The rigid chain propulsion is the best available system to operate a retractable grandstand in public buildings. The movement for opening or closing the structure is fully guided and will never use the traction of the floor it is build on. 

Independent

The chain system is developed in a way that it can pull and push objects in a very effective and efficient manner. Unlike friction (drum) engines, which needs surface resistance, the rigid chain system moves the platforms from its own chassis. The system operates completely independent and regardless of the floor, the tribune will be retracted and extended perfectly parallel.

High stability

Beside opening and closing the grandstand this system takes care of the stability of the full metal structure. In open position the chain and system are a fixed connection from back to front and from left to right. It makes your audience walk on a fixed grandstand! 

Full automatic seating rows

A very pleasant feature of our system is the fact that we can use the power of the propulsion system to have the VIP chairs set up straight when opening the grandstand. With retraction the chairs will be folded down in a controlled automated way. No more physical labour and damaged chairs.