Damped spacer articles and disk drive assemblies containing damped spacer articles

Abstract

The present invention relates to a vibration damped spacer articles having good force (torque and/or pressure and/or stress) retention, and disk drives having a damped spacer article and a rotatable storage article inserted therein.

It is claimed:  
     
         1 . A disk drive assembly comprising a spacer article wherein said spacer article comprises: 
 a laminate, wherein the laminate comprises: 
 (a) two substrate layers;  
 (b) a layer of vibration damping material comprising a viscoelastic material, wherein the storage modulus of each substrate layer is greater than that of the viscoelastic material in the vibration damping material layer;  
 wherein the layer of vibration damping material is laminated between the two substrate layers within the laminate;  
 wherein the substrate is substantially ring shaped;  
 wherein the laminate has a configuration in partial cross-section which is U-shaped; and wherein the spacer article has a through hole therein.  
   
     
     
         2 . The spacer article of  claim 1  wherein the spacer article has a force retention of at least about 92 percent of an initial compression force of 1.4×10  6  Pascals applied to the spacer article for about 0.2 to about 2 seconds at about 25° C. at about 15 minutes after the application of the initial compression force.  
     
     
         3 . A disk drive assembly comprising: 
 (a) a disk drive, the disk drive having a spindle;    (b) a rotatable storage article positioned such that the spindle extends through a through hole in the rotatable storage article;    (c) a damped spacer article, wherein the damped spacer article is positioned such that the spindle extends through the through hole in the spacer article, wherein the spacer article is positioned adjacent to and in contact with the rotatable storage article;    wherein the spacer article has a flatness such that it does not cause any warpage, kinking, high spots, crimps, dents, bends, or deflections of the rotatable storage article; and    (d) a means for securing the rotatable storage article and spacer article onto the spindle.    
     
     
         4 . A disk drive assembly comprising a spacer article wherein said spacer article comprises: 
 (a) a substrate, the substrate having a through hole, the substrate having a sideways U-shape in partial cross-section, the substrate comprising an upper base, a lower base, and a side joining the upper base and the lower base, the substrate having an internal cavity; and    (b) vibration damping material comprising a viscoelastic material, wherein the storage modulus of each substrate is greater than that of the viscoelastic material in the vibration damping material,    wherein the vibration damping material is positioned within the cavity of the substrate such that it is contact with at least both the upper base and the lower base of the substrate,    wherein the substrate is substantially ring shaped; and wherein the spacer article has a through hole therein.    
     
     
         5 . The spacer article of  claim 4  wherein the vibration damping material in the cavity is compressed and/or elongated such that its height within the cavity is reduced by about 0.05 to about 75% of its initial uncompressed and/or unelongated height.  
     
     
         6 . The spacer article of  claim 4  wherein the spacer article has a force retention of at least about 92 percent of an initial compression force of 1.4×10 6  Pascals applied to the spacer article for about 0.2 to about 2 seconds at about 25° C. at about 15 minutes after the application of the initial compression force.  
     
     
         7 . The spacer article of  claim 4  wherein the substrate is substantially ring shaped and the vibration damping material is substantially ring-shaped.  
     
     
         8 . A disk drive assembly comprising a spacer article wherein said spacer article comprises: 
 a laminate having a through hole, the laminate comprising: 
 (i) an upper substrate layer and a lower substrate layer;  
 (ii) a layer of vibration damping material comprising a viscoelastic material positioned between said upper and lower substrate layers;  
 wherein the storage modulus of each substrate layer is greater than that of the viscoelastic material in the vibration damping material layer;  
 wherein at least one deformation area is present in said spacer wherein a deformation area is an area of the spacer article wherein at least one substrate layer is plastically deformed such that the upper and lower substrate layers are touching or positioned closer to each other than in an area of the spacer article in which none of the substrates are plastically deformed; and  
 wherein, in the layer of vibration damping material, within at least a 0.5% area of the deformation area, the vibration damping material is non-existant or, if present has a mass that is 90% or less than the average mass of the vibration damping material layer of an equal area in an area of the spacer article which is not in a deformation area  
   wherein the substrate is substantially ring shaped;    wherein the laminate has a configuration in partial cross-section which is U-shaped; and wherein the spacer article has a through hole therein.    
     
     
         9 . The disk drive assembly of  claim 8  wherein said spacer article comprises: 
 a laminate, the laminate having a through hole therein, wherein the laminate comprises: 
 (i) an upper substrate layer and a lower substrate layer;  
 (ii) a layer of vibration damping material comprising a viscoelastic material positioned between said upper and lower substrate layers;  
 wherein the storage modulus of each substrate layer is greater than that of the viscoelastic material in the vibration damping material layer;  
 wherein the substrate is substantially ring shaped; and  
 wherein the spacer article is welded such that the upper substrate is welded to the lower substrate.