cousoir

CONT: [The sewing frame] consists of a flat baseboard, two uprights threaded on both ends, a crossbar and two supporting wooden nuts. Tapes, cords, or bands are stretched from the slotted baseboard, where they are secured by keys, to the crossbar, where they are attached to loops (laycords), or, in German models, to hooks.
OBS: The sewing frame was certainly in use in Northern Europe by the 12th century, and probably as early as the 11th, because in all likelihood the need for some type of frame became apparent as soon as flexible sewing was introduced.