US Patent 7357453 Chair with armrests

This invention teaches a chair comprising a seat; a backrest; a first armrest; a second armrest; a seat support structure; means for supporting the lower back of a seated person; a first slider; a second slider; a first slideway having a plurality of cavities; and a second slideway having a plurality of cavities, wherein the first slider and the second slider are disposed at two opposite ends of the means for supporting the lower back of a seated person; the first slideway is cooperating with the first slider and is connected to the first armrest; and the second slideway is cooperating with the second slider and is connected to the second armrest.