PROTECTIVE COVERING FOR WEARABLE DEVICES
Embodiments of the present application relate generally to personal electronics, portable electronics, wearable electronics, and more specifically to a structure and method for a protective covering for a wearable device. Interior and exterior structures of the wearable device are configured to be flexed into a configuration and to retain the configuration after the flexing. Interior structure may include a first flexible substrate having a first relaxation structure and a second flexible substrate having a second relaxation structure. Components or other structures may be connected with the first and/or second flexible substrates. The first and second relaxation structures may be positioned relative to each other to define a flexure point. At least one flexible and electrically non-conductive cover, that may undergo shirking, may conformally cover at least a portion of the interior structure. A flexible overmolding may be formed over the cover and may comprise the exterior structure.
1 . A wearable structure, comprising:
a flexible substrate (FS) including a first relaxation structure, the FS configured to retain its shape after being flexed into a configuration;
a flexible dielectric (FD) including circuitry, electrically conductive traces, a bonding pad, and a second relaxation structure, a portion of the circuitry is interconnected using the electrically conductive traces and another portion is interconnected using a wire that straddles the second relaxation structure and is electrically connected with the bonding pad;
an encapsulation structure positioned adjacent to the second relaxation structure and covering the bonding pad and a portion of the wire;
a strain relief positioned adjacent to the second relaxation structure and in contact with a portion of the wire; and
a flexible and electrically non-conductive cover including one or more sections that partially or completely conformally covers the FS, the FD, the encapsulation structure, and the strain relief.
2 . The structure of claim 1 , wherein the first relaxation structure is integrally formed in the FS.
3 . (canceled)
4 . The structure of claim 1 , wherein a first end of the wire is electrically connected with the bonding pad and a second end of the wire is electrically connected with an electrical component.
5 . (canceled)
6 . The structure of claim 1 , wherein a first end of the wire is electrically connected with the bonding pad and second end of the wire is electrically connected with another bonding pad.
7 . The structure of claim 6 , wherein the bonding pad and the another bonding pad are positioned on opposite sides of the second relaxation structure.
8 . The structure of claim 1 , wherein the second relaxation structure and the first relaxation structure are disposed adjacent to each other.
9 . The structure of claim 1 , wherein the second relaxation structure and the first relaxation structure are disposed adjacent to each other and positioned at a flexure point in a wearable device.
10 . The structure of claim 1 , wherein portions of the one or more sections conformally cover portions of a selected one or more of the FS, the FD, the encapsulation structure, or the strain relief.
11 . The structure of claim 1 , wherein the wire has a profile over a portion of its span that approximates a profile of the second relaxation structure.
12 . The structure of claim 1 , wherein at least one of the one or more sections is transparent.
13 . The structure of claim 1 , wherein the second relaxation structure is integrally formed in the FD.
14 . The structure of claim 1 , wherein a contour of the second relaxation structure approximately matches another contour of a loop mandrel.
15 . The structure of claim 1 , wherein the FD comprises a component selected from the group consisting of flexible printed circuitry (FPC) and flat flexible cable (FFC).
16 . The structure of claim 1 , wherein the FS comprises a component selected from the group consisting of a metal, a flat substrate, a flat metal substrate, a spring, and a flat spring.
17 . The structure of claim 1 , wherein the one or more sections are made from a material that when heated, shrinks in a dimension by a ratio of at least 1.5:1.
18 . The structure of claim 17 , wherein the material after shrinking, is mechanically stable over a temperature range from about 100° C. to about 300° C.
19 . The structure of claim 1 and further comprising:
a flexible overmolding in contact with and covering the one or more sections.
20 . The structure of claim 1 , wherein the FS comprises at least two separate sections and the first relaxation structure is connected with a portion of one section and a portion of another section.
21 . The structure of claim 1 , wherein the second relaxation structure comprises a service loop.
22 . A method for fabricating a wearable device, comprising:
providing a first flexible substrate (FFS) configured to retain its shape after being flexed into a configuration, the FFS including a first relaxation structure;
providing a second flexible substrate (SFS) including a second relaxation structure;
connecting the FFS and the SFS with each other with the first relaxation structure and the second relaxation structure positioned in a predetermined alignment relative to each other;
positioning the FFS, the SFS and one or more components coupled with the FFS, the SFS or both in an interior of a flexible and electrically non-conductive cover (FC);
shrinking a dimension of the FC until the FC conformally covers at least a portion of the FFS, the SFS and the one or more components; and
forming a flexible overmolding over an exterior of the FC.