Abstract: Working vessel for an electric household appliance for culinary preparation including a removable collar (4) and a casing (3) comprising a bottom end equipped with an opening (30A) surrounded by a sleeve (30) on which said collar (4) can be coupled by turning, said collar (4) comprising a tool holder plate (43) designed to project through said opening (30A), wherein the working vessel includes locking means (6) movable between a locking position, in which the collar (4) and the casing (3) cannot be uncoupled, and an unlocking position in which they can be uncoupled, characterized in that the locking means (6) occupy the locking position when the working vessel is held right side up and the unlocking position when the working vessel is held upside down.