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Convex Contoured Profile for Crash Stop Posts of Hard Disk Drives for Greater Performance Characteristics Disclosure Number: IPCOM000131034D
Publication Date: 2005-Nov-04
Document File: 2 page(s) / 30K

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The Prior Art Database


Crash stop posts are normally cylindrical in shape for ease of manufacturability and reduction in cost. However, complex shaped profiles of the crash stop post are advantageous to minimize physical effects that may decrease the performance of a hard disk drive, i.e. stiction and timing problems. A novel design was prepared for a crash stop post that minimizes high speed impacts by virtue of its complex shaped profile.

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  Convex Contoured Profile for Crash Stop Posts of Hard Disk Drives for Greater Performance Characteristics

   This invention allows a stepwise or smooth polynomial shaped contour to be applied to a post to minimize the contact area between the post and the actuator tab. For materials such as soft plastics which are made of high elastomeric polymeric materials are greatly desirable since they minimize the elastic collision by absorbing much of the energy of the collision. The coefficient of restitution of these plastics are less than 50% which help in decreasing the bounce-off condition associated with high speed collisions of the actuator. However, because the high degree of elasticity and softness associated with such posts, the detrimental effect, that is encountered is stiction effects between the post and the actuator tab. The harder the actuator tab presses into the post and the more time it spends pressed against it, the greater the stiction force between the post and the tab.

To overcome these difficulties, a novel design has been proposed to overcome the stiction effects of the post. In this design shown in Figure 1, the profile of a typical post is shown with a stepwise convex contour shape. The shape can be either a stepwise convex line or a smooth polynomial line which allows a large protrusion in the center of the post, tapering off towards both ends of the post. The drawing in Figure 1 shows a stepwise convex line. A smooth polynomial line can also be proposed for this design. In this manner, the actual area of contact can be as small as 25%. This will allow approximately a 25% smaller stiction force to be applied to the actuator tab.

The crash stop post can also allow for differences in materials as a function of the stepwise convex profile. Steps 1 and 7 can be made of ve...