Patent ID: 7543315

Claim:
A disk-clamping device for clamping a disk disposed within a disk drive that includes a spindle motor, the disk being formed with a central through hole, the spindle motor being coupled to the disk-clamping device in order to rotate the disk in cooperation with the disk-clamping device, the disk-clamping device comprising: a mounting seat including a first clamping plate and a protrusive element projecting upwardly from a center of said first clamping plate to permit sleeving of the through hole around said protrusive element for seating the disk onto said first clamping plate; a clamp member disposed above said mounting seat, and including a second clamping plate having a bottom surface and a central recess that extends inwardly from said bottom surface and that is defined by a recess-confining wall having an upper wall surface confining an upper side of said central recess, said second clamping plate further defining an imaginary line intersecting said central recess into a first half and a second half symmetric to said first half; and a first projection structure disposed on said upper wall surface in said first half of said central recess in said second clamping plate; whereby, during clamping operation of said mounting seat and said clamp member in order to sandwich the disk between the first and second clamping plates, extension of said protrusive element into said central recess in said clamp member results in collision of said protrusive element against said first projection structure prior to said protrusive element against said upper wall surface of said central recess, thereby lowering a noise generated due to collision between said upper wall surface of said central recess against said protrusive element.