Viscously damped cord retract
AssigneeEricsson Inc.
InventorDavid Till
Life of this patent
Estimating the term…
Abstract
A retractable system, apparatus, and method for dispensing, receiving, and storing flexible members are disclosed. The system, apparatus, and method are comprised of a spool, an air-damper member, and a house member. The spool is adapted to receive and store varying lengths of a flexible member. The air-damper member is concentrically disposed in the spool and defines at least two rotatable air filled chambers or channels. The house member secures the spool and the air-damper member in a concentric enclosed airy arrangement.
Claims21
A damped rotary line dispensing and retracting assembly comprising:
- a spool;
- a line of material taken up in coiled relation on said spool;
- an air-damper concentrically disposed for rotation within said spool, said air-damper having at least one air-displacing vane;
- a wind-up coil spring disposed within said spool for biasing the spool to take up said line of material;
- a housing rotatable supporting said spool and said air-damper in an air chamber so that the rotation of said spool rotates said air-damper in resistance to a volume of air enclosed by said chamber;
- and
- means for rotatably coupling said spool and said air-damper so that the air damper rotates at an increased angular velocity with respect to the rotation of the spool when the spool rotates to retract said line.
A cord retraction unit especially suitable for reducing rotational inertia using air, comprising:
- an air-damper hub having an axis of rotation and at least one vane;
- a spool taking up said cord and arranged to partially enclose said air-damper hub;
- means rotatably coupling the air damper hub and spool so that said air-damper and spool rotate about said axis of rotation and so that the air-damper hub rotates at an increased angular velocity with respect to the rotation of the spool when the spool rotates to retract the cord;
- a housing having a supporting member extending through said axis of rotation so that the rotation of said spool rotates said air-damper hub in resistance to a volume of air enclosed by said housing in an airy arrangement;
- and
- means for rotatably biasing said spool to take up said cord.
A method for extending and retracting a cord, comprising the steps of:
- providing a spool with an axially aligned central cylindrical space and a peripheral support surface;
- disposing a wind-up recoil spring in axial alignment with the spool in said cylindrical space;
- providing a cord wound on the peripheral support surface of the spool;
- rotationally biasing the spool with the cord in a fully wound-up position;
- disposing a rotatable hub in axial alignment with the spring and spool within the cylindrical space of said spool;
- providing at least one air-resisting vane extending from the hub and rotating with the hub;
- rotatably coupling the hub and spool so that the hub and vane rotate at an increased angular velocity with respect to the rotation of the spool;
- pulling and unwinding the cord from the spool against the return force of the recoil spring;
- releasing the cord so that the cord winds up on the spool under the return force of the recoil spring;
- and
- rotating said at least one vane at said increased angular velocity and thereby dampening and slowing the retracting movement of the cord as the cord winds on the spool.
Dependencies are inferred from the claim text.