Rear Deploying Broadhead

Abstract

The present invention is a rear-deploying broadhead with a body that is attachable to an arrow shaft. It has a body attachable to an arrow shaft by any manner known in the art, and has an outer housing, an inner spine, and at least two blades pivotally attached to the inner spine, with the inner spine having a first end with a plunger end, and a second end which is pointed. The broadhead has an external coating of thermoplastic or similar material having an impact value allowing said coating to retain until the broadhead impacts a target, at which point the blades deploy through the external coating.

I claim: 
     
         1 . A rear-deploying broadhead comprising a body attachable to an arrow shaft, said body comprising an outer housing, an inner spine, and at least two blades pivotally attached to said inner spine,
 wherein said inner spine has a first end with a plunger end, and a second end with a pointed end,   wherein the outer housing comprises a first closed end that terminates proximal to a structure for attaching the body to an arrow shaft and a second end which is open, wherein said outer housing comprises two lateral sides with are substantially open adjacent the second end of the outer housing,   wherein said outer housing further comprises a front side and a rear side which both terminate at the second end of the outer housing with a pointed end,   wherein said inner spine is shorter than the outer housing and is substantially disposed in the center of said outer housing, with said plunger end seated snuggly but movably inside the outer housing adjacent the first end of said outer housing, wherein, in a nondeployed state, the second end of the inner spine extends slightly beyond the furthest extent of the second end of the outer housing, and   wherein said broadhead further comprises an external coating of a heatshrink plastic having an impact value allowing said coating to retain until the broadhead impacts a target, at which point the blades deploy through the external coating.   
     
     
         2 . The broadhead of  claim 1 , wherein said at least two blades pivotally attached to the inner spine are in a retracted position in a nondeployed state. 
     
     
         3 . The broadhead of  claim 2 , wherein the at least two blades are held in a retracted position in a nondeployed state by friction, and are configured to deploy through the substantially open lateral sides of the outer housing upon movement of the inner spine toward the first end of the outer housing. 
     
     
         4 . The broadhead of  claim 1 , wherein said two blades are each pivotally attached to said inner spine at two points on the inner spine. 
     
     
         5 . The broadhead of  claim 4 , wherein said two blades are each pivotally attached to said inner spine at least at a point approximately midway between the two ends of said inner spine. 
     
     
         6 . The broadhead of  claim 5 , wherein said two blades are each pivotally attached to said inner spine at least at a point proximal to the level of the termination of the second end of the outer housing. 
     
     
         7 . The broadhead of  claim 5 , wherein said two blades are pivotally attached at two points on the inner spine, with a first attachment approximately midway between the two ends of said inner spine and a second attachment proximal to the level of the termination of the second end of the outer housing. 
     
     
         8 . The broadhead of  claim 1 , wherein said heatshrink plastic coating is 37 gauge or thinner. 
     
     
         9 . The broadhead of  claim 1 , wherein said heatshrink plastic coating is comprised of at least one of a thermoplastic material selected from the group consisting of polyolefin, fluoropolymer, polyvinylchloride, neoprene, and silicone elastomer.