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.

A cooling control system for a working machine includes a fan, a housing to which the fan is attached, a prime mover having an output shall, a rotor to be rotated by a rotating power of the output shaft and to be rotated with the housing by a fluid introduced to a gap formed between the housing and the rotor, a fluid setting circuit to set an introduction amount of the fluid introduced to the gap, and a control device to control the fluid setting circuit to control the fan. The control device includes a setting circuit to set a target rotation speed of the fan based on a responsiveness of an actual rotation speed of the fan at time of changing of the target rotation speed of the fan.

A viscous fluid shear device having a housing, a rotor, which is rotatable in the housing, and a wiper that is coupled to the housing. The housing defines a scavenge conduit and a nozzle. Viscous fluid that clings to the circumference of the rotor during operation of the viscous fluid shear device is driven through the nozzle and directed by the wiper into the scavenge conduit.

A viscous damper has an inertial mass in the form of a tubular member that is applicable for dissipating (removing) destructive torsional vibration in power transmitting shaft assemblies. A viscous fluid contained between moving surfaces is sheared, thereby producing frictional heat which is then allowed to transfer across the moving surfaces to the ambient surroundings. Surfaces of the inertial mass and housing are arranged with respect to each other to provide high shear rate and energy dissipation (damping) is obtained within a small volume.

A viscous damper has an inertial mass in the form of a tubular member that is applicable for dissipating (removing) destructive torsional vibration in power transmitting shaft assemblies. A viscous fluid contained between moving surfaces is sheared, thereby producing frictional heat which is then allowed to transfer across the moving surfaces to the ambient surroundings. Surfaces of the inertial mass and housing are arranged with respect to each other to provide high shear rate and energy dissipation (damping) is obtained within a small volume.

An electromagnetic coil assembly (34) includes a coil sub-assembly (34C) and a tower sub-assembly (34T). The coil sub-assembly includes a coil housing (70) having a first opening (70-4A; 70-4B), a coil winding (72), a tower mount (74) having a base (74-1) adjoining the first opening and extending along a first surface (70I) of the coil housing, and a first mount bushing (76A; 76B) secured to the base. The first mount bushing is electrically connected to the coil winding. The tower sub-assembly includes a tower housing (90) positioned at a second surface of the coil housing located opposite the first surface, a first tower bushing (96A; 96B) electrically connected to the first mount bushing, and a first fastener (98A; 98B) securing the first tower bushing to the first mount bushing. The first fastener is engageable to the first mount bushing from proximate the second surface of the coil housing.

This disclosure relates to a fluid friction clutch having a housing, a clutch disc which is arranged at one end of a shaft which is mounted within the housing, a working chamber which is configured between the housing and the clutch disc, a storage chamber for clutch fluid, and at least one feed duct which leads from the storage chamber to the working chamber. Moreover, a pressure relief device for discharging clutch fluid from the feed duct into the storage chamber is provided.

An internal combustion engine including a cooling liquid circuit, which is connected to a cylinder head and an engine block of the internal combustion engine and which includes a cooling liquid pump. The cooling liquid pump includes a drive shaft and is capable of conveying cooling liquid in the cooling liquid circuit. Further, the internal combustion engine includes a Visco clutch. The Visco clutch is arranged for the drive by the internal combustion engine. The Visco clutch includes a clutch fluid for torque transmission. At the output side, the Visco clutch is connected to the drive shaft of the cooling liquid pump. The drive shaft of the cooling liquid pump include at least one heat pipe. The heat pipe is in heat exchange with the clutch fluid as a heat source and the cooling liquid as a heat sink.

A clutch device for a clutch system has an input member that rotates at a first speed. A friction drive system is disposed between the input member and an output member. The clutch device is selectively movable by a fluid actuator assembly, between an engaged position in which the friction drive system drives the output member to rotate at the first speed, and a disengaged position in which a viscous drive system rotates the output member at a second speed slower than the first speed. A variable viscous fluid supply assembly includes a viscous fluid storage chamber, a valve, and a valve actuator that selectively drives the valve to move between an open position and a closed position to control an amount of viscous fluid available to the viscous drive system, thereby varying the second speed.

A fluid friction clutch may include a rotatably mounted shaft, a drive disk arranged on the shaft in a rotationally fixed manner, a driven body rotatably arranged on the shaft, and a ring-shaped transfer region disposed between the drive disk and the driven body. The transfer region may be configured to receive a viscous fluid via which the drive disk is couplable to the driven body for transferring a torque. The transfer region may be defined by a ring-shaped first groove profile of the drive disk and a ring-shaped second groove profile of the driven body that engage one another axially. The clutch may also include a storage chamber fluidically connected to the transfer region via an inflow path and via a return path. The return path may include a first retaining body and a second retaining body arranged radially offset relative to one another by an arc angle.