Patent attributes
A torsion bar configured to assist height adjustment of a seat cushion frame is housed in a hollow coupling pipe positioned between side frames. The inside of the coupling pipe has first and second engagement portions configured to engage and hold one end portion of the torsion bar in an extension direction thereof. The first engagement portion is engaged with a first engaged portion of the one end portion. The second engagement portion is engaged with a second engaged portion of the one end portion in the same position as a position of engagement between the first engagement portion and the first engaged portion in the seat width direction or in a position on the inner side from the position of engagement in the seat width direction, the second engaged portion being positioned closer to one end of a biasing member in the extension direction than the first engaged portion.