MANUFACTURING METHOD OF CURRENT CONDUCTING CONTACT ELEMENTS Russian patent published in 2020 - IPC H01R43/12 

FIELD: electrical engineering.

SUBSTANCE: invention relates to the field of electric engineering and relates to the manufacturing method of current conducting contact elements, mainly electric brushes and coal contact inserts for current collectors of electric rolling stock, operating under conditions of high current density, considerable vibrations and impact loads. Said technical result is achieved by means of manufacturing method of current-conducting contact elements, which includes production of electro-graphised porous workpieces with finished dimensions of element, impregnation with an aqueous solution consisting of 72.8 wt % furfuryl alcohol, 2.9 wt % of orthophosphoric acid and 24.3 wt % water, first, preparing an aqueous solution of furfuryl alcohol by pouring into the impregnation bath the required amount of furfuryl alcohol, separately preparing water with addition of orthophosphoric acid, phosphoric acid solution was poured into a bath with furfuryl alcohol with vigorous stirring to obtain a density g/cm³ solution 1,120-1,130, then the bath is loaded with workpieces packed into punched boxes and held there for 2-3 hours, after which boxes with workpieces are removed from container and subjected to washing with washing, submerging boxes with workpieces from three to five times in container with water, then washed workpieces are subjected to drying at room temperature for at least 8 hours and further heat treatment in heating devices with holding for 2-3 hours at temperature 140-160°C.

EFFECT: formation of stable and stable varnish element in process of long-term operation, including with high current density in the presence of impact and vibration loads; this improves switching, reduces wear of the element during prolonged operation.

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