Dustcover for a disc brake

A dustcover used in a disc brake of a vehicle having a disc rotor which is disposed in a wheel disc-rim assembly of cup shape comprising a wheel disc and a wheel rim fixed to said wheel disc, said dustcover covering said disc rotor on a side opposite to said wheel disc to protect said rotor from foreign matter entering through air collecting vents, said dustcover comprising:

• a generally circular flat plate portion extending substantially parallel to the surface of said disc rotor;
• portions defining first and second air vent openings opening frontwardly and rearwardly of the vehicle respectively and located at front and rear positions completely lower than the rotational axis of said rotor and relative to said rotational axis;
• a peripheral wall portion extending from said outer peripheral edge of said flat plate portion toward said rotor such that said dustcover as a whole is of a shallow cup shape, said dustcover being devoid of said peripheral wall portion at said front and rear positions so as to comprise said first and second vent openings;
• and
• an air collecting portion disposed at least at said first vent opening and substantially entirely accommodated within a space defined by the inner surface of said wheel disc-rim assembly such that said air collecting portion is open substantially within said space, said air collecting portion including an extension projecting radially outwardly from an outer peripheral edge of said generally circular flat plate portion and connected to said peripheral wall portion, said air collecting portion having a cross-sectional area gradually expanding in the frontward direction of the vehicle, external edges in elevation of said extension being substantially defined by a vertical line tangent to the periphery of the rotor at its front end and a horizontal line tangent to said periphery of the rotor at its lower end, the inner surface of a lower portion of said dustcover and the opposite surface of a lower portion of said rotor defining an air flow space through which a stream of air collected by and admitted into said air collecting portion during a frontward driving of the vehicle passes rearwardly in a direction along a line tangent to said periphery of said disc rotor at its lowermost point, said extension blocking foreign matter which comes toward an outer surface of said circular flat plate portion and which could otherwise enter into said air collecting portion.