Patent Publication Number: US-2005132619-A1

Title: Excavating lip-mounted adapter and associated connection and shielding apparatus

Description:
BACKGROUND OF THE INVENTION  
      The present invention generally relates to excavating apparatus and, in representative embodiments thereof, more particularly provides improved excavating tooth adapters and associated techniques for operatively mounting them on the forward lower lip portion of an excavating device such as an excavating bucket.  
      Large excavating buckets, dippers or the like are typically provided with a spaced series of earth-cutting teeth which are each formed from two primary parts—a relatively large adapter and a relatively small replaceable point. The adapter has a rear base portion which is welded to a front portion of the excavating lip, and a forwardly projecting nose portion onto which the replaceable tooth point is removably secured by a suitable connecting pin or other connecting structure. Additionally, a series of replaceable lip protectors or shields may be interdigitated with the adapters, and suitably secured to the lip, to shield front edge portions of the lip between the adapters from operational abrasion wear.  
      One conventional type of bucket lip adapter is generally C-shaped and has upper and lower leg portions which respectively extend rearwardly along, and are welded along opposite side edge portions thereof to, top and bottom side portions of the lip. The interdigitated lip protectors extend beneath and shield the rearwardly extending lower adapter leg portions of the spaced adapters. In this conventional adapter/lip protector construction the positioning of portions of the lip protectors beneath the bottom adapter legs thickens the vertical dimension of the toothed excavating lip assembly in a manner undesirably lessening its earth penetration efficiency.  
      It is also known in the excavating art to utilize a lip adapter configuration in which the lower adapter leg portion is eliminated so that only an upper leg portion of the adapter extends rearwardly along the lip (i.e., an upper side portion thereof) and is surface welded thereto along the edge periphery of the upper adapter leg. While this reduces the vertical thickness of the toothed excavating lip assembly, it undesirably weakens the adapter/lip attachment strength. This is due to the fact that the weld area between the upper adapter leg and the top side of the lip (which provides substantially the entire adapter/lip attachment strength) is oriented in a manner such that the weld area is disposed in an exposed position above the top side of the lip and may be undesirably subjected to high tensile stresses during use of the excavating bucket.  
      As can readily be seen from the foregoing, a need exists for improved techniques and structures for operatively connecting adapters and associated lip protectors to an excavating lip structure. It is to this need that the present invention is directed.  
     SUMMARY OF THE INVENTION  
      In carrying out principles of the present invention, in accordance with illustrated embodiments thereof, specially designed excavating apparatus is provided which is representatively in the form of an excavating bucket having a blade or lip portion to which a series of wear members are secured in a mutually spaced relationship along the length of the lip. The lip has a top side, a bottom side and a front edge, and the wear members are representatively adapters having forwardly projecting nose portions to which replaceable tooth points may be removably secured, and lip protectors may be secured to the lip in various manners in an interdigitated relationship with the adapters to shield front lip edge portions between the adapters from operational abrasion wear. The adapters have bodies longitudinally extending transversely to the front edge of the lip and top portions extending rearwardly along the top side of the lip.  
      According to one aspect of the invention, each adapter is secured to the lip by cooperating mounting portions on the lip and the adapter disposed laterally outwardly of the adapter body and between the top and bottom sides of the lip, the cooperating mounting portions overlapping in a front-to-rear direction and being fixedly secured to one another, illustratively by welding. Preferably, the cooperating mounting portions are opposite side projections formed on each adapter and front side edge notches formed in the lip. The side projections or ears on the adapters are complementarily received and welded within the lip notches, which are preferably of semicircular shapes.  
      These front weld areas which secure the adapters to the lip do not appreciably project above the top side of the lip and, for the most part, are positioned laterally outwardly of their associated adapters. Accordingly, compared to conventional techniques for welding adapters to excavating lips, the present invention provides a stronger weld joint due to the fact that the front weld joints, during use of the bucket, are subjected primarily to shear stress instead of tensile stress, and also provide enhanced attachment strength due to their positioning in a laterally offset relationship with their associated adapters. According to further features of the invention, forwardly facing portions of these front weld areas may be shielded by portions of the adapter connector ears or (if lip protectors are installed) by portions of the lip protectors.  
      Preferably, no portion of any of the adapters extends rearwardly along the bottom side of the lip. Accordingly, the overall heights of the adapters are reduced, thereby desirably increasing the overall earth penetration efficiency of the bucket. Lip protectors installed between the adapters are illustratively configured to extend directly along the bottom side of the lip. Since the installed lip protectors are extended directly beneath the bottom side of the lip, without any adapter portion being interposed between the underside of the lip and associated lip protectors, the lip protectors may be vertically thicker and are thus desirably provided with longer operating lives since they may be permitted to wear away clear to the underside of the lip before having to be replaced.  
      According to another aspect of the invention, the lip protectors (if utilized) are operatively installed on the lip in a variety of representative novel manners. Utilizing one lip protector connection technique, telescoped connection portions are formed on the lip and lip protectors and have aligned fastening openings formed therein. A fastening structure extends through these aligned openings and removably intersecures these telescoped connection portions. In a second representative lip protector connection technique embodying principles of the present invention, the lip protectors extend along the bottom side of the lip and have openings therein which are aligned with openings in the lip. The lip protectors are captively retained on the lip by a fastening structure extending through these aligned openings.  
      In a third representative lip protector connection technique embodying principles of the present invention, the lip protectors extend along bottom sides of the lip and are supportingly interlocked with bottom side weldment structures on the bottom side of the lip. In a fourth representative lip protector connection technique embodying principles of the present invention, the adapters have underside recesses therein with upper walls having first fastening openings extending upwardly therethrough. The lip protectors have opposite ends with upturned tab portions with outer side recesses therein. Tab portions of lip protectors on facing ends of adjacent pairs of lip protectors project upwardly into the adapter underside recesses with the facing outer side recesses of each adjacent tab pair forming second fastening openings within the underside recesses in the adapters. Fastening structures extend through the first and second fastening openings and secure the lip protectors to the adapters. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a simplified, somewhat schematic perspective view of a portion of an excavating bucket embodying principles of the present invention;  
       FIG. 2  is an enlarged scale, somewhat more detailed assembled perspective view of part of a lip portion of the excavating bucket;  
       FIG. 3  is an exploded perspective view of the lip portion shown in  FIG. 2 ;  
       FIG. 4  is a top plan view of the lip portion shown in  FIG. 2 ;  
       FIG. 5  is a left side view of the lip portion shown in  FIG. 4 ;  
       FIG. 6  is a cross-sectional view through the lip portion taken along line  6 - 6  of  FIG. 4  with the point removed;  
       FIG. 7  is an assembled perspective view of part of a lip portion of a first alternate embodiment of the  FIG. 1  excavating bucket;  
       FIG. 8  is an exploded perspective view of the  FIG. 7  lip portion;  
       FIG. 9  is a top plan view of the  FIG. 7  lip portion;  
       FIG. 10  is a cross-sectional view taken through the  FIG. 9  lip portion along line  10 - 10  of  FIG. 9 ;  
       FIG. 11  is a cross-sectional view taken through the  FIG. 9  lip portion along line  11 - 11  of  FIG. 9 ;  
       FIG. 12  is a cross-sectional view taken through the  FIG. 9  lip portion along line  12 - 12  of  FIG. 9 ;  
       FIG. 13  is an assembled perspective view of part of a lip portion of a second alternate embodiment of the  FIG. 1  excavating bucket;  
       FIG. 14  is an exploded perspective view of the  FIG. 13  lip portion;  
       FIG. 15  is a top plan view of the  FIG. 13  lip portion;  
       FIG. 16  is a left side view of the lip portion shown in  FIG. 15 ;  
       FIG. 17  is a cross-sectional view taken through the  FIG. 15  lip portion along line  17 - 17  of  FIG. 15  with the point removed;  
       FIG. 18  is an assembled perspective view of part of a lip portion of a third alternate embodiment of the  FIG. 1  excavating bucket;  
       FIG. 19  is an exploded perspective view of the  FIG. 18  lip portion;  
       FIG. 20  is a bottom side perspective view of the  FIG. 18  lip portion;  
       FIG. 21  is a cross-sectional view through the  FIG. 18  lip portion taken along line  21 - 21  of  FIG. 18 ;  
       FIG. 22  is a partially exploded perspective view of part of a lip portion of a fourth alternate embodiment of the  FIG. 1  excavating bucket;  
       FIG. 23  is an enlarged scale perspective view of an adapter removed from the  FIG. 22  lip portion; and  
       FIG. 24  is a cross-sectional view through the  FIG. 23  adapter taken along line  24 - 24  of  FIG. 23 . 
    
    
     DETAILED DESCRIPTION  
      In one embodiment thereof, the present invention provides excavation apparatus representatively in the form of an excavating bucket  10 , a portion of which is shown in simplified, partially exploded perspective form in  FIG. 1 . Bucket  10  has a bottom side wall  12  to a forward edge portion of which an elongated, plate-shaped blade or lip  14  is suitably anchored. As illustrated in  FIG. 2 , the top side of the lip  14  is substantially planar and forwardly extends to a transverse front edge surface  15  of the lip  14 . A spaced series of wear members representatively in the form of adapters  16  are anchored to the lip  14  and have forwardly projecting nose portions  18  to which replaceable excavating tooth points  20  may be removably secured. Lip protector or shield structures  22  are interdigitated with the adapter/point assemblies  16 , 20  and are removably secured to the lip  14 .  
      According to key aspects thereof, the present invention provides novel attachment structure and apparatus for securing the interdigitated adapters  16  and lip protectors  22  to the lip  14 . Portions of five representative embodiments of the bucket  10  are shown—(1) a first embodiment  10  shown in  FIGS. 1-6 ; (2) a second embodiment  10   a  shown in  FIGS. 7-12 ; (3) a third embodiment  10   b  shown in  FIGS. 13-17 ; (4) a fourth embodiment  10   c  shown in  FIGS. 18-21 ; and (5) a fifth embodiment  10   d  shown in  FIGS. 22-24 . For ease in comparison of these five excavating bucket embodiments, components in the embodiments  10   a - 10   d  similar to those in embodiment  10  have been given identical reference numerals respectively having the subscripts “a”, “b”, “c” and “d”.  
      Referring initially to  FIGS. 1-6 , a key feature of the invention, incorporated in all five illustrated embodiments thereof, is the method by which the adapters  16  are secured to the excavating lip  14 . Importantly, the installed adapters  16  do not have any portions which underlie and extend rearwardly along the bottom side of the lip  14 . This advantageously reduces the vertical thickness of the each adapter  16  to thereby improve the excavation efficiency of the bucket  10 . To effect the securement of the adapters  16  to the lip  14 , a spaced series of notches  24  (representatively having semi-circular shapes) are formed in the front edge of the lip  14  (see  FIGS. 2-4 ) and complementarily receive outwardly projecting ears  26  formed on horizontally opposite sides of a bottom front portion of each adapter  16 . Ears  26  are welded to the lip  14 , as at  28 , along interior side surface portions of the notches  24 , in a manner such that (1) the weld areas  28  do not upwardly project appreciably beyond the top side of the lip  14 , and (2) the weld areas  28  are, for the most part spaced laterally outwardly from opposite sides of the elongated body of the adapter  16 . The portion of each adapter  16  disposed rearwardly of the weld areas  28  is welded in a conventional manner along its periphery to the top side of the lip  14 . As stated previously, this novel adapter-to-lip securement technique is also employed in the bucket embodiment  10   a  illustrated in  FIGS. 7-12 ; the bucket embodiment  10   b  illustrated in  FIGS. 13-17 ; the bucket embodiment  10   c  illustrated in  FIGS. 18-21 ; and the bucket embodiment  10   d  illustrated in  FIGS. 22-24 .  
      While ear portions  26  on the adapters  16  are representatively shown as being received and welded within corresponding notches or recesses  24  in the front edge surface of the lip  14 , other forms of cooperating mounting portions on the lip  14  and adapters  16  (disposed laterally outwardly of the adapters and between the top and bottom sides of the lip, interlocked in a forward-to rearward direction and fixedly secured to one another) could be utilized if desired in any of the representatively illustrated bucket embodiments  10 - 10   d . As but one example of this alternative cooperating mounting portion structure embodying principles of the present invention, instead of having portions of the adapters  16  received and welded within notches  24  on the front edge of the lip  14 , the front edge of the lip  14  could have horizontally spaced apart front projections which are received and welded within corresponding recesses or notches suitably formed in the adapters.  
      With continuing reference to the bucket embodiment  10  shown in  FIGS. 1-6 , each lip protector  22  has a generally flat base portion  30  which underlies the bottom side of the lip  14 , and a generally wedge-shape leading edge portion  32  which extends forwardly from the front edge of the lip  14 . Each lip protector  22  is removably installed on the lip  14 , between an adjacent pair of adapters  16  (prior to the installation of tooth points  20  thereon) by rearwardly moving the protector base  30  beneath the bottom side of the lip  14  until (1) opposite side edge recesses  34  on the base  30  (see  FIG. 3 ) receive opposing side edge portions of a spaced pair of bottom side support weldments  36  on the lip  14  (see  FIGS. 4 and 5 ), and (2) forwardly projecting adapter ear extensions  38  (see  FIGS. 2 and 3 ) enter corresponding recesses  40  on the rear side of the leading lip protector edge portion  32  (see  FIGS. 3 and 5 ).  
      Next, the hollow tooth points  20  are telescoped onto their associated adapter noses  18  and captives retained thereon by suitable connector pins  42  (see  FIG. 5 ) installed in aligned point and adapter nose openings  44 , 46  (see  FIG. 6 ). Rearwardly facing lower side surface portions  48  in the installed tooth points  20  (see  FIG. 3 ) forwardly overlie corresponding abutment surfaces  50  on the lip protectors  22 , as also shown in  FIG. 3 , to prevent forward removal of the lip protectors  22  from between the adjacent pairs of adapter/point assemblies  16 , 20 .  
      As can best be seen in  FIGS. 4-6 , the installed adapters  16  do not underlie and extend rearwardly along the bottom side of the lip  14 , the installed lip protectors  22  are releasably interlocked with the bottom side support weldments  36  and with portions of the adapters  16 , and the installed lip protectors  22  are blocked against forward removal by the installed tooth points  20 .  
      In the second representative bucket embodiment  10   a  shown in  FIGS. 7-12 , in which the tooth points have been removed and are not illustrated, the previously described adapter ear extensions  38 , lip protector recesses  40 , and lip protector abutment surfaces  50  are deleted. Between each adjacent pair of adapters  16   a  a semicircular front edge recess  52  is formed, and a correspondingly shaped metal insert plate  54  (see  FIGS. 8 and 10 ) is welded into place within a lower side portion of the recess  52 . A rearwardly projecting securement tab  56  (see  FIGS. 7-9 ) is formed on a rear upper side section of the leading edge portion  32   a  of the lip protector  22   a . When the lip protector  22   a  is rearwardly moved into place between an adjacent pair of adapters  16   a , and interlocks with a pair of the bottom side support weldments  36   a  on the lip  14   a , the tab  56  is complementarily received in the lip recess  52  above the insert plate  54 . The received tab  56  is removably anchored in place within the lip recess  52  by a suitable connector pin structure  58  (see  FIGS. 7-10 ) inserted into aligned openings  60 , 62  respectively formed in the plate  54  and tab  56 . The inserted pin  58  thus releasably prevents forward removal from the lip  14   a  of the installed lip protector  22   a.    
      In the third representative bucket embodiment  10   b  shown in  FIGS. 13-17 , each lip protector  22   b  is again provided with the previously described forward abutment surfaces  50   b  which rearwardly overlie corresponding blocking surfaces  48   b  on the installed tooth points  20   b , and the recesses  40   b  which receive forwardly projecting ear extensions  38   b  on the adapters  16   b . However, in this bucket embodiment the bottom side weldments  36 , and corresponding lip protector recesses  34  are eliminated, and a bolt  64  and nut  66  are used in place of the previously described connector pin  58  to anchor the installed lip protector  22   b  to the lip  14   b . With the lip protector base  30   b  in place beneath the lip  14   b , the bolt  64  is extended upwardly through aligned openings  68  and  70 , respectively formed in a connection tab  72  on the lip protector base  30   b , and upwardly through the lip  14   b , and threaded into the nut  66 . In this bucket embodiment the previously described bottom side lip weldments  36 , and the corresponding rear side edge recesses  34  in the lip protector base, are eliminated.  
      In the fourth representative bucket embodiment  10   c  shown in FIGS;  18 - 21 , the previously described bottom lip side support weldments  36  and associated lip protector side edge recesses  40  are eliminated. The forwardly projecting adapter ear extensions  38   c , which are received in the lip protector recesses  40   c , are widened in a manner such that they extend horizontally across front side surfaces of the lip weld areas  28   c.    
      Each adapter  16   c , rearwardly of its nose portion  18   c , has an underside cavity  74  (see  FIG. 21 ) from a rear side portion of which a circularly cross-sectioned opening  76  extends in a rearwardly and upwardly sloped direction. An enlarged, hexagonally cross-sectioned upper end portion  78  of the opening  76  extends outwardly through a rear top side portion of the adapter  16   c . Accordingly, an upwardly facing ledge surface  80  (see  FIG. 21 ) is formed at the juncture of the opening portions  76 , 78 .  
      The opposite ends of each lip protector  22   c  have forwardly facing, generally planar abutment surfaces  82  which, in the assembled bucket structure  10   c  cross-sectionally depicted in  FIG. 21 , rearwardly overlie rear end surface portions  84  of the installed tooth points  20   c . Positioned rearwardly of abutment surfaces  82  of each lip protector  22   c  are upstanding tabs  86  (see  FIGS. 19 and 21 ) having oppositely facing outer side surfaces  88 . Generally semicircularly cross-sectioned recesses  90  are formed in the side surfaces  88  and have narrowed upper end portions  92  that form downwardly facing semicircular ledges  94  in the recesses  90 .  
      With the adapters  16   c  operatively installed on the lip  14 C, the lip protectors  22   c  interdigitated therewith are installed by positioning their body portions  30   c  (see  FIGS. 20 and 21 ) beneath the bottom side of the lip  14 C in a manner such that the upstanding tabs  86  on facing ends of each adjacent pair of lip protectors  22   c  upwardly enter the bottom side recess  74  of the adapter  16   c  disposed between the lip protector pair, and the forward adapter ear extensions  38   c  (see  FIGS. 18 and 19 ) enter the lip protector recesses  40   c  (see  FIG. 19 ). The facing recesses  90  on each adjacent pair of tabs  86  together form a generally circular opening area  90 , 90  that underlies the opening  76  in the associated adapter  16   c.    
      To captively and removably retain the installed lip protectors  22   c  on the lip  14   c , at each adapter  16   c  a bolt  96  (see  FIGS. 19-21 ) is extended upwardly through each lip protector end opening pair  90 , 90  in a manner such that the bold head  97  upwardly engages the end opening ledges  94 , 94  (see  FIGS. 19-21 ) and the bolt  96  is threaded into a nut  98  (see  FIGS. 19 and 21 ) nonrotatably received in the hex end portion  78  of the adapter opening  76 . Next, the tooth points  20   c  are removably installed on the adapter noses  18   c  (see  FIGS. 19 and 21 ) so that the rear point end surfaces  84  forwardly block the lip protector abutment surfaces  82  (see  FIGS. 19-21 ). As schematically depicted in phantom in  FIG. 21 , a suitable wear protector shroud or cap  100  may be mounted on the top side of each installed adapter  16   c  (as well as on the adapters of the various other bucket embodiments representatively illustrated and described herein. Not only do the illustrated wear protector shrouds  100  shield the top sides of the adapters  16   c  from abrasion wear, but they also serve to captively retain the nuts  98  within the adapter hex opening  78  to prevent movement of the nuts  98  outwardly through their upper ends.  
      The fifth representative bucket embodiment  10   d  shown in  FIGS. 22-24  is similar to the previously described fourth bucket embodiment  10   c , but without lip protectors  22  being utilized (although various types of lip protectors could be installed between adjacent adapter pairs if desired). Adapters  16   d  are illustratively similar to the previously described adapters  16   c , but the adapter ears  26   d  are not provided with forward extensions similar to the previously described extensions  38 . Moreover, the top side of front lip edge  102  is downwardly sloped instead of being perpendicular to the top and bottom sides of the lip  10   d . To accommodate this front lip edge slope, outer side surface portions  104 , 106  of the adapter ears  26   d  (see  FIG. 23 ) are correspondingly sloped.  
      Compared to conventional adapter-to-lip construction techniques, the connection of the previously described adapters to their associated lip structures using transverse adapter ears complementarily received and welded in corresponding front lip edge notches provides substantially greater adapter weld strength at the front edge of the lip since the front adapter weld portions are laterally offset from their associated adapters. Additionally, since these front weld areas do not project upwardly beyond the top side of the lip, and (in bucket embodiments  10 - 10   c ) have forwardly facing front surface areas which are shielded by either portions of their associated adapters or by adjacent lip protectors, they are subjected to a desirably lesser degree of abrasion wear during use of their associated excavating buckets. Moreover, these front adapter weld areas are primarily exposed to shear stresses instead of tensile stresses which they are less capable of withstanding.  
      Further, since the adapters shown in the representatively illustrated bucket embodiments  10 - 10   d  are devoid of bottom legs which extend rearwardly along bottom sides of their associated lips, the lip protectors (when used) may upwardly extend clear to the bottom side of the lip in stead of being spaced downwardly apart therefrom by a bottom adapter leg interposed between the lip protector and the bottom side of the lip. For the end user, this advantageously results in a longer operating life for the lip protectors, since they can wear away clear up to the bottom side of excavator lip which they shield from operational excavation abrasion and wear before they need to be replaced.  
      The foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims.