Gm Global Technolgoy Operations, Inc.

Swaminathan Gopalswamy

Gary Lee Jones

Samuel Miller Linzell

William Charles Kruckemeyer

Bruce Jeffrey Clingerman

Donald H Keskula

Gary Lee Johnston

Shankar Akella

Michael Leslie Oliver

An airflow control system and method for a fuel cell includes a compressor that supplies air to a storage chamber for storing the air. Fuel cell subsystems are connected to the air storage chamber. Each of the fuel cell subsystems includes a flow controller and flow sensor. A sensor measures air pressure in the storage chamber. A controller polls the flow controllers of the fuel cell subsystems for a minimum required air pressure for the fuel cell subsystems. The controller selects a highest minimum required air pressure. The controller controls the compressor to provide the highest minimum required pressure in the air storage chamber. The air storage chamber includes tubing, a manifold or both.

Air distribution method and controller for a fuel cell system

A magnetorheological fluid fan clutch effects modulated rotational motion transmission between a rotatable input shaft carrying an input clutch plate and a housing having a front cover and a rear cover forming a cavity about the input clutch plate wherein the front and rear covers operate as output clutch plates. A nonmagnetic spacer is positioned between the front and rear covers and radially outside the input clutch plate. A bearing supports the housing on the input shaft through the rear cover so that the input clutch plate is rotatable on the input shaft relative to the housing. Magnetorheological fluid is carried in the cavity, through which torque is variably transferred between the input clutch plate and the housing. A coil is positioned radially outside the nonmagnetic spacer and carries a variable electrical current to effect a variable magnetic field across the input clutch plate and through the magnetorheological fluid providing modulated torque transmission between the input clutch plate and the housing.

Magnetorheological fluid fan clutch

A split rotor cooling fan clutch includes an input member that is constantly driven at engine speed, or at some selected proportion thereof. An output member is journaled on the input member so as to be supported thereon in a substantially nonrotating state when decoupled and alternately, to be concentrically rotatable in concert therewith at a variety of speeds. A space presented between the input and output members contains a quantity of magnetorheological fluid. An engagement mechanism includes the split rotor and coil, with a ferromagnetic element positioned to define an operative gap between the rotor and the ferromagnetic element. The coil is selectively energized with a given current to result in a torque transfer between the input and output elements that provides a rotational speed of the fan tailored to the cooling requirements of the associated engine. Internal heat generation is managed electronically to prevent overheating.

Split rotor cooling fan clutch

A magnetorheological fluid fan clutch effects modulated rotational motion transmission between a rotatable input shaft carrying an input clutch plate and a housing having a front cover and a rear cover forming a cavity about the input clutch plate wherein a core carried in the front and rear covers operates as output clutch plates. Bearings support the housing on the input shaft through the front and rear covers so that the input clutch plate is rotatable on the input shaft relative to the housing. Magnetorheological fluid is carried in the cavity, through which torque is variably transferred between the input clutch plate and the housing. A coil is positioned radially outside the non-magnetic spacer and carries a variable electrical current to effect a variable magnetic field across the input clutch plate and through the magnetorheological fluid providing modulated torque transmission between the input clutch plate and the core.

Magnetorheological fluid clutch with minimized reluctance

A magnetorheological clutch for controllable torque transmission includes a housing defining a cavity with a rotary input element carrying at least one input clutch plate extending radially in the cavity. A rotary output element carrying at least one output clutch plate extends radially into the cavity adjacent the input clutch plate with a gap defined between the input clutch plate and the output clutch plate. A core formed of magnetically permeable material has a pair of side plates extending radially across the housing. A coil effective to establish an electromagnetic field is carried against the core. Magnetorheological fluid is carried in the cavity within the gap and is responsive to the electromagnetic field that is established by the coil through the core so that torque is transferred from the input clutch plate to the output clutch plate through the magnetorheological fluid. A series of radially extending cooling fins are positioned in the cavity, radially inside the input clutch plate and the output clutch plate so that generated heat is dissipated through the cooling fins by exposure to a circulating coolant fluid flowing about the cooling fins that enters and exits the cavity through a coolant flow path. Heat expansion of the magnetorheological fluid is accommodated by a thermal expansion chamber.

Growing community of inventors

Rochester Hills, MI, United States of America

Swaminathan Gopalswamy