Marquardt Gmbh

J. & J. Marquardt

Alois Schaffeler

Uwe Stratmann

An electrical switch (1) is proposed which consists of a lower housing component (3) and an upper housing component (2). In receptacles (24) of the lower housing component (3) contact lugs (23', 23') with a normally closed contact (29', 29') are arranged. In the upper housing component (2) a contact element with a switching contact (22) is arranged. The contact element is moved, via a pressure spring (17) and a slider rod (9) to which an actuation element (5) is coupled, so as to flip between the off-position and on-position. At the contact lug (23') which is arranged on the side of the lower housing component (3) facing away from the contact element in the off-position, an arc extinction lug (32) which consists of an extension is attached to the normally closed contact (29').

Electrical switch

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.

Electrical snap switch with double arm resetting lever

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.

An electric switch comprises a switch housing having a contact arm pivotally mounted on a conductive bearing. The contact arm includes a movable contact which is disposed in the housing to engage with a fixed contact of the housing in one position of the contact arm. It also includes a hook shaped end which engages on a cam surface of a slider portion of an actuating member. The contact arm is loaded by a tension spring which is mounted in the housing so that it is urged in a direction to engage the moving contact thereon with the fixed contact in the housing when the slider, which is moved by the actuating member is moved so as to permit the contact arm to pivot. The switch housing advantageously includes a second housing portion with a second switching mechanism similar to the first but which is moved during the movement of the actuating member under the control of a cam slider portion of the actuating member and that it moves faster and causes engagement of its movable contact with a fixed contact in the housing faster than the other contact arm. The actuating member itself is advantageously provided with an electrical switch member which rides over a resistance so as to cut in and out a resistance to control, for example, the speed of operation of an electric motor which is first switched on by engagement of a movable contact with a fixed contact.

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Spaichingen, Germany

Alois Schaffeler