Cranequin fesswise (Period)
A cranequin, or crannequin, is a portable rack-and-pinion winch, used to draw a crossbow; it was also called a “cranket”. As an artifact, it dates from c.1370 [Singer 723]; as a charge, it was used as a badge by John de Vere, 13th Earl of Oxford (d.1513) [Siddons II.2 300].
The cranequin doesn’t seem to have a default orientation in Society armory: the illustration shows a cranequin fesswise.
Sylvia Schirenhoferin bears: Vert, a bison statant argent and on a chief doubly enarched Or a cranequin fesswise sable.