| 摘要 |
1. An electrical switch device actuated by pressure, and comprising a housing (2), a cover (6) mounted on the housing and thereby securing between them the edge portion of a diaphragm (10) subjected to the pressure, at least one snap-action (20, 20b, 20c) arranged in the housing, of which switch the contact carrier is in the form of a leaf spring (34) held in the housing and extending substantially parallel to the diaphragm (10), there being a tongue (38) cut out of the surface of the leaf spring (34), the root or origin of the tongue (38) being located at the securing point of the leaf spring (34) and the free end of the tongue (38) being braced through a spring (44) to the end of the leaf spring (34) carrying the switch contact (32), whereby this tongue (38) can be moved in the course of a switching action by the diaphragm (10) through a compression member (18) in a direction perpendicular to the diaphragm, such that the tongue acts through the spring (44) to bring the switch contact (32) at the end of the leaf spring (34) into contact with either one or the other of two fixed switch contacts (50, 52) ; wherein at least one of the fixed contacts (52) is adjustable and wherein as a further provision for the adjustement of the switching point of each snap-action switch (20, 20b, 20c) there is arranged between each tongue (38) and the housing (13) an additional spring (62) with one end braced against a bolt (64) which is screwed into the housing (13), characterized in that, in the direction of actuation of the leaf spring (34) of at least one of the first-mentioned snap switches (20, 20b, 20c), and between its tongue (38) and the housing (13), there is situated a safety snap-switch (70) which is operated directly and mechanically by the tongue (38) but which is insulated from it, said safety snap-switch having two detents (82, 84) of which at least one is in the form of a contact (84). |
