Abstract: A transmission system includes planetary gearing with a ring gear, a plurality of planet gears, a carrier, and a sun gear, a forward clutch operatively connected between the ring gear and carrier, a reverse brake operatively connected between the carrier and a rotationally fixed location, and a control subsystem to switch the transmission system between forward and reverse operational modes in the which the ring gear and the sun gear rotate in the same or opposite rotational directions, respectively. A control subsystem actuation stroke can actuate both the forward clutch and the reverse brake based on a common control signal.

Abstract: A clutch assembly includes a journal bracket having a center shaft, a drive feature rotatably supported on the center shaft of the journal bracket and configured to accept a torque input to the clutch assembly, a clutch pack that is controllable to selectively transmit torque between an input and an output, a housing attached to the clutch pack that includes a stub shaft, a removable connection engaged between the drive feature and the stub shaft such that torque is transmittable through the removable connection during operation of the clutch assembly, and one or more perpendicular engagement features on the stub shaft configured to accept a tool to engage and disengage the removable connection. At least one of the perpendicular engagement features is exposed to line-of-sight access from a location substantially perpendicular to an axis of rotation of the clutch pack.

Abstract: A viscous clutch includes an input member rotatable about an axis of rotation, an output member selectively rotatable about the axis of rotation, a working chamber bounded by the input member and the output member, a reservoir, a release bore that fluidically connects the reservoir to the working chamber, a leading wiper that extends into the working chamber, a leading pump bore positioned adjacent to the leading wiper that fluidically connects the working chamber to the reservoir, a trailing wiper that extends into the working chamber, and a trailing pump bore positioned adjacent to the trailing wiper and downstream of the leading pump bore that fluidically connects the working chamber to the reservoir. The trailing wiper has a width that is greater than a width of the leading wiper.

Abstract: A transmission system includes planetary gearing with a ring gear, a plurality of planet gears, a carrier, and a sun gear, a forward clutch operatively connected between the ring gear and carrier, a reverse brake operatively connected between the carrier and a rotationally fixed location, and a control subsystem to switch the transmission system between forward and reverse operational modes in the which the ring gear and the sun gear rotate in the same or opposite rotational directions, respectively. A control subsystem actuation stroke can actuate both the forward clutch and the reverse brake based on a common control signal.

Abstract: A viscous clutch includes a housing, an input device rotationally fixed to the housing, a rotor, a working chamber, a reservoir, a valve, and a quick disconnect bushing. The housing has a base, a cover, and a housing hub connected in in a rotationally fixed configuration. The input device is a pulley, a sprocket, and/or a gear. The rotor has a rotor disk and a rotor hub connected in a rotationally fixed configuration, and a central opening extends entirely through the rotor hub. The reservoir is carried by the housing and overlaps the input device in an axial direction. The quick disconnect bushing is removably secured to the rotor hub at the central opening and permits a rotationally fixed engagement between the rotor and an item driven by the clutch, such as an output shaft.

Abstract: A clutch assembly includes a journal bracket having a center shaft, a drive feature rotatably supported on the center shaft of the journal bracket and configured to accept a torque input to the clutch assembly, a clutch pack that is controllable to selectively transmit torque between an input and an output, a housing attached to the clutch pack that includes a stub shaft, a removable connection engaged between the drive feature and the stub shaft such that torque is transmittable through the removable connection during operation of the clutch assembly, and one or more perpendicular engagement features on the stub shaft configured to accept a tool to engage and disengage the removable connection. At least one of the perpendicular engagement features is exposed to line-of-sight access from a location substantially perpendicular to an axis of rotation of the clutch pack.

Abstract: A viscous clutch includes an input member rotatable about an axis of rotation, an output member selectively rotatable about the axis of rotation, a working chamber bounded by the input member and the output member, a reservoir, a release bore that fluidically connects the reservoir to the working chamber, a leading wiper that extends into the working chamber, a leading pump bore positioned adjacent to the leading wiper that fluidically connects the working chamber to the reservoir, a trailing wiper that extends into the working chamber, and a trailing pump bore positioned adjacent to the trailing wiper and downstream of the leading pump bore that fluidically connects the working chamber to the reservoir. The trailing wiper has a width that is greater than a width of the leading wiper.

Abstract: A clutch assembly includes a clutch mechanism and an energy harvesting device. The clutch mechanism includes an input member, an output member, and an actuating mechanism to govern selective torque transmission from the input member to the output member. The actuating mechanism is powered by electrical current. The energy harvesting device is electrically connected to the actuating mechanism, and the energy harvesting device is configured to scavenge available energy to generate the electrical current that powers the actuating mechanism.

Abstract: A viscous clutch includes a housing, an input device rotationally fixed to the housing, a rotor, a working chamber, a reservoir, a valve, and a quick disconnect bushing. The housing has a base, a cover, and a housing hub connected in in a rotationally fixed configuration. The input device is a pulley, a sprocket, and/or a gear. The rotor has a rotor disk and a rotor hub connected in a rotationally fixed configuration, and a central opening extends entirely through the rotor hub. The reservoir is carried by the housing and overlaps the input device in an axial direction. The quick disconnect bushing is removably secured to the rotor hub at the central opening and permits a rotationally fixed engagement between the rotor and an item driven by the clutch, such as an output shaft.

Abstract: A clutch assembly includes a clutch mechanism and an energy harvesting device. The clutch mechanism includes an input member, an output member, and an actuating mechanism to govern selective torque transmission from the input member to the output member. The actuating mechanism is powered by electrical current. The energy harvesting device is electrically connected to the actuating mechanism, and the energy harvesting device is configured to scavenge available energy to generate the electrical current that powers the actuating mechanism.

Abstract: A viscous clutch includes a shaft, a rotor disk, a housing having a base, a working chamber, a reservoir fluidically connected to the working chamber, a valve, an electromagnetic coil, and a flux guide that passes through the housing. The rotor disk includes a conductive portion made of a magnetic flux conductive material that forms a hub of the rotor disk that contacts the shaft and another portion. The base includes a hub with an axially-extending ring, and an armature of the valve is located radially outward of the axially-extending ring. The electromagnetic coil is located at an opposite side of the rotor disk from the reservoir. A magnetic flux circuit extends from the electromagnetic coil to the flux guide, then to the armature of the valve, then to the conductive portion of the rotor disk, then to the shaft, and then back to the electromagnetic coil.

Abstract: A viscous clutch includes an input member, an output member, a working chamber defined between the input member and the output member, a reservoir to hold a supply of a shear fluid, a valve that controls a flow of the shear fluid between the reservoir and the working chamber along a fluid circuit that fluidically connects the reservoir and the working chamber, a bearing, and an electromagnetic coil supported by the bearing. The electromagnetic coil includes a coil housing and a winding that forms multiple turns within an interior volume of the coil housing, wherein the coil housing has a stepped configuration to at least partially accommodate the bearing within a first step. Selective energization of the electromagnetic coil actuates the valve.

Abstract: A viscous clutch includes an input member, an output member, a working chamber, a reservoir to hold a supply of a shear fluid, an outlet, a return bore, an accumulator, and a first wall having an arcuate segment. The reservoir is connected to the working chamber by a fluid circuit, along which the outlet passes the shear fluid from the reservoir to the working chamber and the return bore returns the shear fluid pumped out of the working chamber to the accumulator. The accumulator is arranged in series with the reservoir in the fluid circuit. The first wall is positioned within the reservoir to separate a first portion from a second portion.

Abstract: A viscous clutch includes an input member, an output member, a working chamber, a reservoir to hold a supply of a shear fluid, an outlet, a return bore, an accumulator, and a first wall having an arcuate segment. The reservoir is connected to the working chamber by a fluid circuit, along which the outlet passes the shear fluid from the reservoir to the working chamber and the return bore returns the shear fluid pumped out of the working chamber to the accumulator. The accumulator is arranged in series with the reservoir in the fluid circuit. The first wall is positioned within the reservoir to separate a first portion from a second portion.

Abstract: A viscous clutch includes an input member, an output member, a working chamber defined between the input member and the output member, a reservoir to hold a supply of a shear fluid fluidically connected to the working chamber by a fluid circuit, a valve that is electromagnetically actuatable to selectively control a flow of the shear fluid along the fluid circuit, a control coil assembly, and a securing mechanism. The control coil assembly includes a modular center hub removably attached to the input member, an electromagnetic coil and a coil bearing rotatably supporting the electromagnetic coil on the modular center hub. The securing mechanism is removably attached to the input member radially inward of the working chamber and the reservoir, and includes a radially outwardly extending flange.

Abstract: A fan blade (134) includes a working region (148) having a leading edge (138) and a pressure side (136). A plurality of flow modification features (150-1 to 150-4) are positioned at the working region, including first and second flow modification features (150-1, 150-2, 150-3) each having a wedge shape with a pointed end (152) and a wider end (154), and located on the pressure side. A length of the first flow modification feature is less than a chord length of the fan blade, and the pointed end of the first flow modification feature is spaced from the leading edge. A length of the second flow modification feature is less than the chord length of the fan blade, and the pointed end of the second flow modification feature is spaced from the leading edge. The first and second flow modification features are spaced from each other to define a channel (156) therebetween.

Abstract: A viscous clutch includes an input member, an output member, a working chamber defined between the input member and the output member, a reservoir to hold a supply of a shear fluid fluidically connected to the working chamber by a fluid circuit, a valve that is electromagnetically actuatable to selectively control a flow of the shear fluid along the fluid circuit, a control coil assembly, and a securing mechanism. The control coil assembly includes a modular center hub removably attached to the input member, an electromagnetic coil and a coil bearing rotatably supporting the electromagnetic coil on the modular center hub. The securing mechanism is removably attached to the input member radially inward of the working chamber and the reservoir, and includes a radially outwardly extending flange.

Abstract: A viscous clutch (20) includes an input member (26), an output member (24), a working chamber (30) defined between the input member and the output member, a reservoir (28) to hold a supply of a shear fluid, a valve (32) that controls a flow of the shear fluid between the reservoir and the working chamber along a fluid circuit that fluidically connects the reservoir and the working chamber, a bearing (48), and an electromagnetic coil (34) supported by the bearing. The electromagnetic coil includes a coil housing (34-1) and a winding (34-2) that forms multiple turns within an interior volume (34-3) of the coil housing, wherein the coil housing has a stepped configuration to at least partially accommodate the bearing within a first step (34-4). Selective energization of the electromagnetic coil actuates the valve.

Abstract: A viscous clutch includes a shaft, a rotor disk, a housing having a base, a working chamber, a reservoir fluidically connected to the working chamber, a valve, an electromagnetic coil, and a flux guide that passes through the housing. The rotor disk includes a conductive portion made of a magnetic flux conductive material that forms a hub of the rotor disk that contacts the shaft and another portion. The base includes a hub with an axially-extending ring, and an armature of the valve is located radially outward of the axially-extending ring. The electromagnetic coil is located at an opposite side of the rotor disk from the reservoir. A magnetic flux circuit extends from the electromagnetic coil to the flux guide, then to the armature of the valve, then to the conductive portion of the rotor disk, then to the shaft, and then back to the electromagnetic coil.

Abstract: A viscous clutch includes an input member, an output member, a working chamber, a reservoir to hold a supply of a shear fluid, an outlet, a return bore, an accumulator, and a first wall having an arcuate segment. The reservoir is connected to the working chamber by a fluid circuit, along which the outlet passes the shear fluid from the reservoir to the working chamber and the return bore returns the shear fluid pumped out of the working chamber to the accumulator. The accumulator is arranged in series with the reservoir in the fluid circuit. The first wall is positioned within the reservoir to separate a first portion from a second portion.