A controller of a fan coupling device includes: an acquisition unit that acquires an acceleration parameter and a deviation parameter; a control unit that controls a regulation mechanism; a prediction unit that predicts that hunting occurs in the rotation speed of the fan, when an operating point of the fan expressed with the deviation parameter and the acceleration parameter belongs to a predicted region; and a restraining unit that executes, when the hunting is predicted to occur, a hunting restraining process of executing at least one of lowering an integral gain of a feedback control to be lower than when the hunting is not predicted to occur and increasing a derivative gain of the feedback control to be higher than when the hunting is not predicted to occur.

A viscous friction clutch includes a rotor, a housing that is rotatable relative to the rotor, a working chamber located between the rotor and the housing such that a volume of shear fluid can be selectively introduced to the working chamber to contact both the rotor and the housing, an electromagnetic coil, a valve assembly that controls the volume of the shear fluid present in the working chamber, and a flux path that magnetically links the electromagnetic coil and the valve assembly. The flux path passes through a flux guide part made of a ferromagnetic material that extends through the rotor in an interior of the viscous friction clutch and across a flux gap that traverses both an air gap and a non-ferromagnetic portion of the housing.

An apparatus for feeding or conveying grain includes (i) a conveyor for moving grain and having an input end and an output end, and (ii) a viscous clutch either directly or indirectly connected to the input end of the conveyor for transmitting torque from an input component to the conveyor in a variable manner. A method of feeding or conveying grain using the conveyor includes operating the viscous clutch to transmit torque from the input component to the conveyor.

A controller includes: a control unit configured to calculate a control command value of an opening degree of a solenoid valve to control an opening degree of the solenoid valve; and an acquisition unit configured to acquire an estimated amount and a target amount of a working fluid in a labyrinth chamber, and a rotation speed of a drive shaft. The control unit calculates a final control command value based on a feedback control command value and a feedforward control command value, and controls the solenoid valve, the feedback control command value being calculated based on deviation between the estimated amount and the target amount, the feedforward control command value being used to maintain a rotation speed of a fan constant based on the estimated amount and the rotation speed of the drive shaft.

An external control type fluid coupling includes: a drive disk fixed to a rotary shaft; a housing rotatably supported by the rotary shaft and defining an internal space; a partition plate provided in the housing and partitioning the internal space into operation and storage chambers; a supply hole formed in the partition plate and supplying a fluid from the storage chamber to the operation chamber; a valve body provided in the housing and made of a magnetic material; and an electromagnet generating an attraction force between the electromagnet and the valve body so that the valve body is displaced to a closed state, in which the center of gravity of the valve body, rotatably connected to the housing, is set such that the valve body is rotated to a side on which the supply hole is opened by a centrifugal force acting with the rotation of the housing.

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 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.

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.

Disclosed is a viscous coupling that has a housing that carries ribs that are arranged concentrically about a central axis. A rotor is provided that can rotate relative to the housing about the central axis in a predetermined direction. The rotor also carries ribs, and the ribs of the housing and the rotor are arranged in a working chamber surrounded by the housing. Also provided is a fluid reservoir. A fluid discharge line leads from the working chamber to the fluid reservoir. A wiper is moveably arranged between the housing and the rotor and scrapes fluid from the rotor and feeds it to the fluid discharge line. A stop is provided for the wiper and is arranged next to the rotor.

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.