Ground engaging tool retention system

Abstract

A ground engaging tool retainer assembly includes three components: a pin, a washer, and a bolt. The bolt includes a threaded shank. When assembled, the threaded shank passes through a central bore in the washer and engages a matching threaded bore in the pin. The washer is trapped in a pocket between the ground engaging tool and the work machine. When the bolt and pin are attached to the washer, they are also trapped on the ground engaging tool and the work machine. When installed, the pin acts as a shear pin preventing the ground engaging tool from being removed from the work machine.

1 . A retainer assembly comprising: 
 a pin elongated in the direction of a longitudinal axis, the pin being generally cylindrical in shape with an outer, cylindrical surface, a first axial end, and a second axial end opposite the first axial end, the first axial end having a threaded bore formed therein, and the second axial end having means for connecting to a tool to apply torque to the pin;    a generally annular-shaped washer having a central bore, an axial first end, and an axial second end opposite the axial first end;    a bolt having a threaded shank and a head, the head having means for connecting to a tool to apply torque to the bolt;    wherein the diameter of the washer is greater that the diameter of the cylindrical surface of the pin and the diameter of the head of the bolt; and    wherein the threaded shank of the bolt passes through the central bore of the washer, and threads into the threaded bore of the pin.    
   
   
       2 . A retainer assembly according to  claim 1  wherein: 
 the bolt includes a first tapered portion extending between the head and the threaded shank; and    the washer includes a second tapered portion extending between the central bore and the axial second end of the washer, the taper angle of the first tapered portion being generally equal to the taper angle of the second tapered portion.    
   
   
       3 . A method of attaching a ground engaging tool to a work machine, the adapter being attached to a work machine, the method comprising; 
 positioning a washer in a pocket formed on one of the tip or the adapter;    sliding the tip over a portion of the adapter in a sliding direction so that the washer is trapped and not removable from between the tip and the adapter in the pocket;    sliding the tip further in the sliding direction over the portion of the adapter until a first bore formed in the tip aligns with a second bore formed in the adapter;    inserting a pin into the first and second bore such that the pin prevents the tip from being slid in a direction opposite the sliding direction off of the adapter; and    attaching a bolt with a shank to the pin, the shank passing through a central bore in the washer, and the shank being threaded and engaging a threaded bore in the pin.    
   
   
       4 . A retainer assembly for attaching a ground engaging tool to an adapter, the adapter having a nose portion and a bore through the nose portion, the ground engaging tool having a pocket shaped such that the nose portion of the adapter will fit into the pocket when the ground engaging tool is mounted to the adapter, the ground engaging tool further having a through bore which generally aligns with the bore of the adapter when the ground engaging tool is mounted to the adapter, the retainer assembly comprising: 
 a pin elongated in the direction of a longitudinal axis, the pin having an outer surface, a first axial end, and a second axial end opposite the first axial end, the first axial end having a threaded bore formed therein, and the second axial end having means for connecting to a tool to apply torque to the pin;    a washer having a central bore, an axial first end, and an axial second end opposite the axial first end;    a mechanical fastener having a threaded shank and a head, the head having means for connecting to a tool to apply torque to the bolt;    wherein the pin is sized to pass through the bore of the adapter and the through bore of the ground engaging tool; and    wherein the washer is sized such that it cannot pass through the bore of the adapter and the through bore of the ground engaging tool.