Wheel bearing apparatus

A wheel bearing apparatus having an outer side positioned outside of a vehicle body and an inner side position inside the vehicle body comprising:

• an outer member has an inner circumference and an outer circumference with a body mounting flange, the flange to be mounted on a knuckle that forms a portion of a suspension apparatus, the outer member inner circumference includes double row outer raceway surfaces;
• an inner member including a wheel hub and an inner ring, the wheel hub includes a first end with a wheel mounting flange, the wheel hub has an outer circumference that includes one inner raceway surface opposing one of the outer raceway surfaces of the double row outer raceway surfaces, a cylindrical portion axially extends from the inner raceway surface, and the inner ring is press-fit onto the wheel hub, an outer circumference of the inner ring includes a second inner raceway surface opposing the other outer raceway surface of the double row outer raceway surfaces;
• double row rolling elements freely rollably accommodated between the outer and inner raceway surfaces of the outer and inner members;
• and
• a seal mounted within an outer-side opening in an annular space formed between the outer member and the inner member;
• the seal is formed from an integrated seal comprising a metal core and a sealing member, the metal core is fit into an outer-side end inner circumference of the outer member, the sealing member is integrally adhered to the metal core by vulcanized adhesion, the sealing member includes a plurality of sealing lips;
• the metal core is press-formed from a steel sheet and comprises a cylindrical fitting part, a radial inner part, an annular flat part, and a cylindrical flange part, the cylindrical fitting part fit into the outer-side end inner circumference of the outer member, the radially inner part is bent from the fitting part and extends radial inward, the annular flat part extends radially outward from an outer-side end of the fitting part and contacts the outer-side end face of the outer member, and the cylindrical flange part is formed on the radially outermost end of the annular flat part and extends toward the outer member;
• the sealing member is formed from synthetic rubber and adhered to the metal core in a range from the radially innermost end of the radially inner part to the flanged part;
• the sealing member comprises a first side lip, a second side lip, a third side lip and a radial lip, the first side lip is inclined radially outward from the radially inner part of the metal core, the first side lip opposes an inner-side base of the wheel mounting flange, via an axial gap, the second side lip is formed radially inward of the first side lip, the second side lip is in sliding contact with a surface as the second side lip extends toward the wheel mounting flange, via an axial interference, the radial lip extends from a base of the second side lip and is inclined radially inward toward the inner side, the third side lip is adhered to the flanged part of the metal core, the third side lip covers the entire surface of the flanged part and extends radially outward from its base toward the wheel mounting flange;
• a tip end of the third side lip is formed with a vertically flat surface opposing the inner-side surface of the wheel mounting flange via an axial gap to form a first labyrinth seal;
• and
• a second labyrinth seal is formed at a position between the first labyrinth seal and the first side lip opposing the inner-side base of the wheel mounting flange via an axial gap.