Tactile switch unit

A tactile switch unit comprising:

• a case;
• a link mechanism having first and second links disposed in said case, rotatably supported intermediately of their ends to sad case and having their inner ends rotatably coupled to each other;
• a slider located above said link mechanism and vertically movable housed in said case, and having a flat top and a plurality of legs for rotatably supporting outer ends of said first and second links;
• a membrane sheet disposed on said flat top of said slider and having formed therein a plurality of membrane switches;
• a knob fixedly integrated with said slider and having apertures in its top panel fitted in a top opening of said case;
• a surface sheet having formed thereon a plurality of press areas and disposed on the top panel of said knob with said press areas aligned with said apertures;
• a pusher having a plurality of pusher elements disposed on said membrane sheet in opposing relation to the back of said press areas, respectively, each of said pusher elements being designed so that upon depression of said press area corresponding thereto, said each pusher element is pressed to urge said membrane switch corresponding thereto;
• a tactile push-button switch disposed in said case and turned ON/OFF by pivotal movement of said link mechanism;
• a bottom plate attached to said case on the bottom side thereof;
• and
• a light source mounted on the inside surface of said bottom plate, for illuminating a symbol provided in said each press area;
• wherein said membrane sheet except a conductor portion and said pusher are formed of a light transmitting material.