Method for the partial metal coating of plug connector contact pins, and a screen for carrying out the method

摘要

The invention relates to a method for the partial metal coating of plug connector contact pins, in which the plug connector contact pins are held in a pin strip at their upper end and are guided with their lower ends which are to be coated flowing through a spray bath or wave bath, and also relates to the associated screen, which is to be pushed onto the pins. The pin contacts of the plug connectors are provided with a galvanically deposited noble-metal layer, because of the required reliability, in order that the specified electrical contact resistance does not exceed a maximum value. However, this design requirement does not need to be met to the same extent for all surfaces of the pin. In conventional methods, more noble metal is therefore consumed than is absolutely necessary for the technical application. In order to save noble metal, the invention thus provides a method in which screens (20) which are conveyed from the channel end to its start are pushed onto the pin contacts (16) by means of a plugging-on device (17) in a firmly mounted guide channel (12) above transportation wheels (14, 15) which project into the guide channel (12), run in synchronism with the contact pin strip (13) and are like gear wheels, and, after passing through a spray bath or wave bath, are stripped off again by means of a stripping device (19) and are inserted into the guide channel again in order to circulate again. <IMAGE>