Smart Material Actuated Fasteners

Abstract

A smart material actuated fastener is provided. In another aspect, a fastener includes a shape memory material and a non-shape memory material with the shape memory material being a minority of the total fastener materials. A further aspect provides a fastener having workpiece-engaging surfaces made of an inactive and non-shape memory material.

1 . A fastener comprising:
 a shape memory material;   a non-shape memory material, the shape memory material being a minority of the total fastener materials;   an inner head made of the non-shape memory material;   an outer base made of the non-shape memory material; and   legs spanning between the inner head and the outer base in a curved and outwardly radiating manner, the legs being made of the shape memory material;   the legs causing rotation when the shape memory material is activated.   
     
     
         2 . The fastener of  claim 1 , further comprising a first rigid wall having a curved surface and at least a second rigid wall having a curved surface facing that of the first wall, the rigid walls being made of the non-shape memory material, the first rigid wall being an inside edge of the base and the second rigid wall being an outside edge of the head. 
     
     
         3 . The fastener of  claim 2 , wherein the shape memory material moves the walls relative to each other when the shape memory material is actuated. 
     
     
         4 . The fastener of  claim 1 , further comprising an internally threaded segment of the head operably receiving an externally threaded shaft therein, and the head operably rotating when the shape memory material is activated. 
     
     
         5 . The fastener of  claim 1 , wherein the shape memory material is metallic and the non-shape memory material is polymeric. 
     
     
         6 . The fastener of  claim 1 , wherein the shape memory material is polymeric and the non-shape memory material is polymeric. 
     
     
         7 . The fastener of  claim 1 , wherein the shape memory material rotates the head which includes projecting surface formations within a hollow inner cavity thereof. 
     
     
         8 . The fastener of  claim 1 , wherein the head is internally threaded. 
     
     
         9 . The fastener of  claim 1 , wherein the head is hollow. 
     
     
         10 . The fastener of  claim 1 , wherein the head includes internal barbs. 
     
     
         11 . The fastener of  claim 1 , wherein the head includes a circular periphery and the base includes a circular internal surface, the head and base are coaxially aligned, and the head is located within a hole in the base. 
     
     
         12 . The fastener of  claim 1 , wherein the head includes a hollow segment longitudinally elongated above an upper flat plane of the base and a longitudinally elongated groove is in an outer surface of the head. 
     
     
         13 . The fastener of  claim 1 , further comprising a bolt, stud, axle or shaft located within the head. 
     
     
         14 . The fastener of  claim 1 , further comprising an elongated projection, attached to an automotive vehicle component, being coupled to the head. 
     
     
         15 . The fastener of  claim 1 , further comprising an elongated projection, attached to a computer housing or electrical component, being coupled to the head. 
     
     
         16 . A fastener comprising:
 a head made of the non-shape memory material;   a base made of the non-shape memory material;   legs spanning between the head and the base in an outwardly radiating manner, the legs including the shape memory material; and   the head being configured to receive an elongated shaft therein.   
     
     
         17 . The fastener of  claim 16 , wherein the head is internally threaded. 
     
     
         18 . The fastener of  claim 16 , wherein the head is hollow. 
     
     
         19 . The fastener of  claim 16 , wherein the head includes internal barbs. 
     
     
         20 . The fastener of  claim 16 , wherein the head includes a circular periphery and the base includes a circular internal surface, the head and base are coaxially aligned, and the head is located within a hole in the base. 
     
     
         21 . The fastener of  claim 16 , wherein the head includes a hollow segment longitudinally elongated above an upper flat plane of the base. 
     
     
         22 . The fastener of  claim 16 , wherein the shaft is externally threaded. 
     
     
         23 . The fastener of  claim 16 , wherein the shaft is an axle. 
     
     
         24 . The fastener of  claim 16 , wherein the base is an attachment bracket. 
     
     
         25 . The fastener of  claim 16 , wherein there are more than three of the legs, and the legs are curved. 
     
     
         26 . The fastener of  claim 16 , further comprising a circular rim coupling outboard ends of the legs to the base. 
     
     
         27 . The fastener of  claim 16 , wherein the legs rotate the head relative to the base when activated. 
     
     
         28 . A fastener comprising:
 a nut made of a non-shape memory material, the nut including an internally projecting surface formation;   a base made of a non-shape memory material, the base including a hole; and   spaced apart legs coupled to the nut, the nut being located within the hole of the base;   the legs including shape memory material such that activation of the legs moves the nut relative to the base.   
     
     
         29 . The fastener of  claim 28 , further comprising an elongated shaft located within the nut, the legs being elongated between their ends, and the legs outwardly radiating in a curved manner between the nut and the base. 
     
     
         30 . The fastener of  claim 29 , wherein the shaft is externally threaded. 
     
     
         31 . The fastener of  claim 29 , wherein the shaft is an axle. 
     
     
         32 . The fastener of  claim 28 , wherein the formation of the nut defines an internal thread. 
     
     
         33 . The fastener of  claim 28 , wherein the nut is hollow. 
     
     
         34 . The fastener of  claim 28 , wherein the formation of the nut defines internal barbs. 
     
     
         35 . The fastener of  claim 28 , wherein the nut includes a circular periphery and the base includes a circular internal surface, the nut and base are coaxially aligned, and at least one of the nut and base are polymeric. 
     
     
         36 . The fastener of  claim 28 , wherein the nut includes a circular periphery and the base includes a circular internal surface, the nut and base are coaxially aligned, and at least one of the nut and base are metallic. 
     
     
         37 . The fastener of  claim 28 , wherein the nut includes a hollow segment longitudinally elongated above an upper flat plane of the base. 
     
     
         38 . The fastener of  claim 28 , further comprising an externally threaded bolt or stud operably secured within the nut. 
     
     
         39 . The fastener of  claim 28 , wherein the base is an attachment bracket. 
     
     
         40 . The fastener of  claim 28 , wherein there are more than three of the legs which outwardly span between the nut and the base. 
     
     
         41 . The fastener of  claim 28 , further comprising a circular rim coupling outboard ends of the legs to the base. 
     
     
         42 . The fastener of  claim 28 , further comprising an elongated projection, attached to an automotive vehicle component, being coupled to the nut. 
     
     
         43 . The fastener of  claim 28 , further comprising an elongated projection, attached to a computer housing or electrical component, being coupled to the nut.