Snap ring with debris-reducing cross-sectional profile
A snap ring for applications requiring cleanliness has a novel blunted cross-sectional profile that reduces debris generation during installation of the snap ring. The snap ring is suitable for applications where a reduction in debris generation is desirable, such as to retain an actuator pivot bearing in information storage devices like magnetic hard disk drives.
1 . A snap ring, comprising:
a ring with an interior contour that extends about an opening and has a first interior edge bordering a first face of the snap ring and a second interior edge bordering a second face of the snap ring, the first interior edge having a cross-sectional profile that includes die roll, and the second interior edge having a cross-sectional profile that is blunted.
2 . The snap ring of claim 1 , wherein said blunted cross-sectional profile is a rounded profile at least at a point within a region of the interior contour where contact with another solid object occurs during installation of the snap ring.
3 . The snap ring of claim 1 , wherein said blunted cross-sectional profile is a beveled profile at least at a point within a region of the interior contour where contact with another solid object occurs during installation of the snap ring.
4 . The snap ring of claim 2 , wherein said rounded profile is characterized by a radius of curvature that is chosen to be in the design range of 40% to 85% of the thickness of the snap ring.
5 . The snap ring of claim 3 , wherein said beveled profile is characterized by a bevel angle that is chosen to be in the design range of 10 to 40 degrees from the vertical axis.
6 . The snap ring of claim 3 , wherein said beveled profile is characterized by a bevel depth that is chosen to be in the design range of 60% to 85% of the thickness of the snap ring.
7 . An actuator arm assembly for an information storage device, comprising:
an actuator; and
an actuator pivot bearing; and
a snap ring retaining the actuator pivot bearing relative to the actuator, the snap ring having an interior contour that extends about an opening and has a first interior edge bordering a first face of the snap ring and a second interior edge bordering a second face of the snap ring, the first interior edge having a cross-sectional profile that includes die roll, and the second interior edge having a cross-sectional profile that is blunted.
8 . The actuator arm assembly of claim 7 , wherein said blunted cross-sectional profile is a rounded profile at least at a point within a region of the interior contour where contact with another solid object occurs during installation of the snap ring.
9 . The actuator arm assembly of claim 7 , wherein said blunted cross-sectional profile is a beveled profile at least at a point within a region of the interior contour where contact with another solid object occurs during installation of the snap ring.
10 . The actuator arm assembly of claim 8 , wherein said rounded profile is characterized by a radius of curvature that is chosen to be in the design range of 40% to 85% of the thickness of the snap ring.
11 . The actuator arm assembly of claim 9 , wherein said beveled profile is characterized by a bevel angle that is chosen to be in the design range of 10 to 40 degrees from the vertical axis.
12 . The actuator arm assembly of claim 9 , wherein said beveled profile is characterized by a bevel depth that is chosen to be in the design range of 60% to 85% of the thickness of the snap ring.
13 . A method to manufacture a snap ring, comprising:
stamping an interior contour that extends about an opening,
forming a blunted cross-sectional profile on an edge opposite an edge having die roll caused by said stamping.
14 . The method of claim 13 wherein said forming a blunted cross-sectional profile comprises coining a rounded cross-sectional profile.
15 . The method of claim 13 wherein said forming a blunted cross-sectional profile comprises coining a beveled cross-sectional profile.
16 . A method for assembling an actuator arm assembly in an information storage device, comprising:
fabricating a snap ring, wherein said fabricating includes stamping an interior contour that extends about an opening, and forming a blunted cross-sectional profile on an edge opposite an edge having die roll caused by said stamping; and
installing the snap ring onto an actuator pivot bearing.
17 . The method of claim 16 wherein said installing includes contact between the snap ring and another solid object in at least one contacting region along the interior contour.
18 . The method of claim 17 wherein said solid object includes an installation cone having a cylindrical cross-section.
19 . The method of claim 17 wherein said forming a blunted cross-sectional profile comprises coining a rounded cross-sectional profile at least in said contacting region.
20 . The method of claim 17 wherein said forming a blunted cross-sectional profile comprises coining a beveled cross-sectional profile at least in said contacting region.