Pressure sensor unit for detecting whether a seat is occupied

The unit has bars (15) arranged at two long sides of a support plate (1). The long sides face each other and extend along a direction of connecting lines of centers or focus points of sensor elements (4). Distance between edges of each sensor element and the support plate is half the extended distance of the sensor element in a transverse direction when viewing from top of the support plate and three times the maximum extended distance of the sensor element in the transverse direction when viewing orthogonal to the bars.