Vehicle seat tract assembly with secondary system

A vehicle seat track assembly comprising:

• an elongated fixed track structure constructed and arranged to be fixed with respect to a vehicle floor;
• a movable track structure cooperable with said fixed track structure and constructed and arranged to support a portion of a seat thereon;
• a plurality of rolling elements engaged between said track structures constructed and arranged to rollingly support said movable track structure on said fixed track structure to enable said movable track structure to be moved in opposite directions through a range of adjusting movements with respect to said fixed track structure;
• an adjusting mechanism operatively associated with said track structures and constructed and ganged permit said movable track structure to be moved through the adjusting movements, said adjusting mechanism including a locking and releasing device constructed and arranged to be moved between (1) a locking position preventing said adjusting movements from being affected and (2) a releasing position wherein said locking and releasing device is operable to release said adjusting mechanism to permit said adjusting movements,
• a lock and release system operatively associated with said track structures and including a locking structure disposed in a released position permitting said adjusting movements during normal operating conditions and movable to a locked position preventing said adjusting movements from being affected, said lock and release system including a shock responsive structure constructed and arranged to move said locking structure from the released position to the locked position thereof in response to a crash condition which occurs while said locking and releasing device is in said releasing position, and wherein
• the shock responsive structure comprises a bracket fixed to said movable track structure and a movable member mounted for rotational movement with respect to said bracket, said movable member, being operable to move said locking structure between the released and locked positions thereof and said movable member defining an interior cavity filled with fluid,
• said shock responsive structure including a shock responsive member received in said cavity and being coupled to said movable member in such a manner that during a crash condition, said movable member will rotate together with said shock responsive member moving said locking structure to the locked position thereof and during normal operating conditions, said shock responsive member will rotate without causing rotation of said movable member maintaining said locking structure in the released position thereof.