A SAFETY ARRANGEMENT FOR A HEIGHT-ADJUSTABLE SEAT STRUCTURE AND A VEHICLE SEAT IN A TRUCK, LORRY OR BUS USING SUCH SAFETY ARRANGEMENT

A safety arrangement for a height-adjustable seat structure is provided. The seat structure (100) comprises a first set of legs (101A) comprising a first leg (105A) pivotably connected to a second leg (108A), and a first pair of guide rails (102A) comprising an upper and a lower guide rail (103A, 104A). The first leg comprises one end portion (106A) being pivotably hinged to the upper guide rail and one end portion (107A) being linearly movable (107A) along the lower guide rail. The second leg (108A) comprises one end portion (109A) pivotably hinged to the lower guide rail (104A) and one end portion (110A) being linearly movable along the upper guide rail (103A). The seat structure further comprises a stop member (202) and a seat actuator (200) comprising a piston (201). The seat actuator is configured, upon an activation signal, to move the piston from a retracted position to an extended position in which a free end of the piston is configured to exert a force to an impact surface (204) of the stop member, whereby the piston forces the seat structure towards a lowered position. The piston forms an impact angle α of 25-65 degrees as seen between the piston and a horizontal plane. Also, a vehicle seat in a truck, lorry or bus provided with such safety arrangement is disclosed.