Distributor for an internal combustion engine containing an apparatus for suppressing noise

A distributor for an internal combustion engine, comprising an apparatus for suppressing noise within a wide range of advance angles, said distributor comprising:

• a rotor made of insulating material having a first discharging electrode and being rotated by a driving shaft of the internal combustion engine;
• a plurality of stationary terminals fixed to an insulating support member, each stationary terminal provided with a second discharging electrode, said stationary terminals arranged around a circular locus with said rotor at the center of the circular locus, each of said second discharging electrodes being separated from said first discharging electrode by a discharging air gap through which a spark discharge is generated;
• said apparatus for suppressing noise comprising means for preventing the random motion of combustible gaseous molecules in said discharge gap when said spark discharge is generated, said apparatus for suppressing noise comprising a tubular insulating member having a first end secured in abutment with said first discharging electrode and a second end extending into said discharge gap;
• said tubular member forming a cylindrical passage in said discharge gap through which said spark discharge passes;
• said second end of said insulating member being arc-shaped, said arc-shaped second end being concentric with said circular locus.