The closing device consisting of a sleeve that seals onto the neck of a bottle and that comprises an internal channel which opens, via a new orifice in a sliding-contact surface with associated slopes and slideways acting as guide means to a shut-off plate for closing the new orifice which is moved translationally by a knob, which sliding-contact surface may be planar or in the form of a sector of a cylinder of revolution or in the form of a portion of a sphere.

The invention relates to a manual grinder for mounting on the neck (C) of a receptacle for foodstuffs in the form of grains, the grinder being characterized in that it comprises firstly a fixed ring (1) provided with a flange (11) for supporting it on the receptacle, which flange is downwardly extended by an inner sleeve (12) that is engaged in said neck (C) and that presents a toothed inner side wall (12a), and secondly a cap (2) rotatably mounted on said neck (C) covering said ring (1) and including a peripheral skirt (21) radially connected to a central bushing (22) having a toothed outer side wall (22a) that is engaged coaxially in said sleeve (12), so as to define between them a peripheral grinding zone (10).