US Patent 7775597 Folding seats

A folding seat has a support structure, a backrest and a seat base. The seat base is pivotally mounted on the support structure for pivoting between a seating position with the seat base extending generally horizontally and the backrest generally vertically, a stored position with the base and backrest both extending generally vertically, and a table position with base and backrest both extending generally horizontally. A first over-centre spring biases the seat base towards its generally horizontal position or its generally vertical position depending on the location of the base. Also, a second over-centre spring biases the backrest towards its generally vertical position or its generally horizontal position depending on the location of the backrest.