CONGESTION PREVENTING DEVICE FOR CAR

An apparatus for preventing congestion comprises a seat body 1, air bags 5g and 5h for energizing muscles of the legs of an occupant seated on the seat body 1, air supply/ exhaust device 6 for expanding and shrinking the air bags 5g and 5h and a control circuit 8 for controlling the air supply / exhaust apparatus 6. The control circuit 8 controls the air supply/exhaust apparatus 6 to expand and shrink the air bags 5g and 5h upon a predetermined time elapsed after sitting detection means 7A detects the sitting of the occupant.