Rotatable support elements for stents

Abstract

Various embodiments of methods and devices for coating stents are described herein. The method includes applying a coating composition to the stent; rotating the stent with a rotatable element supporting at least a portion of the stent; and applying at least one pulse to the rotatable element during the stent coating process.

What is claimed is: 
     
         1 . A method of coating a stent comprising: applying a coating composition to the stent; rotating the stent with a rotatable element supporting at least a portion of the stent; and applying at least one pulse to the rotatable element during the stent coating process. 
     
     
         2 . The method of  claim 1 , wherein the at least one pulse causes the rotatable element to rotate relative to the stent. 
     
     
         3 . The method of  claim 1 , wherein the at least one pulse causes a shift in an area of contact between the rotatable element and the stent. 
     
     
         4 . The method of  claim 1 , wherein the at least one pulse has a duration between about 0.0001 second and about 1 second. 
     
     
         5 . The method of  claim 1 , wherein a rotation rate within a duration of the at least one pulse changes from a first non-zero rate to a second non-zero rate different from the first non-zero rate. 
     
     
         6 . The method of  claim 5 , wherein the rotation rate within the duration of the at least one pulse changes from the second non-zero rate to a third non-zero rate, and the second non-zero rate is greater than the first and third non-zero rates. 
     
     
         7 . The method of  claim 6 , wherein the first and third non-zero rates are different from one another. 
     
     
         8 . The method of  claim 6 , wherein the first and third non-zero rates are the same as one another. 
     
     
         9 . The method of  claim 5 , wherein the rotation rate within the duration of the at least one pulse changes from the second non-zero rate to a third non-zero rate, and the second non-zero rate is less than the first and third non-zero rates. 
     
     
         10 . The method of  claim 1 , wherein the applying the at least one pulse comprises applying a plurality of pulses during rotating of the stent, the plurality of pulses spaced apart at equal time intervals. 
     
     
         11 . The method of  claim 10 , wherein each of the plurality of pulses occur at a frequency no greater than about 5 Hz. 
     
     
         12 . The method of  claim 1 , wherein the applying of the at least one pulse comprises applying a plurality of pulses during rotating of the stent, the plurality of pulses spaced apart at unequal time intervals. 
     
     
         13 . The method of  claim 1 , further comprising: translating the stent in an axial direction of the stent with the rotatable element during the stent coating process. 
     
     
         14 . The method of  claim 1 , wherein the applying the stent coating composition comprises spraying the stent coating composition onto the stent. 
     
     
         15 . The method of  claim 1 , wherein the at least one pulse causes sliding or slipping of the stent with respect to the rotatable element such that coating defects are prevented or minimized. 
     
     
         16 . The method of  claim 1 , wherein the at least one pulse comprises a monotonic increase in a rotation rate of the rotatable support element. 
     
     
         17 . The method of  claim 1 , further comprising: controlling a maximum rate of the at least one pulse. 
     
     
         18 . The method of  claim 1 , further comprising: controlling a degree of acceleration of the at least one pulse. 
     
     
         19 . The method of  claim 1 , further comprising: controlling a duration of the at least one pulse. 
     
     
         20 . The method of  claim 1 , wherein the stent is fit loosely on the rotatable element such that the stent shifts relative to the rotatable element during the rotation of the stent. 
     
     
         21 . The method of  claim 1 , wherein during the rotating the stent, the stent shifts relative to the rotatable element, and further wherein the at least one pulse changes a rotational rate of the rotatable element to cause the stent to further shift with respect to the rotatable element.