the present inventors regarding temperature versus distance to the heat focus in order to know the temperature distribution curve and therefore its gradient which is what finally determines the zones to be occupied by each of the different plastic i e the dimensions of the different portions 1 2 and 12 and also the boundaries between said zones this temperature distribution analysis has been conducted on a support made of polyamide and is represented in the graph of fig9 where the thicker wave represents the measured values and the thinner wave represents the average profile thereof as shown the temperature distribution profile responds approximately to a gaussian curve profile darker wave which is to be expected given the analysed distances are relatively short and the support material polyamide is completely uniform in its characteristics they have been measured temperatures around 200 u00b0 c in cases of normal operation and up to 250 u00b0 c in conditions with some abnormality such as conditions associated to a high number of switching actions and some deterioration of the material surface this temperature distribution gives an approximate gradient of temperature decreasing of about 30 u00b0 c mm this value is used to establish the boundaries of the zones of different material i e the boundaries between portions 1 2 and 12 in relation to the estimated maximum temperature point in a practical case assuming that the electrical current will come to the electromechanical switch through electric cables coupled to for example faston connectors connected to the metallic terminals 5 a and 5 b attached to.