib  35 , and more parallel to the upper surface  30  of the blade member, as illustrated in  FIG. 12 . 
         [0088]    The rear of the extension rib  35  is spaced further inwardly toward the midline of the blade  22  than the tip of the extension rib  35  as illustrated in  FIG. 8 . That is, the extension rib  35  extends rearwardly at an angle across the blade. 
         [0089]    The extension rib  35  of this embodiment is of substantially uniform thickness. 
         [0090]    The second preferred embodiment of the tooth  10  illustrated in  FIGS. 5 ,  9  to  11  and  15  to  17  is adapted for use in situations where the tooth is used earthmoving in situations where it is likely that the tooth will strike trees and other above ground clearable rubble and has an extension rib of a second embodiment. According to this embodiment, the extension rib  35  has a forward surface  37 , a rear surface  38 , an outer  40  and an inner  41  surface and an upper  36  surface with the base of the extension rib  35  formed integrally with the blade member  22 . 
         [0091]    As illustrated in  FIGS. 15 and 17  particularly, the upper surface  36  of the extension rib  35  of this embodiment is substantially parallel to the upper surface  30  of the blade member  22 . Preferably, the upper surface  36  of the extension rib  35  is twisted such that the rear end of the upper surface  36  is angled downwardly towards the upper surface  30  of the blade  22  to a larger degree than the upper surface  36  at the tip end. 
         [0092]    The extension rib  35  of this illustrated embodiment is block shaped (rectangular) when viewed from the side. Normally, the rear surface  38  will be angled rearwardly from the upper surface  36  to the attachment box  21 . Further, the extension rib  35  of this embodiment is of uniform thickness over its length. 
         [0093]    Normally, the tip end of the extension rib  35  of this embodiment is sharpened. The forward edge  42 , that is, the edge at the intersection of the forward surface  37  and the upper surface  36  of the extension rib  35  extends forwardly of the forward edge  29  of the blade member  22 . 
         [0094]    The outer forward edge of the extension rib extends downwardly and rearwardly to the blade member. The inner forward edge is located behind the outer forward edge or closer to the blade member  22 . Further, the upper forward edge is located in front of the lower forward edge. 
         [0095]    The result of the above edge configurations is that the extension rib  35  of this embodiment forms a forward point  45  and a sharpened, forward, outer edge on the extension rib. Typically, the rear surface  38  of the extension rib  35  of this embodiment is substantially parallel to the forward surface  37 . 
         [0096]    In  FIGS. 18 to 21 , a worn tooth of the first preferred embodiment, namely that illustrated in  FIGS. 4 ,  6  to  8  and  12  to  14 , is shown. It can be seen that the preferred edge configurations discussed above and the tooth shape in general, has contributed to the tooth retaining its overall shape and particularly the sharpened forward portions. 
         [0097]    In the present specification and claims (if any), the word “comprising” and its derivatives including “comprises” and “comprise” include each of the stated integers but does not exclude the inclusion of one or more further integers. 
         [0098]    Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations. 
         [0099]    In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art.