US 7,538,472 B2
Programmable shims for manufacturing and assembly lines
Alan L. Browne, Grosse Pointe, Mich. (US); Charles W. Wampler, II, Birmingham, Mich. (US); Andrew C. Keefe, Santa Monica, Calif. (US); Nancy L. Johnson, Northville, Mich. (US); John A. Cafeo, Farmington, Mich. (US); Gary L. Jones, Farmington Hills, Mich. (US); William Barvosa-Carter, Ventura, Calif. (US); and Nilesh D. Mankame, Sterling Heights, Mich. (US)
Assigned to Gm Global Technology Operations, Inc., Detroit, Mich. (US)
Filed on Mar. 11, 2005, as Appl. No. 11/78,693.
Claims priority of provisional application 60/552970, filed on Mar. 12, 2004.
Prior Publication US 2005/0200067 A1, Sep. 15, 2005
Int. Cl. H01L 41/08 (2006.01)
U.S. Cl. 310—311  [310/328] 23 Claims
OG exemplary drawing
 
1. A shim for positioning a work piece comprising:
a first plate attachable to said workpiece;
a reference frame;
an actuator in operative communication with the first plate and the reference frame;
wherein the actuator is selectively actuated by a first active material and wherein the first active material is at least one of a shape memory alloy, a ferromagnetic shape memory alloy, a shape memory polymer, an electroactive polymer, a piezoelectric material, a magnetostrictive material, an electrorheological fluid, a magnetorheological fluid, a magnetorheological elastomer, or a paraffin-based material;
wherein the first plate upon actuation by the actuator is displaceable with respect to the reference frame into a set position;
wherein the first plate is held in the set position by the actuator without assistance of power;
wherein said shim is configured to position a load of about 0.5 kilograms to 10,000 kilograms;
wherein the actuator further comprises a second active material to perform the holding of the first plate in the set position without assistance of power, the second active material being different from the first active material; and
wherein the second active material is at least one of a shape memory alloy, a ferromagnetic shape memory alloy, a shape memory polymer, an electroactive polymer, a piezoelectric material, a magnetostrictive material, an electrorheological fluid, a magnetorheological fluid, a magnetorheological elastomer, or a paraffin-based material.