Portable external flexible cable and package using same

• US 5,468,159 A
• Filed: 08/10/1994
• Issued: 11/21/1995
• Est. Priority Date: 04/07/1993
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Brodsky, William L., Herard, James D.
• Primary Examiner(s): NGUYEN, KHIEM M
• Application Number:
  US08/288,179
• Time in Patent Office: 468 Days
• Field of Search: 439/34, 439/501, 439/502, 439/503, 439/492, 439/498, 439/499, 174/117 F, 174/117 FF, 191/12.2 A, 191/12.4, 29/842, 29/848, 29/841
• US Class Current: 439/501
• CPC Class Codes: H01B 7/0846 Parallel wires, fixed upon a support layer
• CPC Class Codes: H01B 7/0869 comprising one or more armouring, tensile- or compression-resistant elements
• CPC Class Codes: H01R 13/72 Means for accommodating flexible lead within the holder
• CPC Class Codes: H02G 11/02 using take-up reel or drum
• CPC Class Codes: H05K 1/0393 Flexible materials H05K1/038 takes precedence; specific organic compositions are classified in H05K1/0313 and subgroups

Abstract

This invention provides a means of using flexible (also often referred to as simply "flex") circuit structures for external cabling in a small light package, particularly those utilized in portable computers. The external cabling is composed of a flex circuit that is strengthened by fiber strands, and a wrapped sheath of woven mesh netting. The cabling may be further encased in an overcoating for protection against abrasion and chemicals. The packaging scheme using this cable may include a storage device for the cable such that the cable is retractable.

Claims

1. A flexible cable comprising:

a flexible circuit of substantially planar elongated shape including a dielectric having at least one edge and a plurality of metal conductive lines;

a sheath of webbed netting wrapped substantially entirely around said flexible circuit for providing reinforcement of said flexible circuit;

an overcoat of material totally surrounding and encasing said sheath of webbed netting and said flexible circuit; and

at least one round strand of reinforcement fibers positioned along said edge of said dielectric of said flexible circuit and encased within said sheath of webbed netting, said strand of reinforcement fibers preventing tearing of said flexible circuit and protecting said metal conductive lines from metal fatigue, said strand not being securedly attached to said dielectric of said flexible circuit and adapted for moving independently of said dielectric during twisting, pulling or other similar motion of said flexible cable.

2. The flexible cable of claim 1 wherein said dielectric of said flexible circuit is comprised of a polyimide film or polyethylene film base.

3. The flexible cable of claim 1 wherein said strand of reinforcement fibers is aramide.

4. The flexible cable of claim 1 wherein said conductive lines are spacedly located along an upper surface of said dielectric.

5. The flexible cable of claim 1 wherein said conductive lines are located internally of said dielectric and surrounded by said dielectric.

6. The flexible cable of claim 1 further comprising a storage case for storing said cable within said case, and a retention and retraction device for said cable, said device disposed within said case.

7. The flexible cable of claim 6 wherein said retention and retraction device comprises a spool for reeling said flexible cable, a retainer rod means for attaching said flexible cable to said spool for positioning said flexible cable such that said flexible cable is coiled around said spool when said spool is rotated in a first direction and said flexible cable is released from said coiled position when said spool is rotated in a second direction, a coil spring disposed between an inner wall of said case and said spool for biasing said spool, a ratchet wheel disposed within said ease, said ratchet wheel concentric with said spool, a release button positioned in said first opening of said ease, and an actuation lever integral with said button and disposed such that the lever extends toward said ratchet wheel, said lever having a length such that depression of said button causes said lever to release said ratchet wheel such that said coil spring forces said spool to rotate and retract said cable.

8. A portable external flexible cable system comprising:

(a) a flexible circuitry cable having a first end and a second end, said cable further including,

an essentially planar elongated segment of flexible circuit material including a dielectric having at least one edge and a plurality of metal conductive lines;

a sheath of webbed netting wrapped substantially entirely around said flexible circuit material for providing reinforcement of said flexible circuit material;

an overcoat of material totally surrounding and encasing said sheath of webbed netting and said flexible circuit material;

at least one round strand of reinforcement fibers positioned along said edge of said flexible circuit material and encased within said sheath of webbed netting, said strand of reinforcement fibers preventing tearing of said flexible circuit and protecting said metal conductive lines from metal fatigue, said strand not being securedly attached to said dielectric of said flexible circuit and adapted for moving independently of said dielectric during twisting, pulling or other similar motion of said flexible cable;

(b) a storage case having at least one opening on an exterior face;

(c) a retention and retraction device for said flexible circuitry cable disposed within said case, said retention and retraction device further including,

a spool for reeling said flexible cable;

a retainer rod disposed in rotational communication with said spool for positioning said flexible circuitry cable such that said flexible circuitry cable is coiled around said spool when said spool is rotated in a first direction and said flexible circuitry cable is released from said coiled position when said spool is rotated in a second direction;

a coil spring disposed between an inner wall of said case and said spool for biasing said spool;

a ratchet wheel disposed within said case, said ratchet wheel concentric with said spool;

a release button positioned in said first opening of said case;

an actuation lever integral with said button and disposed such that the lever extends toward said ratchet wheel, said lever having a length such that depression of said button causes said lever to release said ratchet wheel such that said coil spring forces said spool to rotate and retract said cable;

(d) said flexible circuitry cable extending through said second opening of said storage case and terminating at said first end and said second end of said cable;

(e) a first connector attached to said flexible circuitry cable at said first end; and

(f) a second connector attached to said flexible circuitry cable at said second end.

9. A method of making a flexible cable, said method comprising:

providing a flexible circuit of substantially planar elongated shape and including a dielectric having at least one edge and a plurality of metal conductive lines;

positioning at least one round strand of reinforcement fibers along said 6 edge of said dielectric of said flexible circuit for preventing tearing of said flexible circuit and for protecting said metal conductive lines from metal fatigue, said round strand not being securedly attached to said dielectric of said flexible circuit and adapted for moving independently of said dielectric during twisting, pulling or other similar motion of said flexible cable;

wrapping a sheath of webbed netting substantially entirely around said flexible circuit and said round strand of reinforcement fibers to provide reinforcement of said flexible circuit; and

totally surrounding and encasing said sheath of webbed netting with a layer of overcoat material.

10. The method as in claim 9 wherein said layer of overcoating material is applied by dipping said sheath of webbed netting, said round strand of reinforcement fibers and said flexible circuit in said overcoat material.

11. The method as in claim 9 wherein said webbed netting is wrapped about said flexible circuit in an overlapping manner using a heat staking operation.