Isolator decoupler

1. An isolator decoupler comprising:

a pulley ( 3 );

a shaft ( 11 );

a bushing ( 2 ) slidingly engaged with the pulley and Slidingly engaged with the shaft;

the pulley journalled to the shaft by a bearing ( 8 );

a one-way clutch ( 7 ) fixed to the shaft and engaged with the bushing whereby the bushing rotates in unison with the one-way clutch;

a torsion spring ( 4 ) engaged between the pulley and the one-way clutch to resiliently couple the pulley to the shaft; and

the pulley non-resiliently directly coupleable to the shaft in a temporary predetermined loaded condition.

2. The isolator decoupler as in claim 1 , wherein the torsion spring is torsionally loaded in an unwinding direction.

3. The isolator decoupler as in claim 1 further comprising:

a one-way clutch carrier engaged operationally between the bushing and the one-way clutch, the one-way clutch carrier having a first tab;

a spring retaining member connect to the pulley and engaging the torsion spring, the spring retaining member having a second tab;

the first tab and second tab cooperatively engagable whereby a rotational range of movement of the spring retaining member with respect to the one-way clutch carrier is limited between the first position and the second position wherein the pulley is capable of being temporarily directly coupled with the shaft in a maximum loading condition.

4. The isolator decoupler as in claim 1 , wherein the temporary predetermined condition is a spring overload condition.