| 摘要 |
Described herein is a knob (1) including: a hub, which can be connected so that it is angularly fixed in a seat open at the front of an electrical household appliance, with a rotatable control pin of the household appliance designed to control, according to its own angular position, at least one function of the household appliance; a grip, which is carried so that it is angularly fixed but can slide axially, against the action of elastic means, on a first end of the hub opposite to a second end thereof for connection with said pin; and means for selective axial connection of the grip to the hub designed to block the grip in a first axial position, in which the grip projects in cantilever fashion from the first end of the hub and is set, in use, at least partially on the outside of said seat, and in a second axial position, in which the grip is fitted on said hub and is, in use, retracted within said seat; between the grip and the hub there being defined a closed chamber having a variable volume that is a function of the axial position of the grip on the hub and there being provided sliding seal means for sealing said air-tight chamber, and a calibrated restriction for connecting the inside of said chamber with the external environment in such a way as to bring about a negative pressure in said chamber as a result of the movement of the grip towards the first axial position. <IMAGE> |
