Limiting switch

In a current limiting switch comprising, in a case:

• at least one mobile lever subject to the action of a resilient member which applies one against the other separable contact pieces directly placed at the respective ends of the lever arm carrying the mobile contact and a contact support roughly parallel to said arm;
• a thin electrically insulating screen which is placed between the lever arm and the support so that its edge is inserted between the contact pieces, while maintaining the insulation between the lever and the support, when these latter move away from each other following short circuit currents flowing in the switch, the ends of said contact supports, where said contact pieces are located in the immediate vicinity of an insulating surface of the case, so that the path of the arc is essentially tangential with respect to the movement of the mobile contact, the movement of said edge towards and against this insulating surface causing first of all shearing of the arc and then establishing complete and sealed electric insulation between two opposite chambers which the screen separates within the internal volume of the case.