A driving force transmission control device includes a driving force transmission device configured to press a friction clutch by an actuator and a controller configured to control the driving force transmission device. The controller calculates a torque command value indicating a driving force to be transmitted from a rotating member on an input side to a rotating member on an output side based on information of a vehicle. The controller sets an electric current command value according to a magnitude and an amount of time change of the torque command value. The electric current command value is a target value of an electric current. The controller performs electric current feedback control such that an electric current corresponding to the calculated electric current command value is supplied to the actuator.

An electromagnetic clutch assembly may include a first clutch plate, a second clutch plate, and a synchronizer. The second clutch plate may define an aperture. A portion of the synchronizer may be configured to extend through the aperture. In the absence of a magnetic field, the first clutch plate and the first surface of the second clutch plate may define an air gap and the portion of the synchronizer may extend into the air gap. In response to a first magnetic field, the portion of the synchronizer may contact the first clutch plate. In response to a second magnetic field, the portion of the synchronizer may translate in the aperture toward the second clutch plate and the first clutch plate and the second clutch plate may close the air gap.

An example electromagnetic clutch assembly includes a rotatable portion and a stationary portion. The rotatable portion includes a field winding and a clutch body, and the stationary portion includes an exciter winding that is inductively coupled to the rotatable portion and is operable to energize the field winding. The field winding is operable, when energized, to provide a magnetic field that causes engagement or disengagement between the clutch body and an armature body. A method of operating an electromagnetic clutch assembly is also disclosed.

Provided is an electromagnetic clutch capable of shortening, even in a low temperature atmosphere, the fuse reaction time from when a rotating shaft is locked, while preventing or suppressing malfunction of the thermal fuse. An electromagnetic clutch 1 is equipped with a rotor 2, an armature 3, an electromagnetic coil unit 4, a thermal fuse 5, and a thermally actuated switch 6. The thermally actuated switch 6 is connected in series to an electromagnetic coil 41 of the electromagnetic coil unit 4 along with the thermal fuse 5. When a temperature of the thermally actuated switch 6 exceeds a switching temperature (predetermined temperature) Ts, the thermally actuated switch 6 is displaced in an electric power supply OFF direction, and thereafter, it is displaced in an electric power supply ON direction due to a reduction in temperature. The thermally actuated switch 6 turns ON/OFF the electric power supply to the electromagnetic coil 41 such that the thermal fuse vicinity temperature T1 does not exceed the operational temperature Tf of the thermal fuse 5 due to self-heating of the electromagnetic coil 41 itself generated by the electric power supplied to the electromagnetic coil 41, thereby preventing malfunction of the thermal fuse 5 due to self-heating of the electromagnetic coil 41.

In an aspect, an automotive air conditioning assembly comprising a scroll compressor and a wrap spring clutch. The wrap spring clutch enables the use of a comparatively smaller pulley (a diameter of at most 85 mm) which comparatively increases the compressor speed and hence cooling capacity at a given engine speed. The clutch requires low power (e.g. less than 5 Watts) for continuous operation.

A pump includes a stator and a rotor axially between a fluid inlet section and a fluid outlet section. The stator includes a plurality of radially inwardly extending legs; and a plurality of electrical windings disposed about the radially inwardly extending legs. The attenuating circuit includes a capacitor electrically wired in parallel with each winding and at least one switch electrically connected to the capacitor. During energization of the electrical winding, the switch electrically connects the capacitor to an electrical ground and the electrical power source creates a voltage in the capacitor. Following a de-energization of the plurality of electrical windings, the switch isolates the capacitor from the electrical ground and the capacitor discharges the voltage through the electrical winding, creating a decaying oscillating current that attenuates residual magnetization in the winding.

A fishing machine includes a rotary drum for winding a fishing line, capable of rotating in a reeling direction and in a unreeling direction, a drive motor for rotating the rotary drum in the reeling direction and in the unreeling direction, and an electromagnetic clutch for transmitting the rotation of the drive motor to the rotary drum. The electromagnetic clutch is capable of variably setting a transmitting torque of rotation, and the transmitting torque is set to a value for cancelling a mechanical load in the unreeling direction of the fishing machine.

A transmission control unit for a wedge clutch, comprising a controller configured to send one or more signals to a switch connected to the wedge clutch, the switch being configured to demagnetize the wedge clutch by sending current in a first direction to a coil of the wedge clutch.

A rotational coupling device includes an armature configured for coupling to a shaft for rotation with the shaft about an axis, but axially movable relative to the shaft. An electromagnet assembly is disposed on one side of the armature and fixed against rotation. A collar is disposed on the opposite side of the armature. The collar is configured for rotation with the shaft, but fixed against axial movement relative to the shaft and includes a permanent magnet. When a current having a first polarity is provided to the electromagnet assembly, the armature moves in one axial direction into engagement with a member of the coupling device to transmit a torque between the member and the armature. The permanent magnet urges the armature in the opposite axial direction to disengage the armature from the member when the current is not provided to the electromagnet assembly.

A clutch current control circuit may include as a circuit for controlling a current of a clutch connected to a compressor, a strain gauge, wherein a resistance value of the strain gauge is varied according to the movement amount of an Electric Control Valve (ECV) shaft; a switching element of performing a switching operation by comparing a gate-source voltage determined according to a change in the resistance value of the strain gauge and the threshold voltage, and allowing a flow of a first clutch current to generate by a first switching operation state; and a resistor connected in parallel with the switching element, and allowing a flow of a second clutch current to generate by a second switching operation state of the switching element.