Crankshaft isolating pulley

1. An isolating pulley comprising:

a hub ( 1 ) comprising an inertia carrier ( 16 ), the inertia carrier having an inner surface ( 168 );

a spring carrier ( 14 ) journalled to the hub, the spring carrier having a releasable driving engagement with the inertia carrier;

a pulley ( 3 ) journalled to the hub;

a spring ( 4 ) drivingly engaged between the spring carrier and the pulley;

a clutch spring ( 5 ) having a frictional engagement with the inner surface; and

which frictional engagement is partially releasable upon a temporary, pressing contact of the pulley upon the clutch spring.

2. The isolating pulley as in claim 1 further comprising an inertia member engaged with the inertia carrier, a damping member disposed between the inertia carrier and the inertia member.

3. The isolating pulley as in claim 1 , wherein the hub further comprises a toothed surface.

4. The isolating pulley as in claim 1 , wherein the spring is driven in an unwinding direction.

5. The isolating pulley as in claim 1 , wherein the pulley comprises an adjustable release member to adjust an engagement torque with the clutch spring.

6. An isolating pulley comprising:

a hub comprising an inertia carrier, the inertia carrier having an inner surface;

a spring carrier journalled to the hub, the spring carrier having a releasable driving engagement with the inertia carrier;

a pulley journalled to the hub, the pulley comprising an adjustable release member to adjust an engagement torque with the clutch spring;

a spring drivingly engaged between the spring carrier and the pulley;

a clutch spring having a frictional engagement with the inner surface; and

which frictional engagement is partially releasable upon a temporary, pressing contact of the pulley upon the clutch spring.

7. The isolating pulley as in claim 6 further comprising an inertia member engaged with the inertia carrier, a damping member disposed between the inertia carrier and the inertia member.

8. The isolating pulley as in claim 7 , wherein the hub further comprises a toothed surface.

9. The isolating pulley as in claim 8 , wherein the spring is driven in an unwinding direction.

10. An isolating pulley comprising:

a hub comprising an inertia carrier, the inertia carrier having an inner surface;

an inertia member engaged with the inertia carrier, a damping member disposed between the inertia carrier and the inertia member;

a spring carrier journalled to the hub, the spring carrier having a releasable driving engagement with the hub;

a pulley journalled to the hub, the pulley comprising an adjustable release member to adjust an engagement torque with an end of the clutch spring;

a spring drivingly engaged between the spring carrier and the pulley;

a clutch spring having a frictional engagement with the inner surface; and

which frictional engagement is partially releasable upon a temporary, pressing contact of the pulley upon the clutch spring in a winding direction.

11. The isolating pulley as in claim 10 , wherein:

the spring carrier comprises a projecting member engagable with a cooperating member projecting from the hub.

12. The isolating pulley as in claim 11 , wherein:

the cooperating member projecting from the hub comprises a resilient material.

13. The isolating pulley as in claim 12 , wherein the pulley comprises an adjustable release member to adjust an engagement torque with the clutch spring.

14. The isolating pulley as in claim 13 , wherein the spring is driven in an unwinding direction.

15. The isolating pulley as in claim 14 , wherein the hub comprises a toothed surface.

16. The isolating pulley as in claim 15 , wherein the pulley comprises a multi-ribbed surface.