Replaceable demolition shear piercing tip

Abstract

A heavy-duty demolition shear with a replaceable shearing tip has a lower jaw and an upper jaw piviotally connected to the lower jaw. The upper jaw has primary and secondary shear blades. A replaceable shearing tip is mounted to the upper jaw. The replaceable shearing tip has two L-shaped sections which engage the upper jaw between them. The replaceable shearing tip engages the upper jaw on at least three seats. The replaceable shearing tip is connected to the upper jaw by socket-head cap-screws.

What is claimed: 
     
       1. A heavy-duty demolition shear with a replaceable shearing tip, the apparatus having a lower jaw and an upper jaw pivotally connected to the lower jaw, the upper jaw having a shearing blade, comprising:
 (a) a tip mounting portion on the upper jaw, the shearing blade having a cutting edge on a lower, planar shearing surface and a tip mounting surface, the tip mounting surface meeting the cutting edge an acute angle to the cutting edge;   (b) a replaceable shearing tip mountable to the tip mounting portion, wherein the replaceable shearing tip further comprises two sections encompassing the tip mounting portion there-between, wherein the two sections are L-shaped and having a first arm and a second arm, the first arm and the second arm each comprising a continuous planar surface;   (c) wherein the first arm of the L meets the cutting edge of the shearing blade at an oblique angle; wherein the upper jaw further comprises at least three seats for engaging the replaceable shearing tip, wherein one of the at least three seats is the tip mounting surface of the shear blade, and wherein the replaceable shearing tip abuts firmly against the tip mounting surface without a gap; and   (d) wherein the continuous planar surface of the second arm of the L forms a dihedral angle with the plane of the shearing surface of the shearing blade.   
     
     
       2. A heavy-duty demolition shear with a replaceable shearing tip, the apparatus having a lower jaw and an upper jaw pivotally connected to the lower jaw by a pivot means, the upper jaw having a shearing blade, the shearing blade having a cutting edge and a shearing surface, comprising:
 (a) a replaceable shearing tip;   (b) a replaceable shearing tip mounting portion on the upper jaw, wherein the replaceable shearing tip further comprises two sections encompassing the replaceable shearing tip mounting portion there-between, wherein the two sections are L-shaped;   (c) the shearing blade having a replaceable shearing tip mounting surface, the replaceable shearing tip mounting surface meeting the cutting edge at an acute angle to the cutting edge;   (d) wherein the replaceable shearing tip abuts firmly against the replaceable shearing tip mounting surface without a gap;   (e) the replaceable shearing tip meets the cutting edge of the shearing blade at an oblique angle; and   (f) wherein each of the L-shaped sections further comprises a first arm and a second arm, each of the first arm and the second arm comprising a continuous planar surface, the first arm abutting against the replaceable shearing tip mounting surface of the shearing blade without a gap, the shearing surface of the shearing blade forming a single continuous plane parallel to the axis of the pivot means, the single continuous planar surface of the second arm meeting the single continuous plane of the shearing surface of the shearing blade at a dihedral angle.   
     
     
       3. A heavy-duty demolition shear with a replaceable shearing tip, the apparatus having a lower jaw and an upper jaw pivotally connected to the lower jaw, the upper jaw having a shearing blade, the shearing blade having a first side, a second side, and a lower, planar shearing surface between the first side and the second side of the heavy duty demolition shear comprising:
 (a) a tip mounting portion on the upper jaw, the shearing blade having a cutting edge and a tip mounting surface, the tip mounting surface meeting the cutting edge at an acute angle to the cutting edge;   (b) a replaceable shearing tip mountable to the tip mounting portion, wherein the replaceable shearing tip further comprises two sections encompassing the tip mounting portion there-between, wherein the two sections are L-shaped and having a first arm and a second arm;   (c) wherein the first arm of the L-shape meets the cutting edge of the shearing blade at an oblique angle; wherein the upper jaw further comprises at least three seats for engaging the replaceable shearing tip, wherein one of the at least three seats is the tip mounting surface of the shear blade, and wherein the replaceable shearing tip abuts firmly against the tip mounting surface without a gap; and   (d) wherein the second arm of the L forms a single continuous plane, said single continuous plane forming a dihedral angle with the lower, planar shearing surface.   
     
     
       4. The heavy-duty demolition shear of  claim 3 , wherein the acute angle and oblique angle are supplementary. 
     
     
       5. A heavy-duty demolition shear with a replaceable shearing tip, the apparatus having a lower jaw and an upper jaw pivotally connected to the lower jaw, the upper jaw having a shearing blade, the shearing blade having a cutting edge on a lower, planar shearing surface, comprising:
 (a) a replaceable shearing tip;   (b) a replaceable shearing tip mounting portion on the upper jaw, wherein the replaceable shearing tip further comprises two sections encompassing the replaceable shearing tip mounting portion there-between, wherein the two sections are L-shaped;   (c) the shearing blade having a replaceable shearing tip mounting surface, the replaceable shearing tip mounting surface meeting the cutting edge at an acute angle to the cutting edge;   (d) wherein the replaceable shearing tip abuts firmly against the replaceable shearing tip mounting surface without a gap;   (e) the replaceable shearing tip meets the cutting edge of the shearing blade at an oblique angle; and   (f) wherein each of the L-shaped sections further comprises a first arm and a second arm, the first arm abutting against the replaceable shearing tip mounting surface of the shearing blade without a gap, the second arm of the L lying in a single continuous plane, the plane of the second arm meeting the plane of the shearing surface at a dihedral angle.   
     
     
       6. The heavy demolition shear of  claim 5 , wherein the acute angle and the oblique angle are supplementary. 
     
     
       7. A tip adapted to mount to a nose of an upper jaw of a demolition shear, the nose having a first laterally recessed mounting surface on a first side defining a first nose ledge surface and a second laterally recessed mounting surface on a second side defining a second nose ledge surface, wherein a lateral distance between the first and second lateral recessed mounting surfaces define a nose tip width, the nose tip width having a bottom end, the upper jaw of the demolition shear further having a shear blade, the shear blade having a forward edge, the tip comprising:
 (a) a first tip body having an inside face, an outside face, a top edge, a rear edge and a bottom flange extending laterally inward from said inside face such that said first tip body defines an L-shape in cross-section, said bottom flange having a continuous planar bottom surface;   wherein, when said first tip body is mounted to the nose of the upper jaw of the demolition shear,
 (i) said bottom flange extends at least partially across the bottom end of the nose tip width from the first side; 
 (ii) said inside face of said first tip body is disposed adjacent the first laterally recessed mounting surface; 
 (iii) said top edge of said first tip body engages the first nose ledge; and 
 (iv) a portion of said rear edge engages the forward edge of the shear blade at an oblique angle; 
   (b) a second tip body having an inside face, an outside face, a top edge, a rear edge and a bottom flange extending laterally inward from said inside face such that said second tip body defines an L-shape in cross-section, said bottom flange having a continuous planar bottom surface;   wherein, when said second tip body is mounted to the nose of the upper jaw of the demolition shear,
 (i) said bottom flange extends at least partially across the bottom end of the nose tip width from the second side; 
 (ii) said inside face of said second tip body is disposed adjacent the second laterally recessed mounting surface; and 
 (iii) said top edge of said second tip body engages the second nose ledge.  
   
     
     
       8. The tip of claim 7, whereby;
 when said first tip body is mounted to the first side of the nose, said continuous planar bottom surface of said bottom flange of said first tip body is at an angle α1 between a range of about −10 degrees to about +35 degrees from a lower edge of the shear blade.    
     
     
       9. The tip of claim 7, whereby;
 when said first tip body is mounted to the first side of the nose, the top edge of said first tip body is at an angle α2 between a range of about −20 degrees to about +25 degrees from a top edge of the shear blade.    
     
     
       10. The tip of claim 7, whereby;
 when said first tip body is mounted to the first side of the nose, a front surface of said first tip body is at an angle α3 between a range of about 55 degrees to about 75 degrees from a lower edge of the shear blade.    
     
     
       11. The tip of claim 7 wherein;
 said continuous planar bottom surface of said bottom flange of said first tip body is at an angle α4 between a range of about −15 degrees to about +15 degrees from a top side of said bottom flange of said first tip body; and   said continuous planar bottom surface of said bottom flange of said second tip body is at an angle α4 between a range of about −15 degrees to about +15 degrees from a top side of said bottom flange of said second tip body.