Abstract: The invention relates to a leaf switch having a scroll spring (6) which can be hooked between a switching are elongate windows which extend in the transverse direction and into which centrally projecting tongues (3a, 2a) of the switching tongue (3) and of the spring lever (2) engage. In order to avoid an unintentional unhooking of the scroll spring (6), there is a deformation projecting beyond the tongue surface at the front section of at least one of the two tongues (3a, 2a). The said deformation can be constructed as an embossed hollow projection or as laterally bent-over tongue legs.

Abstract: An electrical switch includes a switch casing having an open side; a plunger received in the switch casing and projecting through the open side; a guide defined in the switch casing for guiding the plunger to perform sliding motions in response to an external force exerted thereon; a switching mechanism accommodated in the switch casing for cooperating with the plunger to make or break an electric contact in response to a sliding displacement of the plunger; a lid closing the open side of the switch casing; a sealing arrangement for sealingly securing the lid to the switch casing; and a bell-shaped resilient bellows formed on the lid as an integral part thereof. The bellows projects outwardly from the open side and sealingly surrounds the plunger.

Abstract: An electric switch, preferably with means of illumination, is of liquid-protected design and includes parts which can largely be assembled automatically. A switch housing (2) is substantially closed in the upper region and is provided with a bottom opening (11) in the lower region. A switching pin (5) of an operating element (6) passes through a small upper opening (4) into the housing and operates a contact bridge (18). The contact bridge (18) selectively connects a middle plug terminal (12) electrically with an outer plug terminal (25). An illumination unit (30) may be integrated into corresponding recesses in the housing. All parts can be fitted in a straight line into the housing through the corresponding openings (11, 4) during automatic assembly.

Abstract: An operating structure of an electrical switch is an assembly comprising a contact arm part, a fixed contact part and an insulating part preferably sandwiched therebetween. The contact arm part and the fixed contact arm are made of electrically conducting material. The insulating part is preferably of a thermoplastic material. The contact arm part and the fixed contact part are provided each with two securing holes. To assemble the three parts, the material of the insulating part in its portions associated with the securing holes is locally brought into a plastic state and bulged out through the securing holes. Then, the bulges are flattened, clinched or the like, at the other side to form a structure which is joined by quasi-rivets of plastic. The manufacture of this structure takes place in a timed sequence with suitable stamping and forming tools.

Abstract: To be able to disengage the contacts of a switch in the event of a breakage of the snap spring or if the contacts become melted together, a pivotable resetting member in the form of a two-armed lever is provided. One arm of the lever is associated with the inside end of an operating plunger, while its other arm is associated with the end of a slide of the switch. While being displaced from its initial position into the switched position, the slide pushes the resetting member and the end of the operating plunger moved thereby away from the respective arm of the resetting member. By pushing the operating plunger against the actuator, the end of the plunger acts against the arm of the resetting member whose pivotal motion then causes the slide to be pushed into its initial position.

Abstract: An electrical switch comprises, in addition to its switching mechanism or mechanisms, a potentiometer including a potentiometer plate and a slider which is advantageously moved/simultaneously with the actuation of the switching mechanisms. The switch requires terminal elements not only for the switching mechanism or mechanisms but also for this potentiometer. Consequently, an electrical connection must be provided within the switch between the inner ends of the terminal elements and the potentiometer plate. In accordance with the invention, the potentiometer plate is connected to the terminal elements by slip-in attachment which not only ensures a safe hold but also effects the electrical contact. To this end, the potentiometer plate is inserted into slot-shaped seats of the terminal elements, which are prevented from being unduly enlarged by suitable means.

Abstract: A pushbutton switch, suitable particularly for keyboards of business machines substantially comprises a cup-shaped casing which may be made in two parts and has its cup edge side closed by a pushbutton. Against the side of the button, the upper end of a return spring is applied whose lower end bears against an angle leg of a contact member, and which is secured against buckling preferably by a holding member. Another angle leg of the contact member applies against a shank surface which is provided with a shoulder for permitting an abrupt tilting of the contact member upon pushing the button. Movable contacts may be provided on one or the other angle legs of the contact member. The fixed contacts are then located accordingly. The fixed contacts may be formed by end portions of connecting elements extending to the outside or by elements of a circuit board. To assemble the keyboard a plurality of such switch casings are manufactured integrally with a cover plate.

Abstract: A slide held in its initial position by a helical tension spring, carries at least one contact bridge, comprising a pair of movable contacts which cooperate with opposite contacts preferably contacts that are fixed to a housing. Between the slide and an operating plunger, a substantially C-shaped snap spring is clamped in inclined position, by which the slide and the operating plunger are retained in their initial positions.Upon shifting the operating plunger in a selected direction, the inclined spring is righted and, after passing its neutral position, displaces the slide and the parts supported thereon abruptly against the fixed contacts.A particularly advantageous switching characteristic (shortening of the operating distance in forward switching) is obtained by providing that the side portions of the C-shaped snap spring butt against a stop in the housing, so that the tilting radius of the snap spring is reduced.