Device for detecting the liquid level in the washing bath of a washing machine

A device (1) for providing a signal indicating the instantaneous level of a liquid in a container, comprising

• a hollow body (2) wherein there is defined an inner region (14, 15) which is divided into first and second chambers (14, 15) which are sealingly separated from one another by a resilient diaphragm (6), the first chamber (14) having an inlet opening (2c) for pneumatic communication with the region which in the container is above said liquid, the second chamber (15) communicating with the atmosphere;
• a winding or coil (8) mounted in a fixed position in the body (2), on the side opposite the first chamber (14) with respect to the diaphragm (6);
• a core ferromagnetic (11) coupled to the diaphragm (6) and movable with respect to the winding (8) such that in the operation the inductance of the winding (8) varies as a function of the position of said core;
• and
• first resilient means (12) tending to move the core (11) towards the diaphragm (6) and second resilient means (16) tending to oppose the action of the first resilient means (12);
• said second resilient means (16) being disposed in said second chamber (15),
• wherein said second resilient means comprise a spiral spring (16) whose peripheral portion is mounted in the body (2) by a coupling which is essentially of the bayonet type,
• wherein the winding (8) is carried by a spool member (7) mounted in the body (2) and having an hollow lower portion (7b) in which there is mounted said spiral spring (16), and
• wherein the spiral spring (16) has first guiding cut-outs (18) alternated with second coupling cut-outs (19), and said hollow portion (7b) of the spool member (7) has a plurality of guiding protuberances (20) adapted to engage with said first cut-outs (18) of the spring (16) to allow the introduction of the spring in the spool member (7) up to a position in which the spring (16) is capable of being rotated such that the coupling cut-outs (19) are aligned and capable of being coupled with corresponding retaining formations (21) of said lower portion (7b) of the spool member (7).