Abstract:
A wear assembly to protect the front edge of an excavating bucket, which is secure, stable, easy to use, readily manufactured, and provides increased safety, and which eliminates any need for holes to be formed in the lip. The wear assembly includes a wear member that has a pair of legs to straddle the front edge of the bucket. One of the legs defines an axial slot, which has opposing grooves for receiving rails of a boss fixed to the bucket. The grooves narrow in a forward direction to permit easier installation and removal of the wear member, to permit use of side wings without interference from adjacent wear parts, and to enable enhanced resistance under some loads.

Description:
[0001]     This application is a continuation-in-part of co-pending U.S. patent application Ser. No. 11/529,447 filed Sep. 28, 2006, which in turn is a divisional application of U.S. patent application Ser. No. 10/812,348 filed Mar. 30, 2004. 
     
    
     THE FIELD OF THE INVENTION  
       [0002]     The present invention pertains to a wear assembly for an excavating bucket.  
       THE BACKGROUND OF THE INVENTION  
       [0003]     Excavating buckets for earth working equipment are typically subjected to harsh conditions. A series of wear members are usually provided along the lip of the bucket to improve the digging operation and protect against wear. Wear members have in the past been welded or mechanically secured in many different ways. Nevertheless, there is a need for an improved wear assembly in these environments.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention pertains to an improved wear assembly for protecting an excavating bucket from wear, which is secure, stable, easy to use, readily manufactured, and provides increased safety. The present invention further eliminates any need for holes to be formed in the lip.  
         [0005]     In accordance with one aspect of the invention, the wear assembly includes a wear member provided with a connector in the form of a tongue or slot which has rails or grooves, respectively, to couple with a complementary connector on a boss fixed to the bucket. The rails or grooves are formed with a curved and/or narrowing configuration to ease installation and removal of the wear member, permit the use of wings to better protect adjacent parts, and better resist some loads.  
         [0006]     In accordance with another aspect of the invention, the wear member includes an interior which wraps about the front edge of the bucket and a boss fixed to the bucket. The interior has a first recess with a first set of opposed sidewalls to receive an upstanding support on a boss, and a second recess with a second set of opposed sidewalls spaced farther apart than the first set of opposed sidewalls to receive the sides of the boss. By using two sets of recesses, the wear member is more stably mounted and better able to resist side loads.  
         [0007]     In accordance with another aspect of the invention, the wear member includes laterally extending wings to overlie adjacent parts, e.g., an adapter, attached to the lip to provide additional protection. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]      FIG. 1  is a perspective view of a wear member straddling a lip of a bucket in accordance with the present invention.  
         [0009]      FIG. 2  is a front perspective view of a wear member of the invention.  
         [0010]      FIG. 3  is a front perspective view of an alternative wear member.  
         [0011]      FIG. 4  is a partial perspective view from the bottom of a lip with the alternative wear member.  
         [0012]      FIG. 5  is a rear perspective view of the wear member of the invention.  
         [0013]      FIG. 6  is a side view of the wear member.  
         [0014]      FIG. 7  is a rear view of the wear member.  
         [0015]      FIG. 8  is a front perspective view of a boss of the present invention.  
         [0016]      FIG. 9  is a rear perspective view of the boss.  
         [0017]      FIG. 10  is a side view of the boss.  
         [0018]      FIG. 11  is a perspective view of a lock of the present invention.  
         [0019]      FIG. 12  is an exploded, perspective view of the lock. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0020]     The present invention pertains to a wear assembly  10  for an excavating bucket. While wear assembly  10  is particularly suited for securing a wear member  15  in the form of a shroud to a lip of a bucket, it could also be used to secure other kinds of wear members (e.g., wings or adapters) to the bucket. In a typical bucket, lip  16  includes an inner face  17 , an outer face  18  and a front edge  19 . Although the illustrated lip ( FIG. 1 ) shows the inner face  17  with a ramp surface  17   a , the invention can be used with other kinds of lips.  
         [0021]     The invention is at times described in relative terms, such as forward, rearward, up, down, vertical, horizontal, etc. to ease understanding of the invention. These terms are generally to be considered relative to the orientation of the components in  FIG. 1  (unless otherwise noted), and are not to be considered limitations on the invention. As can be appreciated, the wear member can be used and oriented in a variety of ways.  
         [0022]     A boss or base  20  ( FIGS. 8-10 ) has a pair of legs  21 ,  22  that straddle the lip  16  about front edge  19 . Although first leg  21  is preferably the outer leg and second leg  22  the inner leg, they could be reversed. In the illustrated embodiment, the first or outer leg  21  has an inner surface  23  that sets against and extends along outer face  18  of lip  16 . In the preferred construction, first leg  21  includes holes  27  to facilitate welding of the boss to the lip. In this embodiment, welding is also provided along brace  30  and grooves  31  at the end of second leg  22 . While boss  20  is preferably welded to the lip, it could be formed (e.g., cast or forged) as an integral part of the lip or secured by mechanical means. In addition, the boss could be formed as a multiple of parts, which are integral or spaced apart, although a one-piece member is preferred for simplicity and strength.  
         [0023]     Outer leg  21  includes a connector  28  that couples to a complementary connector  29  on wear member  15 . In the illustrated embodiment, connector  28  is formed as rails  24  extending axially along sidewalls  26  of the boss ( FIGS. 9 and 10 ). The rails project laterally outward from each sidewall  26  to define a generally inverted T-shaped cross-section, though other shapes are possible. Rails  24  include holding surfaces  25  that are offset from inner surface  23  so as to be spaced from the outer face  18  of the bucket which it faces.  
         [0024]     A brace  30  preferably extends laterally across the rear end of first leg  21  ( FIGS. 8-10 ). The rear ends  44  of rails  24  are preferably fixed to brace  30  to provide additional support to the rails when under load. Such support at the rear end of the rails is particularly advantageous in resisting vertical loads that tend to rotate or swing the wear member about the front edge of the lip. Brace  30  preferably extends outward of first leg  21  to define a stop surface  32  adapted to abut a rear end  40  of wear member  15  and thereby reduce the stress on the boss, which in turn, reduces the stress along front edge  19  of lip  16 .  
         [0025]     A front end  45  of boss  20  wraps around front edge  19  of lip  16 . The interior  46  of boss  20  (i.e., the surface that faces lip  16 ) is shaped to generally conform to the shape of the particular lip to which it is fixed. In the illustrated embodiment, the interior  46  of boss  20  includes a corner surface  47  that sets against front edge  19 , an inner surface  48  of second leg  22  that sets against ramp  17   a , and inner surface  23  of first leg  21  that sets against outer face  18 . The inner or second leg  22  preferably overlies only ramp surface  17   a  so that the boss is outside or below the inner face  17  to avoid impeding the gathering or dumping of the excavated material, but could extend along inner  17  rearward of ramp  17 A. Also, other arrangements for attaching the boss are possible. For other kinds of lips, the interior would preferably be changed to generally match the lip profile.  
         [0026]     The front face  49  of boss  20  preferably has a uniform curved shape to provide a smooth surface without corners to act as a thrust bearing face for wear member  15 . In this way, the boss is able to provide a better bearing surface than the front of lip  16  with its relatively sharp and thinner front edge  19 . Nevertheless, other shapes for front face  49  are possible. Inner leg  22  preferably includes an upstanding support  50  that forms an abutment for lock  56  ( FIGS. 8-10 ). Support  50  includes a rear wall  52  to abut lock  56 , a pair of sidewalls  94  and an upper inclined wall  54  that extends upward from front face  49 .  
         [0027]     Wear member  15  has a front end  66  and a rear end  70  that is bifurcated to define an outer or first leg  71  and an inner or second leg  72  ( FIGS. 1-2  and  5 - 6 ). In use, wear member  15  overlies and straddles lip  16  and boss  20 . As a result, boss  20  is largely shielded from the movement of abrasive earthen material passing over the component. Wear member  15  includes an interior  85  that includes inner face  80  of outer leg  71 , inner face  87  of inner leg  72 , and an inner corner surface  89  at the intersection of legs  71 ,  72  ( FIGS. 5 and 6 ). Inner corner surface  89  has a shape that generally matches front face  49  of boss  20  to abut against it. Accordingly, in the preferred embodiment, inner corner surface  89  has a generally uniform curved surface. Outer leg  71  has a generally flat outer face  76  and a rear deflector face  77  that is inclined forwardly away from lip  16  to direct earthen material away from the wear member during reverse movement of the bucket. Wear member  15   a  also optionally includes wings  75  that project laterally, preferably from outer leg  71   a , to overlie the adjacent wear parts  78  (e.g., adapters) and provide additional protection to the adjacent wear parts  78  ( FIGS. 3 and 4 ). Wings  75  are offset from inner face  80   a  of outer leg  71   a  (i.e., spaced further from lip  16 ) to define clearance for the adjacent wear parts  78  when wear member  15   a  is fully seated on boss  20 .  
         [0028]     Connector  29  of wear member  15  extends along outer leg  21  in the form of a slot  34 ; i.e., dogleg flanges  35  extend along the inner surface  80  of outer leg  71  to define slot  34  (although slot  34  could be formed in other ways). Grooves  37  are preferably defined by inner surface  80  of outer leg  71  and retaining surface  38  on flange  35 . Rails  24  are received into side grooves  37  along flanges  35  such that the distal ends  39  of flanges  35  are received between rails  24  and outer surface  18  with retaining surfaces  38  opposed to holding surfaces  25 . Alternatively, connectors  28 ,  29  could be reversed with a tongue having rails formed on the wear member  15  and a slot having side grooves to be formed on the boss  20 .  
         [0029]     Holding surfaces  25  of rails  24  are preferably curved to have a convex shape, and retaining surfaces  38  a complementary concave shape. This curve results in a narrowing of the rail as it extends forwardly. This narrowing of rails  24  allows wear member  15  to be fed onto boss  20  more easily; i.e., grooves  37  are wider at the rear end  40  of wear member  15  as compared to the narrow front ends  41  of rails  24 . As a result, the wear member can be tilted at various angles when it is initially fed onto the rails  24  and then directed into the right orientation by the widening of the rails. Moreover, if the wear member is formed with lateral wings, as discussed below, the narrowing rails permit the wear member  15  to be purposefully titled at an angle to permit the wings to clear the adjacent components as wear member  15  is fed onto boss  20 . The narrowing of rails  24  and grooves  37  also enables easier release of wear member  15  as rails and grooves are not slid along each other surfaces after initial release. Further, the corresponding curved portions  42 ,  43  on holding surface  25  and retaining surface  38  (surfaces  25 ,  38  could be curved their entire length or only at the front ends) resist certain vertical loads at a more perpendicular orientation and provide a stronger and more stable resistance. As alternatives, rails  24  and grooves  37  could narrow without curved surfaces to achieve some of the benefits of the invention. In addition, the entire rail could be curved. Also, the holding surface could have an inclined but linear configuration such that the rail narrows as it extended forward, but is not curved.  
         [0030]     Inner face  87  of inner leg  72  includes a first recess  91  into which upstanding support  50  is received, and a second recess  92  into which the width of boss  20  is received. The first recess  91  includes a pair of opposed sidewalls  93  to bracket the sides  94  of support  50 . The second recess  92  includes a pair of opposed sidewalls  95 , spaced farther apart than sidewalls  93 , to receive the entire width of boss  20 . By using this double set of recesses  91 ,  92 , the wear member  15  is more stably mounted on boss  20  and better able to resist side loads.  
         [0031]     When wear member  15  is installed, it is slid over boss  20  such that inner and outer legs  71 ,  72  straddle the lip ( FIGS. 1-4 ). Rails  24  are fit within grooves  37  as shroud  15  is moved rearward. As discussed above, wear member  15  can be tilted at various angles and still fit onto the rails for easier installation. The rearward movement of shroud  15  is continued until inside corner surface  89  abuts front face  49  of boss  20 . At this juncture, rear ends  33  of flanges  35  of outer leg  71  are preferably placed in close proximity to stop surface  32 . With new cast parts, it is not practical for inside corner surface  89  and rear ends  33  to simultaneously abut front face  49  and stop surface  32 , respectively. However, by placing rear ends  33  in close proximity with stop surface  32 , the two surfaces will typically abut after a short amount of time as wear develops in the parts or under heavy loading to provide extra support to the shroud and provide enhanced protection for the lip. Outer leg  71  overlies outer leg  21  of boss  20  and outer face  18  of lip  16 , and inner leg  72  overlies inner leg  22  of boss  20  and ramp surface  17   a  of lip  16 . Inner leg  72 , along inner surface  87 , includes two sets of side surfaces  93 ,  95 . Support  50  fits within recess  91  and the entire boss  20  fits within recess  92  for enhanced support and stability.  
         [0032]     Inner leg  72  includes an aperture  86  adapted to receive lock  56 . In the preferred embodiment, aperture  86  has a main portion  90  having a generally rectangular configuration to match the shape of the preferred lock, though other shapes are possible, and a stem portion  97  that opens in the rear wall  98  of inner leg  72  to provide clearance for plug member  58 . The rear wall  88  of aperture  86  forms a bearing surface to each side of stem portion  92  to abut lock  56 .  
         [0033]     In the preferred construction, lock  56  includes a body  101  having a generally parallelepiped configuration that corresponds to the shape of aperture  86  ( FIGS. 8-11 ), though other shapes can be used. The body includes a front wall  103 , a rear wall  104 , and sidewalls  105 ,  106 . A threaded bore  109  extends through body  101  and opens in front and rear walls  103 ,  104 . Plug member  58  includes a threaded shank  111  to be threaded into bore  109 , and a tool-engaging formation  113  on rear end  115 . While in the preferred construction formation  113  is formed as a hex-shaped socket, the socket could have other shapes or be replaced with other kinds of flats adapted to cooperate with tools to effect turning of the plug. The front end  117  of plug  58  is adapted to project forward and abut rear wall  52  of support  50 . A recess  57  is preferably formed in front wall  53  of aperture  86  to give clearance for the mount of plug  58 . In this way, the assembly has a more compact profile. Plug member  58  can be advanced so as to push against rear wall  52  of support  50 , which in turn, presses rear wall  104  of lock  56  against rear wall  88  of aperture  86 . This movement of plug member  58 , then, causes shroud  15  to be pushed tightly against front face  49  of boss  20 . A tighter fit reduces the shifting of the shroud during use, which will in turn reduce the amount of wearing among the components. Nevertheless, a lock without an adjustment assembly could also be used.  
         [0034]     A retainer  121  is also preferably provided to resist unintended loosening of plug member  58 . In the preferred construction, retainer  121  includes a threaded bolt  123  and a retaining ring  125 . Retaining ring  125  has a non-circular internal hole  127  that matches the exterior of head  113  of plug member  58 , which is preferably a hex shape. The bolt  123  has a threaded shank  131  that threads into a second threaded bore  133  and a head  135  that tightens against retaining ring  125  to prevent its rotation. Of course, other retainers could also be used.  
         [0035]     When shroud  15  is fit onto lip  16 , the front wall  53  of aperture  86  is generally aligned with rear wall  52  of support  50 , though it could also be spaced rearward thereof, to permit lock  56  to fit within aperture  86  and be rearward of support  50 . In this way, front wall  103  of lock  56  opposes rear wall  52  of support  50 . As plug member  58  is advanced to engage rear wall  52 , it preferably extends underneath leg  72 . In this way, plug member  58  not only functions as a take up member to tighten the fit of the shroud against the boss, it also functions as a latch to hold the lock in aperture  86 . Moreover, since the rear end  115  of plug member  58  sets within stem portion  92  (which can be easily cleared) the plug member can be easily retracted to remove the lock without concern over impacted fines blocking the movement.  
         [0036]     In the preferred construction, one sidewall  105  of lock body  101  has an arcuate shape to fit against an arcuate sidewall  127  of aperture  86  so that the lock can be easily swung into aperture  86  ( FIG. 10 ). Of course, other locks could be used to secure wear member  15  to boss  20 .