Possible Clues:

• Goes with baked clay slab for revolutionary entrance feature
• Rotating mechanism for fans
• Point of access -- until rest shifted
• Means of entry in ground lest I should emerge?
• 'Vessels' in title needing changing -- it's a pivotal passage
• Mechanical entry gate
• Underground item frequently swiped
• Crowd-controlling gate, at entrance to sports-ground say
• Ballpark-entrance device
• Pivoting gate, to football grounds say