Abstract: A magnetorheological fan coupling (10) having a fan-drive subassembly (12), an electromagnet subassembly (14), and a magnetic medium (16). The fan-drive subassembly (12) includes an output member (22) and an input member (20) rotatably mounted around the output member (22) with the magnetic medium (16) therebetween. The magnetic medium (16) has a shear stress that can be adjusted by a magnetic flux (24) for transferring torque between the input member (20) and the output member (22). The electromagnet subassembly (14) includes a stationary electromagnet coil (62) for adjusting the shear stress of the magnetic medium (16) and regulating a torque transferred between the input member (20) and the output member (22).

Abstract: A hydraulically controlled fan drive system (12) having a method of engagement includes a housing assembly (20) containing a hydraulic fluid (48) and an engaging circuit (36). The engaging circuit (36) includes a pitot tube (152) coupled within the housing assembly (20) that receives at least a portion of the hydraulic fluid (48). An engaging circuit (36) engages the housing assembly (20) to a fan shaft (44) in response to supply of the hydraulic fluid (48) from the pitot tube (152).

Abstract: A magnetorheological fan coupling (10) having a fan-drive subassembly (12), an electromagnet subassembly (14), and a magnetic medium (16). The fan-drive subassembly (12) includes an output member (22) and an input member (20) rotatably mounted around the output member (22) with the magnetic medium (16) therebetween. The magnetic medium (16) has a shear stress that can be adjusted by a magnetic flux (24) for transferring torque between the input member (20) and the output member (22). The electromagnet subassembly (14) includes a stationary electromagnet coil (62) for adjusting the shear stress of the magnetic medium (16) and regulating a torque transferred between the input member (20) and the output member (22).

Abstract: A magnetorheological fan coupling (10) having an inverted construction with an input member (18) rotatably mounted to an output member (20). The input member (18) defines a fluid chamber (50) with the output member (20) rotating therein and a magnetic medium (52) between the output member (20) and the input member (18). The coupling (10) further includes an electromagnet subassembly (14) actuated by a controller (82) for adjusting the shear stress of the magnetic medium (52) and regulating the amount of torque transferred from the input member (18) to the output member (20).

Abstract: A hydraulically controlled fan drive system (12) having a method of engagement includes a housing assembly (20) containing a hydraulic fluid (48) and an engaging circuit (36). The engaging circuit (36) includes a pitot tube (152) coupled within the housing assembly (20) that receives at least a portion of the hydraulic fluid (48). An engaging circuit (36) engages the housing assembly (20) to a fan shaft (44) in response to supply of the hydraulic fluid (48) from the pitot tube (152).

Abstract: A hydraulically controlled fan drive system for controlling the cooling of an engine and having a method of engagement includes a housing assembly containing a hydraulic fluid and an engaging circuit. The engaging circuit includes a pitot tube coupled within the housing assembly that receives at least a portion of the hydraulic fluid as the housing assembly rotates to drive a clutch pack (and coupled fan) via static pressure. A fluid controller having binary control adjusts the static pressure within the pitot tube at a given rotational speed, thereby controlling the engagement of the clutch pack to a fully engaged drive (utilizing friction type engagement), a fully disengaged drive, and at least two partially engaged clutch positions (i.e. partially engaged utilizing a wet viscous type clutch engagement). To control static pressure release, the fluid controller may utilize a dual spool system valving arrangement or a parallel fixed orifice binary control.

Abstract: The control of the coolant flow is accomplished through valving or by adjusting the pumping speed of a water pump and a water motor, or a combination of all three elements. During normal operation, where engine cooling is not required, the speed control coupling maintains a slow and constant water pump speed at all engine-operating speeds. The valve is maintained to stop coolant flow from entering the radiator while allowing coolant to flow through a heater. If engine cooling is required, the valve is actuated such that coolant is circulated to the engine and through the radiator. If air conditioning is required, the speed control coupling simply increases the water pump speed and the fan speed while the valve is set to bypass coolant flow to the engine. If air conditioning and engine cooling are required, the valve is actuated to allow coolant flow to the engine.

Abstract: A stator and diffuser assembly is introduced between an engine cooling fan and engine. The stator acts increase the static efficiency per unit airflow of the axial fan by reducing the rotational component of air traveling through the fan and by directing the airflow in an axial direction towards the engine. The diffuser acts to increase the static efficiency per unit airflow of the axial fan used by decelerating the airflow, thereby providing more airflow to the engine at a given fan rotational speed. The stator and diffuser assembly thus decreases the amount of horsepower necessary to drive the fan at a given rotational speed and reduces noise.

Abstract: A flexible metal disk used to mount the fan to the fan drive. The metal disk is a resilient mounting, and as such reduces vibration levels between the fan and fan drive, thereby preventing damage to various components within the cooling system. The flexible metal disk also functions to self align the fan and the fan drive. The flexible metal disk is also durable, and therefore offers improved creep and deterioration resistance as compared with typical elastomeric mountings. In another preferred embodiment, multiple flexible metal disks may be coupled together and used to mount the fan to the fan drive to provide additional damping as compared with single disk systems.

Abstract: A stator and diffuser assembly is introduced between an engine cooling fan and engine. The stator acts increase the static efficiency per unit airflow of the axial fan by reducing the rotational component of air traveling through the fan and by directing the airflow in an axial direction towards the engine. The diffuser acts to increase the static efficiency per unit airflow of the axial fan used by decelerating the airflow, thereby providing more airflow to the engine at a given fan rotational speed. The stator and diffuser assembly thus decreases the amount of horsepower necessary to drive the fan at a given rotational speed and reduces noise.

Abstract: An electronically-controlled viscous fan drive having a one-piece accumulator and reservoir located on the top side of the clutch. The accumulator also has a low pressure and high pressure fill hole for allowing movement of viscous fluid from the reservoir to a anti-bleedback chamber and into the operating and working chamber of the coupling during normal operation. A radially balance valve disk having a step up feature coupled to a spring and an actuator electronically controls movement of viscous fluid from the reservoir to the anti-bleedback chamber through the fill holes by energizing or deenergizing the spring based on engine operating conditions. The valve disk may be a one-piece or two-piece design. The accumulator is designed to prevent morning sickness associated with the flow of viscous fluid from the reservoir to the operating chamber during engine off situations.

Abstract: An electronically-controlled viscous fan drive having a one-piece accumulator and reservoir located on the top side of the clutch. The accumulator also has a low pressure and high pressure fill hole for allowing movement of viscous fluid from the reservoir to a anti-bleedback chamber and into the operating and working chamber of the coupling during normal operation. A radially balance valve disk having a step up feature coupled to a spring and an actuator electronically controls movement of viscous fluid from the reservoir to the anti-bleedback chamber through the fill holes by energizing or deenergizing the spring based on engine operating conditions. The valve disk may be a one-piece or two-piece design. The accumulator is designed to prevent morning sickness associated with the flow of viscous fluid from the reservoir to the operating chamber during engine off situations.

Abstract: A flexible metal disk used to mount the fan to the fan drive. The metal disk is a resilient mounting, and as such reduces vibration levels between the fan and fan drive, thereby preventing damage to various components within the cooling system. The flexible metal disk also functions to self align the fan and the fan drive. The flexible metal disk is also durable, and therefore offers improved creep and deterioration resistance as compared with typical elastomeric mountings. In another preferred embodiment, multiple flexible metal disks may be coupled together and used to mount the fan to the fan drive to provide additional damping as compared with single disk systems.

Abstract: An electronically-controlled viscous coupling is coupled to a water pump to control the coolant flow rate of engine coolant to an engine at a given engine speed to maximize fuel economy and minimize emissions. The viscous coupling has a stationary electrical coil that, when excited by electrical current, induces the driven disk to flex away from an input disk within the viscous, thereby increasing the size of the shear area, thereby decreasing the amount of torque produced to drive the water pump shaft and impellers that control the coolant flow rate. A carrier coupled to the back of the driven disk maximizes the amount of flex allowed to the driven disk, thereby assuring a maximum decrease in rotational speed of the impellers at a given engine speed and ensuring that the driven disk does not contact the stationary coil.

Abstract: An electronically-controlled viscous coupling is coupled to a water pump to control the coolant flow rate of engine coolant to an engine at a given engine speed to maximize fuel economy and minimize emissions. The viscous coupling has a stationary electrical coil that, when excited by electrical current, induces the driven disk to flex away from an input disk within the viscous, thereby increasing the size of the shear area, thereby decreasing the amount of torque produced to drive the water pump shaft and impellers that control the coolant flow rate. A carrier coupled to the back of the driven disk maximizes the amount of flex allowed to the driven disk, thereby assuring a maximum decrease in rotational speed of the impellers at a given engine speed and ensuring that the driven disk does not contact the stationary coil.

Abstract: A fan drive assembly including a cooling fan (11) and a fluid coupling device (13). The cooling fan includes a fan hub (17), a spider (15), and a plurality of fan blades (19). The coupling device has an output coupling assembly (21) including a body (23) and a cover (25). The body (23) includes preferably only three mounting portions (67), each being disposed immediately adjacent an outer periphery of the body. Each of the mounting portions (67) defines the necessary machining chucking surfaces (73), and a spider mounting surface (75) including a pilot surface (77) engaging the pilot diameter (79) of the spider (15). The body (23) includes cooling fins (61) covering substantially all of the rearward surface (59) of the body not covered by the mounting portions. The fan hub (17) also includes a rearwardly extending air dam portion (81), limiting localized radial air flow.

Abstract: An electronically-controlled viscous coupling is coupled to a water pump to control the coolant flow rate of engine coolant to an engine to maximize fuel economy and minimize emissions while preventing pump cavitation and possible water pump damage. The viscous coupling controls the rotational speed of a water pump shaft that is used for moving engine coolant through a cooling system as a function of engine speed and engine temperature. The viscous coupling has a stationary electrical coil that, when excited by electrical current, closes valve members which prevent the viscous fluid from entering the working chamber, thereby preventing the creation of torque to drive the water pump shaft.

Abstract: A fan drive assembly including a cooling fan (11) and a fluid coupling device (13). The cooling fan includes a fan hub (17), a spider (15), and a plurality of fan blades (19). The coupling device has an output coupling assembly (21) including a body (23) and a cover (25). The body (23) includes preferably only three mounting portions (67), each being disposed immediately adjacent an outer periphery of the body. Each of the mounting portions (67) defines the necessary machining chucking surfaces (73), and a spider mounting surface (75) including a pilot surface (77) engaging the pilot diameter (79) of the spider (15). The body (23) includes cooling fins (61) covering substantially all of the rearward surface (59) of the body not covered by the mounting portions. The fan hub (17) also includes a rearwardly extending air dam portion (81), limiting localized radial air flow.

Abstract: A fan drive assembly including a cooling fan (11) and a fluid coupling device (13). The cooling fan includes a fan hub (17), a spider (15), and a plurality of fan blades (19). The coupling device has an output coupling assembly (21) including a body (23) and a cover (25). The body (23) includes preferably only three mounting portions (67), each being disposed immediately adjacent an outer periphery of the body. Each of the mounting portions (67) defines the necessary machining chucking surfaces (73), and a spider mounting surface (75) including a pilot surface (77) engaging the pilot diameter (79) of the spider (15). The body (23) includes cooling fins (61) covering substantially all of the rearward surface (59) of the body not covered by the mounting portions. The fan hub (17) also includes a rearwardly extending air dam portion (81), limiting localized radial air flow.

Abstract: The control of the coolant flow is accomplished through valving or by adjusting the pumping speed of a water pump and a water motor, or a combination of all three elements. During normal operation, where engine cooling is not required, the speed control coupling maintains a slow and constant water pump speed at all engine-operating speeds. The valve is maintained to stop coolant flow from entering the radiator while allowing coolant to flow through a heater. If engine cooling is required, the valve is actuated such that coolant is circulated to the engine and through the radiator. If air conditioning is required, the speed control coupling simply increases the water pump speed and the fan speed while the valve is set to bypass coolant flow to the engine. If air conditioning and engine cooling are required, the valve is actuated to allow coolant flow to the engine.