Wet disc brake

A wet disc brake unit for wheeled vehicle, comprising:

• a) a piston housing reciprocally mounting an annular piston for axial movement towards and away from a disc housing;
• b) said disc housing secured to said piston housing and defining a disc chamber in which a plurality of interleaved, friction and reaction plates are disposed;
• c) an annular pressure plate mounted for reciprocating movement within said disc housing towards and away from said disc chamber;
• d) spring means applying forces to said annular pressure plate urging it toward clamping engagement with said discs in said disc chamber;
• e) said disc housing defining a plurality of spring chambers, each chamber including one of said spring means and defining a bridging segment extending from an outer to an inner portion of said disc housing to provide rigidizing structure for said disc housing;
• f) one of said spring chambers defining an outlet for coolant;
• g) seal means for providing sealing engagement between a periphery of said pressure plate and said disc housing whereby coolant flow from said disc chamber, across said pressure plate is inhibited.

A wet disc brake unit for a wheeled vehicle comprising:

• a) a piston housing reciprocally mounting a piston means for movement between extended and retracted positions;
• b) a disc housing associated with said piston housing and defining a disc chamber in which a plurality of interleaved rotating and non-rotating discs are disposed;
• c) said piston means including structure for applying clamping forces to said disc pack;
• d) seal means carried by said piston means and operative to sealingly engage an adjacent disc member of said disc pack to inhibit fluid flow between said disc member and said piston means;
• and,
• e) means biasing said seal means toward engagement with said disc member, such that sealing engagement between said disc member and said seal means is maintained when said piston means is moved to its retracted position.