Patent ID: 11873868
Assignee: HORTON, INC.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 20:
21. A method of transmitting magnetic flux through a viscous friction clutch to operate a valve assembly, the viscous friction clutch including a rotor and a housing that are each rotatable and also a shaft that is rotationally fixed to the rotor, wherein the valve assembly controls a volume of shear fluid present in a working chamber in order to selectively control a degree of viscous frictional engagement between the rotor and the housing, the method comprising:
energizing an electromagnetic coil located at an exterior of the housing of the viscous friction clutch, wherein the electromagnetic coil is rotationally stationary;
transmitting magnetic flux from the electromagnetic coil to a coil housing that at least partially surrounds the electromagnetic coil;
transmitting magnetic flux from the coil housing to the shaft of the viscous friction clutch across a radial gap;
transmitting magnetic flux from the shaft to an armature of the valve assembly across an axial gap in an area of magnetic attraction;
transmitting magnetic flux from the armature to a flux guide part across a gap, wherein the flux guide part is made of a ferromagnetic material;
transmitting magnetic flux along the flux guide part between axially opposite front and rear sides of the rotor of the viscous friction clutch;
transmitting magnetic flux from the flux guide part to the coil housing across a flux gap that includes a non-ferromagnetic portion of the housing of the viscous friction clutch; and
transmitting magnetic flux from the coil housing back to the electromagnetic coil.