Flex cable assembly with improved flex cable dynamic loop characteristics
View Patent ↗A flex cable assembly for use in a disc drive data storage device includes a laminated flex cable and a flex cable support. The flex cable provides electrical communication paths between a moveable head stack assembly and a disc drive printed circuit board. The flex cable support comprises a base and adjacent first and second flex support portions with respective first and second flex support surfaces. The flex cable is routed along the flex support surfaces and exerts a spring force thereagainst as the flex cable attempts to return to a nominally planar orientation. The direction of the second flex support surface establishes the orientation of a dynamic loop between the flex cable support and the head stack assembly. Preferably, a portion of the flex cable pulls away from the second flex support surface to lengthen the dynamic loop in response to movement of the head stack assembly.
1. A flex cable assembly, comprising:
a flex cable comprising a flexible member with a nominally planar orientation; and
a flex cable support comprising a base and adjacent first and second flex support portions extending from the base, wherein the first flex support portion comprises a first flex support surface extending along a first direction and providing a first retention tab, wherein the second flex support portion comprises a second flex support surface extending along a second direction and providing a second retention tab, wherein the flex cable pressingly abuts and exerts a spring force against the first and second flex support surfaces to retain the flex cable against said support surfaces, said spring force generated as the flex cable attempts to return to the nominally planar orientation, and wherein each retention tab extends through a corresponding tab aperture in the flex cable to restrict lateral movement of the flex cable.
2. The flex cable assembly of claim 1 , wherein the first and second directions intersect to form an angle of less than 180 degrees.
3. The flex cable assembly of claim 1 , wherein the first and second directions intersect to form an angle of substantially 90 degrees.
4. The flex cable assembly of claim 1 , wherein the first and second directions are substantially parallel.
5. The flex cable assembly of claim 1 , wherein a gap is formed between the first and second flex support portions to facilitate routing of the flex cable along the respective first and second flex support surfaces.
6. The flex cable assembly of claim 1 , wherein the flex cable assembly is used to conduct electrical signals to a moveable head stack assembly of a disc drive data storage device, wherein the flex cable comprises a proximal end affixed to the flex cable support and a distal end affixed to the head stack assembly.
7. The flex cable assembly of claim 1 , wherein at least a selected one of the first and second flex support surfaces is substantially planar.
8. The flex cable assembly of claim 1 , wherein at least a selected one of the first and second flex support surfaces is curvilinear.
9. A disc drive data storage device, comprising:
a rotatable disc having a data storage surface;
a head stack assembly which controllably moves a data transducing head adjacent the data storage surface; and
a flex cable assembly comprising:
a flex cable comprising a flexible member with at least one embedded electrical conductor used to transmit electrical signals to the head stack assembly, the flex cable having a nominally planar orientation, a proximal end and a distal end, said distal end affixed to the head stack assembly; and
a flex cable support comprising a base and adjacent first and second flex support portions extending from the base, the first flex support portion comprising a first flex support surface extending along a first direction, the second flex support portion comprising a second flex support surface extending along a second direction, and wherein the proximal end of the flex cable pressingly abuts and exerts a spring force against the first and second flex support surfaces to retain the flex cable against said support surfaces, said spring force generated as the flex cable attempts to return to the nominally planar orientation, and further wherein each of the first and second flex support portions further comprises a retention tab for extension through a corresponding tab aperture in the flex cable to restrict lateral movement of the flex cable.
10. The disc drive data storage device of claim 9 , wherein the flex cable further comprises a dynamic loop between the proximal and distal ends to provide strain relief for the flex cable as the head stack assembly moves the head across the data storage surface, and wherein an end of the dynamic loop adjacent the flex cable support substantially extends in the second direction of the second flex support surface.
11. The disc drive data storage device of claim 10 , wherein the dynamic loop has a nominal length along the length of the flex cable when the head is located at a first position with respect to the data storage surface, and wherein a portion of the flex cable is pulled away from the second flex support surface as the head is moved to a second position with respect to the data storage surface so that the dynamic loop achieves a second length longer than the nominal length.
12. The disc drive data storage device of claim 9 , wherein at least a selected one of the first and second flex support surfaces is substantially planar.
13. The disc drive data storage device of claim 9 , wherein at least a selected one of the first and second flex support surfaces is curvilinear.
14. The disc drive data storage device of claim 9 , further comprising a rigid base deck, wherein the base of the flex cable support is affixed to the base deck.
15. The disc drive data storage device of claim 9 , wherein the disc drive data storage device further comprises a printed circuit board affixed to an exterior surface of a base deck, and wherein the flex cable facilitates electrical communication between the head stack assembly and the printed circuit board.
16. A disc drive data storage device, comprising:
a rotatable disc having a data storage surface;
a head stack assembly which controllably moves a data transducing head adjacent the data storage surface; and
a flex cable assembly comprising:
a flex cable comprising a laminated, flexible, ribbon-like member with at least one embedded electrical conductor used to transmit electrical signals to the head stack assembly, the flex cable having a nominally planar orientation, a proximal end, a distal end, and a dynamic loop between said proximal and distal ends, wherein the distal end is affixed to the head stack assembly and wherein the dynamic loop has a nominal length when the head is located at a first position adjacent the data storage surface; and
first means for supporting the proximal end of the flex cable and for facilitating extension of the length of the dynamic loop to a second length greater than the nominal length when the head is located at a second position adjacent the data storage surface.
17. The disc drive data storage device of claim 16 , wherein the first means comprises a flex cable support comprising a base and adjacent first and second flex support portions extending from the base, the first flex support portion comprising a first flex support surface extending along a first direction, the second flex support portion comprising a second flex support surface extending along a different, second direction, and wherein the proximal end of the flex cable pressingly abuts and exerts a spring force against the first and second flex support surfaces to retain the flex cable against said support surfaces, said spring force generated as the flex cable attempts to return to the nominally planar orientation, and further wherein each the first and second flex support portions further comprises a retention tab for extending through a corresponding tab aperture in the flex cable to restrict lateral movement of the flex cable relative to each respective first and second flex support surface.