Translatable Expandable Collets, Systems and Methods with Anti-Rotation Feature

Abstract

Methods for fastening at least a first object and a second object together from only one side using a collet body having a first end, a second end and an anti-rotation feature include inserting the first end through aligned first and second object holes, which define a common axis, axially translating the anti-rotation feature through at least a portion of the first object hole, engaging the anti-rotation feature with a mechanical ground, which may be one or both objects or a sleeve insert, whereby free rotation of the collet body is substantially counteracted by the rotational, but not axial, interference between the anti-rotation feature and the mechanical ground, and axially retracting the collet body before, during or after radially outwardly displacing at least two displaceable fingers at the first end of the collet body.

1 . A method for fastening at least a first object and a second object together with a collet body, wherein each object defines a hole and the holes have generally equal diameters, and
 wherein the collet body comprises
 a first end defining a generally circular opening; 
 a first wall portion adjacent to the first end, the first wall portion having an interior surface, an exterior surface, a progressing radial profile and defining at least two secondary slots extending longitudinally from the first end to thereby create at least two fingers having a distal end at the first end; 
 a second end defining a generally circular opening; 
 a second wall portion adjacent to the second end, the second wall portion having an interior surface, and an exterior surface; 
 an annular protrusion extending from the first wall portion having a leading face and a trailing face; and 
 anti-rotation means for engaging with a mechanical ground; 
   the method comprising:
 a) inserting the collet body first end through aligned first and second object holes, which define a common axis; 
 b) axially translating the collet body anti-rotation means through at least a portion of the first object hole; 
 c) engaging the collet body anti-rotation means with the mechanical ground, whereby free rotation of the collet body is substantially counteracted by the rotational, but not axial, interference between the anti-rotation means the mechanical ground; and 
   d) axially retracting the collet body before, while or after presenting a radially outward force at the interior surface of the first wall portion.   
     
     
         2 . The method of  claim 1  wherein the mechanical ground is selected from the group consisting of the first object and the second object. 
     
     
         3 . The method of  claim 1  wherein the mechanical ground is a sleeve insert fixedly associated with one of the first object or the second object. 
     
     
         4 . The method of  claim 1  wherein an interior surface of the collet body is threaded and a cylindrical stud threaded complementary thereto presents the radially outward force at the interior surface of the first wall portion when rotationally introduced into the collet body. 
     
     
         5 . The method of  claim 4  wherein the interior surface of the second wall portion comprises the threaded portion. 
     
     
         6 . The method of  claim 4  wherein a portion of the threaded stud contacts the first object and the annular protrusion of the collet body contacts the second object when the two objects are fastened together. 
     
     
         7 . The method of  claim 1  wherein the axial retraction of the collet body results from the rotational engagement of a threaded cylindrical stud with complementary threads formed on an interior surface of the collet body. 
     
     
         8 . The method of  claim 1  wherein the collet body anti-rotation means extends from the outer surface of the second wall portion. 
     
     
         9 . The method of  claim 1  wherein the collet body anti-rotation means depends towards the inner surface of the second wall portion. 
     
     
         10 . The method of  claim 1  further comprising engaging a portion of the collet body with one of the first object, the second object or a sleeve insert to prevent axial translation of the collet body second end beyond the second object hole. 
     
     
         11 . The method of  claim 10  wherein the collet body anti-rotation means engages with one of the first object, the second object or a sleeve insert to prevent axial translation of the collet body second end beyond the second object hole. 
     
     
         12 . The method of  claim 10  wherein a portion of the collet body engages with a radially inwardly extending lip in the hole of one of the first object, the second object or a sleeve insert to prevent axial translation of the collet body second end beyond the second object hole. 
     
     
         13 . The method of  claim 12  wherein the collet body anti-rotation means engages with a radially inwardly extending lip in the hole of one of the first object, the second object or a sleeve insert to prevent axial translation of the collet body second end beyond the second object hole. 
     
     
         14 . The method of  claim 1  wherein the mechanical ground is one of the first object, the second object, or a sleeve rigidly linked to the second object, and whereby the axial retraction of the collet body results from the rotational engagement of a threaded cylindrical stud with complementary threads formed on an interior surface of the collet body and whereby the radially outward force at the interior surface of the first wall portion results from the presentation of the stud thereat. 
     
     
         15 . The method of  claim 14  further comprising engaging a portion of the collet body with one of the first object, the second object or a sleeve insert to prevent axial translation of the collet body second end beyond the second object hole. 
     
     
         16 . The method of  claim 15  wherein a portion of the collet body engages with a radially inwardly extending lip in the hole of one of the first object, the second object or a sleeve insert to prevent axial translation of the collet body second end beyond the second object hole. 
     
     
         17 . The method of  claim 16  wherein the collet body anti-rotation means engages with a radially inwardly extending lip in the hole of one of the first object, the second object or a sleeve insert to prevent axial translation of the collet body second end beyond the second object hole.