Abstract: A method of induction heat treatment of articles having curved outer surfaces, such as differential housings. The method employs a semi-rectangular induction coil that is adapted to provide a plurality of lateral magnetic fields that are used to induce currents in, and thereby provide heat to, a portion of the curved section of the article. The method and induction coil are particularly adapted to provide an induction hardening heat treatment of a curved heat treatment portion of a differential housing. The differential housing was cast from nodular iron. The induction-hardening heat treatment comprised heating the heat treatment portion of the differential housing above the austenite transition temperature and quenching to below the martensite transformation temperature.

Abstract: A power train assembly includes a housing having a exterior wall that defines a partition between an internal chamber and the environment. Portions of the exterior wall define a housing aperture within the exterior wall. A vent plug engages the portions of the exterior wall that define the housing aperture. Portions of the vent plug define a vent aperture that is smaller than the housing aperture.

Abstract: A differential assembly having first structure, which is configured to rotate along a differential axis in response to receipt of a rotational input, a second structure, which is supported for rotation on the differential axis, a third structure which is support for rotation on the differential axis and disposed between the first and second structures and operable in an engaged condition that transmits torque between the first and second structures and a disengaged condition that inhibits torque transmission between the first and second structures, a differential gear set, which is coupled to and rotatably supported within the second structure, and a biasing mechanism, which biases the third structure in the disengaged condition. The third structure is placed in the engaged condition if a torsional magnitude of the rotational input exceeds a rotational force exerted through the differential gear set. A vehicle drive train is also provided.

Abstract: A differential assembly having first structure, which is configured to rotate along a differential axis in response to receipt of a rotational input, a second structure, which is supported for rotation on the differential axis, a third structure which is support for rotation on the differential axis and disposed between the first and second structures and operable in an engaged condition that transmits torque between the first and second structures and a disengaged condition that inhibits torque transmission between the first and second structures, a differential gear set, which is coupled to and rotatably supported within the second structure, and a biasing mechanism, which biases the third structure in the disengaged condition. The third structure is placed in the engaged condition if a torsional magnitude of the rotational input exceeds a rotational force exerted through the differential gear set. A vehicle drive train is also provided.

Abstract: A differential assembly having a first structure, which is configured to rotate along a differential axis in response to receipt of a rotational input, a second structure, which is supported for rotation on the differential axis, a third structure, which is supported for rotation on the differential axis and disposed between the first and second structures and operable in an engaged condition that transmits torque between the first and second structures and a disengaged condition that inhibits torque transmission between the first and second structures, a differential gear set, which is coupled to and rotatably supported within the second structure, and a biasing mechanism, which biases the third structure in the disengaged condition. The third structure is placed in the engaged condition if a torsional magnitude of the rotational input exceeds a rotational force that is exerted through the differential gear set. A vehicle drive train is also provided.

Abstract: A differential assembly having first, second and third structures, a differential gear set and a biasing mechanism. The first structure is configured to rotate along a differential axis in response to receipt of a rotational input. The second structure is supported for rotation on the differential axis. The third structure is supported for rotation on the differential axis and disposed between the first and second structures. The third structure can be operated in an engaged condition for transmitting torque from the first structure to the second structure and a disengaged condition for inhibiting the transmission of torque from the first structure to the second structure. The differential gear set is coupled to and rotatably supported within the second structure. The biasing mechanism biases the third structure in the disengaged condition.

Abstract: A seal assembly having a case, an annular seal member and an annular guide member. The case is adapted to be mounted to a housing within a bore. The annular seal member is coupled to the case and extends radially inward therefrom. A seal lip is formed into the annular seal member and is adapted to provide a seal between the housing and a shaft. The annular guide member is coupled to one of the case and the seal member and extends radially inward therefrom. The annular guide includes an inner tip which extends radially inward beyond the seal lip when the seal assembly is in a free state disengaged from the shaft. The inner tip of the annular guide is adapted to protect the sealing integrity of the seal lip when the seal assembly and the shaft are assembled to one another. A method for installing a seal assembly with a guide member is also provided.

Abstract: An improved housing, particularly one for an automotive differential assembly, is provided. The housing has a cast portion formed from a first material and a preformed insert member formed from a second material which is cast into the cast portion. The insert member is strategically placed in an area of the housing to selectively enhance or alter the properties of the housing at that location. The insert member may be encased in a wall of the cast portion or may extend partially through a wall of cast portion depending upon the characteristics which are being enhanced or altered. The properties which may be enhanced or altered include, for example the strength, electric or thermal conductivity, magnetic potential, chemical compatibility or the coefficient of friction.