Abstract: A clutch mechanism is provided for a cooling fan of a size capable of fitting into the limited envelope available in an over-the-road diesel tractor. A compact housing has a belt drive input and an output connected to the fan hub. The housing includes a pressure chamber in fluid communication with a pressurized air supply and a controllable valve in the air supply line for regulating the pressure in the pressure chamber when the clutch must be operated. The air pressure actuates an internal piston to translate the clutch in a continuously variable manner between engaged and disengaged conditions.A small envelope clutch, having an outer diameter less than about 9.8 inches in diameter within the fan hub and less than about 6 inches under the belts and 7.3 inches overall so the housing may be positioned between the radiator and the engine, is capable of generating 150 foot-pounds of torque, running a 55 horsepower fan at 2100 rpm, and dissipating 10 horsepower of heat while in the slip mode.

Abstract: A clutch mechanism is provided for a cooling fan of a size capable of fitting into the limited envelope available in an over-the-road diesel tractor. A compact housing has a belt drive input and an output connected to the fan hub. The housing includes a pressure chamber in fluid communication with a pressurized air supply and a controllable valve in the air supply line for regulating the pressure in the pressure chamber when the clutch must be operated. The air pressure actuates an internal piston to translate the clutch in a continuously variable manner between engaged and disengaged conditions.A small envelope clutch, having an outer diameter less than about 9.8 inches in diameter within the fan hub and less than about 6 inches under the belts and 7.3 inches overall so the housing may be positioned between the radiator and the engine, is capable of generating 150 foot-pounds of torque, running a 55 horsepower fan at 2100 rpm, and dissipating 10 horsepower of heat while in the slip mode.

Abstract: A clutch mechanism is provided for a cooling fan of a size capable of fitting into the limited envelope available in an over-the-road diesel tractor. A compact housing has a belt drive input and an output connected to the fan hub. The housing includes a pressure chamber in fluid communication with a pressurized air supply and a controllable valve in the air supply line for regulating the pressure in the pressure chamber when the clutch must be operated. The air pressure actuates an internal piston to translate the clutch in a continuously variable manner between engaged and disengaged conditions.A small envelope clutch, having an outer diameter less than about 9.8 inches in diameter within the fan hub and less than about 6 inches under the belts and 7.3 inches overall so the housing may be positioned between the radiator and the engine, is capable of generating 150 foot-pounds of torque, running a 55 horsepower fan at 2100 rpm, and dissipating 10 horsepower of heat while in the slip mode.

Abstract: A clutch mechanism for a cooling fan of a size capable of fitting into the limited envelope available in an over-the-road diesel tractor. A compact housing has a belt drive input and an output connected to the fan hub. A wet clutch is included within the housing lubricated by oil from the engine lubrication system. The housing includes an internal positive displacement booster pump cooperating with a controllable valve in the oil return line to the engine sump. When it is desired to operate the clutch, the valve is controllably closed to restrict flow from the clutch mechanism to the engine sump line. The positive displacement pump thereupon causes an increase in pressure in a pressure chamber in the housing, which acts on an internal piston to translate the clutch in a continuously variable manner between engaged and disengaged conditions.

Abstract: The yoke of a driveline is formed with diametrically spaced and generally semi-cylindrical pockets for receiving the bearing caps of the cross of a universal joint. A notch is formed in each pocket and receives the shank of a pin whose head projects into overlying relation with the pocket and into engagement with the bearing cap to captivate the bearing cap axially in the pocket. The inner end portion of the yoke is formed on a spherical radius and is adapted to pilot into drive tubes of varying internal diameters.

Abstract: A variable speed fan drive including a cantilevered support and axially spaced bearings for mounting an input drive member with a cylinder portion and an output fan hub assembly for rotational movement relative to each other and to the support. A modulatable wet type clutch assembly is operably effective to couple the input drive member to the fan hub assembly. The output speed of the fan hub is regulated by the axial compressive force a clutch engaging member applies against interleaved members of the clutch assembly. The clutch engaging member cooperates with the cylinder portion of the input drive member to define an expansible chamber so designed that all clutch clamping forces are confined within the drive member. As such, substantially no axial thrust load is exerted on the axially spaced bearings during clutch application. The drive unit may further include cooperative elements arranged on the drive member and the fan hub assembly for preventing belt cord debris from becoming entangled thereabout.