Patent Abstract:
A tip for demolition and construction equipment has a discrete base with at least one recess therein to accept a replaceable insert. The insert has a projection that fits within a mating socket within the base. A threaded bolt may extend through a common bore within the insert and base to secure the insert to the base. The tip may also include a second opposing insert which is held within a respective recess by a common bolt. Finally, each insert may have a key which interlocks within a keyway of the base recess to securely hold the insert within the base and to distribute forces created by a cutting operation over a greater area.

Full Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a tip used for construction or demolition equipment which is adapted to be attached to a support and used in conjunction with, for example, a heavy-duty metal cutting shear, a plate shear, a concrete crusher, a grapple, or other construction or demolition equipment. More particularly, the present invention relates to a replaceable tip secured to a support. 
     2. Description of Related Art 
     For purposes of discussion herein, demolition and construction equipment may also be referred to as scrap handling equipment. The description of demolition equipment and construction equipment herein is not intended to be restrictive of the equipment being referenced. Demolition equipment, such as heavy-duty metal cutting shears, grapples, and concrete crushers are mounted on backhoes powered by hydraulic cylinders for a variety of jobs in the demolition field. This equipment provides for the efficient cutting and handling of scrap. For example, in the dismantling of an industrial building, metal scrap, in the form of various diameter pipes, structural I-beams, channels, angles, sheet metal plates, and the like must be efficiently severed and handled by heavy duty metal shears. Such shears can also be utilized for reducing automobiles, truck frames, railroad cars, and the like. The shears must be able to move and cut the metal scrap pieces regardless of the size or shape of the individual scrap pieces and without any significant damage to the shears. In the demolition of an industrial building, concrete crushing devices, such as a concrete pulverizer or concrete crackers, are also used to reduce the structure to manageable components which can be easily handled and removed from the site. Wood shears and plate shears also represent specialized cutting devices useful in particular demolition or debris removal situations depending on the type of scrap. Also, a grapple is often utilized where handling of debris or work pieces is a primary function of the equipment. Historically, all of these pieces of equipment represent distinct tools having significant independent capital cost. Consequently, the demolition industry has tended to develop one type of tool that can be used for as many of these applications as possible. 
     For illustrative purposes, the following discussion will be directed to metal shears. One type of metal shear is a shear having a fixed blade and a movable blade pivoted thereto. The movable blade is pivoted by a hydraulic cylinder to provide a shearing action between the blades for severing the work pieces. Examples of this type of shears can be found in prior U.S. Pat. Nos. 4,403,431; 4,670,983; 4,897,921; 5,926,958; and 5,940,971 which are assigned to the Assignee of this application and which are herein incorporated in their entirety by reference. 
       FIG. 1  illustrates a prior art, multiple tool attachment adapted to be attached to demolition or construction equipment, such as a backhoe (not shown). The multiple tool attachment is adapted to connect one of a series of tools or tool units to the demolition equipment. The tool attached in  FIG. 1  is a metal shear  10 . The shear  10  includes a first blade  12  connected to an upper jaw  13  and a second blade  14  connected to a lower jaw  15 , wherein the jaws  13 ,  15  are pivotally connected at a hub or main pin  16  to a universal body  18 . The body  18  is referred to as universal because it remains common to a series of tools or tool units in the attachment system. The universal body  18  is comprised of sides  19 , a bearing housing  20 , and a yoke  21 . 
     The upper jaw  13  and the lower jaw  15  pivot about the main pin  16  to form a movable jaw assembly  22 . At the end of the first blade  12  is a blade tip  24 . Details of the blade tip  24  are provided in  FIGS. 3 and 4 , wherein the blade tip  24  is comprised of a base  26  having a top side  28 , bottom side  30 , and walls  32 ,  34  therebetween. The base  26  of the blade tip  24  is a completely solid piece and the top side  28  of the base  26  is secured to a support  36  associated with the upper jaw  13 . 
     Directing attention to  FIGS. 1 and 2 , the second blade  14  has associated with it a guide channel  38  which accepts and provides lateral support to the blade tip  24  and the first blade  12 . To minimize the deflection experienced under load by the first blade  12  and the blade tip  24 , the tolerance for the guide channel  38  is fairly low. 
     In many applications, the first blade  12  and support  36  may be laterally displaced relative to the guide channel  38 , such that upon entering the guide channel  38  the side of the blade tip  24  experiences rubbing and extensive wear during normal operation. This wear, if not properly maintained, can lead to the first blade  12  becoming jammed or stuck in the guide channel  38 . This condition is known as “stickers” in the industry. Stickers can develop when the clearance gap between the walls  32 ,  34  of the tip  24  of the first blade  12  and the walls  40 ,  42  of the guide channel  38  of the lower blade  14  become excessive enough to allow material to become wedged between these surfaces while shearing. Once the first blade  12  becomes stuck within the guide channel  38 , the shear  10  must oftentimes be decommissioned for repair. It is then necessary to build up the walls  32 ,  34  of the tip  24  by welding to keep these gaps at a minimum. This process is very time consuming and costly and, depending on the material that the shear is processing, building up the tip could be required as often as once a week. 
       FIG. 5  illustrates a prior art design of a blade tip  100  having a base  114  with a recess  132  to accept replaceable inserts  150 ,  185 . Each insert, for example insert  150 , has a generally planar top side  152  that mates with the upper side  134  of the recess  132 . Additionally, non-circular projections  168  extend from the inserts  150  and fit within matching sockets  166  within the base  114 . A common bore  170  extends through the insert  150 , the base  114 , and an opposing insert  185 . A fastener  172  passes through the common bore  170  and secures the inserts  150 ,  185  within their respective recesses  132 ,  182 . The fastener  172  may be a threaded bolt having a bolt head  174  and a threaded shaft  176  mated with a threaded nut  186 . 
     A tip design is desired that may be easily repaired or replaced when worn to minimize the down time of a shear or other equipment. 
     Furthermore, a tip design is desired to more uniformly distribute the load generated by cutting forces on the inserts  150 ,  185  to the base  114 . 
     SUMMARY OF THE INVENTION 
     A tip for demolition and construction equipment comprising discrete base having a top side, a bottom side, a front side, and walls therebetween; a generally planar mounting surface on the top side of the base adapted to be secured to a support; a central portion with a cutting edge, whereby the cutting edge is defined at the lowermost portion of the bottom side of the base at the intersection with the front side; and a recess extending into at least one wall of the base, wherein the recess defines a recess upper side, an inner wall and a recess contour; wherein the recess upper side has generally planar sections and extends in a direction parallel to the mounting surface and; wherein the recess further includes a keyway adjacent to the generally planar sections of the upper side; and an insert having a top side, a bottom side, a front side, and walls therebetween; a cutting edge defined at the lowermost portion of the bottom side of the insert at the intersection with the front side; and a profile which generally conforms to the recess contour, wherein the top side has generally planar sections and further includes a key protruding from and adjacent to the generally planar sections of the top side; and wherein an insert is secured within each recess such that the top side of the insert mates with the upper side of the recess and wherein the keyway is engaged by the key to provide an interlocking arrangement between the base and the insert. 
     An insert for use with a tip for demolition or construction equipment, wherein the tip has a discrete base with a top side, a bottom side and walls therebetween, a mounting surface on the top side of the base adapted to be secured to a support, a central portion with a cutting edge, whereby the cutting edge is defined at the lowermost portion of the bottom side of the base, and a recess extending into at least one side of the base, wherein the recess defines at least a recess upper wall, an inner side and a recess contour, wherein the insert comprises a body having a top side, a bottom side, a front side and walls therebetween; a cutting edge defined at the intersection of two walls; and a profile which generally conforms to the recess contour, wherein the top side has generally planar sections and further includes a key protruding from and adjacent to the generally planar sections of the top side, wherein the keyway is comprised of a radiussed segment within the base, wherein the segment has at an end closest to the front side a terminal defined by a radial line forming a front angle F of between 1-90 degrees with the generally planar mounting sections and having an end furthest from the front side a terminal defined by a radial line forming a back angle B of between 180 and 270 degrees with the generally planar mounting sections. 
     Demolition and construction equipment having a support and mounted upon the support a tip comprising a discrete base having a top side, a bottom side, a front side, and walls therebetween; a generally planar mounting surface on the top side of the base adapted to be secured to a support; a central portion with a cutting edge, whereby the cutting edge is defined at the lowermost portion of the bottom side of the base at the intersection with the front side; and a recess extending into at least one wall of the base, wherein the recess defines a recess upper side, an inner wall and a recess contour; wherein the recess upper side has generally planar sections and extends in a direction parallel to the mounting surface and; wherein the recess further includes a keyway within the generally planar sections of the upper side; and an insert having a top side, a bottom side, a front side, and walls therebetween; a cutting edge defined at the lowermost portion of the bottom side of the insert at the intersection with the front side; and a profile which generally conforms to the recess contour, wherein the top side has generally planar sections and further includes a key protruding from and adjacent to the generally planar sections of the top side; and wherein an insert is secured within each recess such that the top side of the insert mates with the upper side of the recess and wherein the keyway is engaged by the key to provide an interlocking arrangement between the base and the insert. 
     A method of securing inserts within a tip for demolition and construction equipment having a discrete base with a top side, a bottom side and walls therebetween, a mounting surface on the top side of the base adapted to be secured to a support, a central portion with a cutting edge, whereby the cutting edge is defined at the lowermost portion of the bottom side of the base, and a recess extending into two opposing walls of the base, wherein each recess defines a recess upper wall, an inner side and a recess contour, wherein the base recess includes a keyway adjacent to the generally planar sections of the upper side and wherein the insert top side has generally planar sections and includes a key adjacent to and protruding from the generally planar sections of the top side, wherein the method comprises the steps of providing a common bore through the insert and the walls of the base at each recess; positioning an insert within each recess; inserting a fastener therethrough; and securing the fastener against each insert within the recess. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is prior art and is a side view illustrating a metal shear incorporated into a universal body for a construction tool system; 
         FIG. 2  is prior art and is a plan view of the shear in  FIG. 1 ; 
         FIG. 3  is prior art and is a front view of a blade tip; 
         FIG. 4  is prior art and is a side view of the blade tip shown in  FIG. 3 ; 
         FIG. 5  is prior art and is a perspective view of a blade tip having replaceable inserts secured within a base utilizing a projection/socket arrangement; 
         FIG. 6  is a side view of a blade tip in accordance with the subject invention; 
         FIG. 7  is an exploded perspective view of the blade tip in accordance with the subject invention; 
         FIG. 8  is a different exploded perspective view of the blade tip in  FIG. 7 ; 
         FIG. 9  is a side view of the base; 
         FIG. 9A  is an enlarged portion of  FIG. 9 ; 
         FIG. 10  is a side view of an insert that fits within the base; 
         FIG. 11  is an exploded perspective view illustrating the manner in which the insert fits within the base; 
         FIG. 12  is an exploded section view showing the manner by which the tips are secured to the base; 
         FIG. 13  is a schematic illustrating the manner by which the extended tip of the base operates on a work piece; 
         FIG. 14  is a side view of an alternate embodiment of the base; 
         FIG. 15  is a side view of an alternate embodiment of the insert; 
         FIG. 16  is an exploded section view similar to  FIG. 12  showing different features associated with the bolt and base; and 
         FIG. 17  is an exploded section view similar to  FIG. 12  but showing other different features associated with the bolt and one insert. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     For purposes of the description hereinafter, the terms “upper”, “lower”, “right”, “left”, “vertical”, “horizontal”, “top”, “bottom” and derivatives thereof shall relate to the invention as it is oriented in the drawing figures. However, it is to be understood that the invention may assume various alternative variations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the invention. Hence, specific dimensions and other physical characteristics related to the embodiments disclosed herein are not to be considered as limiting. 
       FIG. 6  illustrates a blade tip  200  secured to a support  205  such as the upper jaw  13  of the jaw assembly  22  used in an industrial shear. It should be appreciated that although this tip  200  will be discussed in the context of an industrial shear associated with the demolition equipment, such a blade tip  200 , can be implemented on any type of equipment that shears, cuts, cracks, crunches, or processes any type of material by motion of the blade tip. 
     The blade tip  200  may be utilized, for example, as a shear, tip, claw, tooth, crusher tooth, and any and all piercing/punching devices that currently exist or that may be developed. This tip has immediate application for products which add shears, claws, scrapples, crushers, crackers, rail breakers, multi-blade cutters, tree shears, ripper teeth, grinding teeth, shearing teeth, and any mechanism that can utilize a disposable cutting part which is subjected to wear. 
     Directing attention to  FIGS. 7-10 , the tip  200  is comprised of a discrete base  214  having a top side  216 , a bottom side  218 , a front side  219 , and walls  220 ,  222  therebetween. The base  214  has a generally planar mounting surface  224  on the top side  216 , wherein the mounting surface  224  is adapted to be secured to the support  205  ( FIG. 6 ). The base  214  has a central portion  226  with a cutting edge  228 , whereby the cutting edge  228  is defined at the lower most portion  230  of the bottom side  218  of the base  214  at the intersection with the front side  219 . A recess  232 ,  233  extends into each wall  220 ,  222  of the base  214 . The recess  232  defines a recess upper side  234 , a recess inner wall  236 , and generally planar sections  235   a ,  235   b  defining a recess contour  238  ( FIG. 9 ). While the recess  232  extending into wall  220  will be explained in detail, it should be appreciated that the recess  233  extending into wall  222  is identical and is a mirror image. 
     Directing attention to insert  250 , the insert  250  has a top side  252 , a bottom side  254 , a front side  255 , and walls  256 ,  258  therebetween. A cutting edge  260  is defined at the lower most portion  262  of the bottom side  254  of the insert  250 . 
     As illustrated in  FIGS. 9 and 9A , the recess upper side  234  has generally planar sections  235   a ,  235   b  and extends in a direction parallel to the mounting surface  224 . The recess  232  further includes a keyway  240  adjacent to the generally planar sections  235   a ,  235   b  of the upper side  234 . 
     Directing attention to  FIGS. 10 and 11 , the profile  264  of the insert  250  generally conforms to the contour  238  of the recess  232  of the base  214 . The top side  252  of the insert  250  has generally planar sections  253   a ,  253   b  and further includes a key  265  protruding from the generally planar sections  253   a ,  253   b  of the top side  252 . As a result, the insert  250  may be secured within the recess  232  such that the top side  252  of the insert mates with the upper side  234  of the recess  232 , wherein the keyway  240  of the base  214  is engaged by the key  265  of the insert  250  to provide an interlocking arrangement between the base  214  and the insert  250 . The profile  264  of the insert  250  generally conforms to the contour  238  of the recess  232 . The recess contour  238  is triangular and the profile  264  of the tip  250  corresponds to that shape. The insert  250  is secured within the recess  232 . 
     Directing attention to  FIG. 12 , when the insert  250  is secured within the recess  232 , the cutting edge  228  of the base  214  is situated below the cutting edge  260  of the insert  250 . This is also true for insert  285  within the recess  282 . The bolt  272  has a head  274  and a threaded end  276 . The bolt  272  extends through the insert  250  and through the common bore  270  and the insert  285 . The bolt head  274  fits within the countersink  261  of the insert  250  and the threaded portion  276  of the bolt  272  engages a threaded portion of the bore  287  within the insert  285 .  FIG. 16  shows an arrangement similar to  FIG. 12 , however, the bore  370  extending through the base  314  is threaded and the bolt  372  is shortened to be threaded directly into the bore  370  of the base  314  to secure insert  360 , while another bolt (not shown) may be used in a similar fashion to secure an insert similar to insert  360  to the opposite side of the base  314 . Additionally, rather than having a threaded base  287  for insert  284  as shown in  FIG. 12  the insert  484  as illustrated in  FIG. 17 , may have a countersunk base  486  to receive a threaded nut  487  such that the bolt  472  is engaged with the threaded nut  487  to secure the inserts  472 ,  484 . 
     Directing attention to  FIGS. 9 and 9A , the keyway  240  is comprised of a radiussed segment  242  within the base  232 . The segment  242  has, at an end  244  closest to the front side  219 , a terminal  245  defined by a radial line R 1  forming a front angle F of between 1-90 degrees with the generally planar mounting sections  235   a ,  235   b  and has at an end  246  furthest from the front side  219  a terminal  247  defined by a radial line R 2  forming a back angle B of between 180-270 degrees with the generally planar mounting sections  235   a ,  235   b . In one preferred embodiment, the front angle F is between 40 and 50 degrees and the back angle B is between 190 and 210 degrees and preferably the front angle F is 42 degrees and the back angle B is 200 degrees. 
     Redirecting attention to  FIG. 7 , the base  214  further includes a socket  266  extending into the inner wall  236  of the recess  232 . The insert  250  further includes a projection  268  extending from the wall  258 , wherein the projection  268  fits within the socket  266  to support the insert  250  within the recess  232 . As illustrated in  FIGS. 7 and 11 , the socket  266  and the projection  268  having matching shapes and are non-circular, such that when the insert  250  is mounted within the recess  232 , there is no relative rotation between the socket  266  and the projection  268 . Insert  285  also has such a projection  268 ′. 
     The socket  266  has an upper side  267  which is continuous from and has a contour identical to the adjacent recess upper side  234 . Furthermore, the projection  268  has a top side  269  which is continuous from and has a contour identical to the adjacent insert top side  252 . As further illustrated, in  FIG. 11 , the upper side  267  of the socket  266  and the upper side  234  of the recess  232  have a profile identical to that of the insert top side  252  and the projection  268  top side  269 , respectively. 
     As illustrated in  FIGS. 7 and 8 , a common bore  270  extends through the insert  250 , the base  214 , and the insert  285 . The fastener  272  passes through the common bore  270  and secures the inserts  250 ,  285  within the respective recesses  232 ,  282 . The fastener  272  made be a threaded bolt having a bolt head  274  and a threaded shaft  276 . The bore  270  may include a counterbore  273  ( FIG. 10 ) within the insert  250  to accept the bolt head  274  and, furthermore, the bore  270  within the base  214  may have threads (not shown) to accept the threaded shaft  276 . 
     While so far a single recess  232  and a single insert  250  have been discussed in detail, a second recess  278  ( FIG. 7 ) is associated with the opposite wall  222  of the base  214  and a second insert  285  is secured within the recess  278  in the same fashion as the insert  250  is secured within the recess  232 . 
     In the alternative, an insert having all of the features of insert  285  with the exception of a countersunk portion of the bore to accept the nut  286  may itself have a threaded bore to accept the threaded shaft  276  of the bolt  272 , thereby alleviating the need for the nut  286  and the corresponding countersunk portion within the insert  285  to accommodate the nut  286 . 
     Returning to  FIGS. 7 and 8 , the mounting surface  224  of the base  214  has one of a cavity  290  extending therefrom or a projection  292  extending therefrom adapted to mate with a support surface  207  having the other of the cavity  290  or projection  292  to provide additional stability to a mounted tip  200 . As illustrated in  FIGS. 7 and 8 , the profiles of the cavity  290  and the projection  292  are non-circular, such that the orientation and the alignment of the mounting surface  224  of the tip  200  relative to the mounting surface  207  of the support  205  may be made easier. 
     Directing attention to  FIG. 5 , the prior art discloses a base  100  with a cutting edge  128  and two inserts  150 ,  185  with cutting edges  160 ,  184 , respectively, whereby the cutting edges  128 ,  160 ,  184  are aligned with one another. While this arrangement provides for maximum strength since all of the cutting edges are acting in unison, there are situations in which it is desired to impart the cutting force onto a shorter length of the cutting edge, thereby improving the cutting ability of that shortened segment. 
     Directing attention to  FIGS. 7 and 12 , the front side  219  of the base  232  to the cutting edge  228  has a length L1 that is longer than the length L2 of the front side  255  of the insert  250  to the cutting edge  260  and of insert  285  to the cutting edge  284 , such that the cutting edge  228  of the base  232  protrudes beyond the cutting edges  260 ,  284  of each insert  250 ,  285 . As illustrated in  FIG. 12 , the width W of the cutting edge  228  may be shortened by including beveled edges  229  to provide a transition between the cutting edge  228  and the adjacent cutting edges  260 ,  284 . 
       FIG. 13  illustrates the manner by which the cutting edge  228  of the base  232  protrudes beyond the cutting edge  260  of insert  250  and the cutting edge  284  of insert  285 . In particular, the blade tip  200 , for example, is part of the first blade  12  in  FIG. 1  and the second blade  15  includes a guide channel  38  therebetween with opposing walls  40 ,  42 . The shortened cutting edge  228  is urged against a work piece  300  and applies a central load thereto. The concentrated central load of the cutting edge  228  is more efficient at cutting through the work piece  300  and initiates a tearing process which is then completed by the adjacent cutting edges  260 ,  284  working in conjunction with the cutting edge  228 . 
     Briefly returning to  FIGS. 9 and 10 , the top side  252  of insert  250  adjacent to the bore  270  has a convex radiussed extension  280  to provide additional material to the insert  250  in the region of the bore  270 . Furthermore, as illustrated in  FIG. 9 , the upper side  234  of the recess  232  of the base  214  has a matching concave radiussed depression  282  to accept the extension  280 . 
     What has so far been described is a keyway  240  of the base  214  and a key  265  of the insert  250  having matching arcuate edges. 
     Directing attention to  FIGS. 14 and 15 , it is also possible for the keyway  240 ′ to be comprised of a rectangular segment  305  within the base  214  having a side  307  closest to the front side  219  of the base  214  forming a front angle F of between 1-90 degrees with generally planar mounting sections  235   a ,  235   b  of the base  214  and having a side  309  farthest from the front side  219  of the base  214  forming a back angle B of between 180-270 degrees with the generally planar mounting sections  235   a ,  235   b . Preferably, the front angle F is between 60-90 degrees and the back angle B is between 240-270 degrees and even more preferably, the front angle F is 90 degrees and the back angle B is 270 degrees. The associated insert  250  has a matching rectangular key  265 ′ with generally planar mounting sections  253   a ,  253   b  with a convex radiussed extension  280  that mates with the concave radiussed depression  282  in the base  214 . 
     The subject invention is also directed to a method of securing inserts  250 ,  285  within a tip  200  for demolition and construction equipment comprising the steps of providing a common bore  270  through the insert  250  and the walls  236 ,  237  of the base  214  at each recess  232 ,  276 . Each insert  250 ,  285  is positioned within its respective recess  232 ,  276 . A fastener  272  is inserted within the common bore  270  and the fastener  272  is then secured against each insert  250 ,  285  within the respective recess  232 ,  282 . 
     It should be appreciated that under most circumstances, the only maintenance for tip  200  will be the replacement of the inserts  250 ,  284 . However, it is possible to remove the base  214  from the support  236  to replace the entire tip  200 , such that the tip  200  may be considered to be disposable. Furthermore, depending on the application for which the tip  200  may be used, the material of the base  214  and the material of the tip  200  may be different. 
     As a result, the tip  200  in accordance with the subject invention, machine down time and the associated expense may be significantly reduced because more tips may be quickly and easily replaced and, furthermore, the tips, when mounted within the base, are securely held to extend the life of the tips. 
     The invention has been described with reference to the preferred embodiments. Obvious modifications and alterations will occur to others upon reading and understanding the proceeding detail description. It is intended that the invention be construed as including all such modifications and alterations.

Technology Classification (CPC): 4