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.

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.

A viscous clutch head may be replaced by selecting a viscous clutch head and a mount adapter. The viscous clutch head and the mount adapter may be selected from a group of universal modular fan drives and from a group of mount adapters. The mount adapter of a threaded type or a flange and bolt type may be selected. Depending on the viscous clutch head to be replaced, a fan adapter and/or a pilot adapter may also be selected from a group of fan adapters and from a group of pilot adapters. Accordingly, a range of models of viscous fan clutch systems may be replaced by using a limited number of parts. These parts may be stored on a tool cart. As different models of viscous fan clutch systems may be replaced using a limited number of parts, the in-stock inventory of replacement parts may be reduced.

A viscous clutch head may be replaced by selecting a viscous clutch head and a mount adapter. The viscous clutch head and the mount adapter may be selected from a group of universal modular fan drives and from a group of mount adapters. The mount adapter of a threaded type or a flange and bolt type may be selected. Depending on the viscous clutch head to be replaced, a fan adapter and/or a pilot adapter may also be selected from a group of fan adapters and from a group of pilot adapters. Accordingly, a range of models of viscous fan clutch systems may be replaced by using a limited number of parts. These parts may be stored on a tool cart. As different models of viscous fan clutch systems may be replaced using a limited number of parts, the in-stock inventory of replacement parts may be reduced.

According to one aspect, a clutch mechanism includes a control member. The control member is adapted to receive motive power and includes a first dry clutch member and a first viscous clutch member. The clutch mechanism further includes an output member that includes a second dry clutch member and a second viscous clutch member. The first and second dry clutch members form a dry clutch and the first and second viscous clutch members form a viscous clutch. The clutch mechanism further includes an actuation arm coupled to at least one of the control and output members. The actuation arm is selectively controllable to effect relative movement of the control and output members such that one of the dry and viscous clutches is selectively engaged.

Power transmission systems including clutch arrangements and systems are adapted to be used in marine and other environments. Such power transmission systems may include clutch arrangements that provide more effective power transmission capabilities as well as greater durability and longer life. Slipping clutch arrangements may effectively vary the output speed of a clutch arrangement from the speed of the engine or other driver as desired for the particular application. Various clutch arrangements also provide for greater flexibility and drive options, lighter weight, and diverse types of capabilities.

A clutch system is provided. The clutch system includes an outer unit having a surface defining an aperture in the outer unit; an inner unit disposed in the aperture, wherein a shape of the inner unit matches a shape of the aperture; a low melting point material disposed in the aperture between the inner unit and the surface of the outer unit; a heating element; a temperature sensor; and a processor in electronic communication with the heating element and the temperature sensor. The processor is configured to control the heating element thereby changing the low melting point material between a soft state and a rigid state.

The system includes: a driver; a rotating load configured to be driven into rotation by the driver; a controller, for controllably changing a rotation speed of the load; and a variable speed transmission, arranged between the driver and the load. The variable speed transmission includes a speed summing gear arrangement with a first input shaft, a second input shaft and an output shaft. The output shaft is drivingly coupled to the rotating load. The first input shaft is drivingly coupled to the driver. A continuous variable transmission device is mechanically coupled to the driver and to the second input shaft of the speed summing gear arrangement. The continuous variable transmission device is functionally coupled to the controller.

The present invention discloses a brake-by-wire actuator based on motor-magnetorheological fluid clutch. The system includes a motor, a transmission mechanism and a floating-caliper disc mechanism. The transmission mechanism includes a magnetorheological fluid clutch, a planetary gear set and a ball screw set. The ball screw set includes balls, a ball screw and a sleeve. The floating-caliper disc mechanism includes a brake pad back plate, left and right brake pads, a caliper body, a brake disc and a guide rail. The motor and the magnetorheological fluid clutch cascaded in series, the linear motion of the sleeve of the ball screw set is achieved by the magnetorheological fluid clutch and the transmission mechanism. The sleeve pushes forward the brake pad back plate of the floating-caliper disc mechanism to clamp the brake disc by left and right brake pads, which accomplishes braking. The present invention uses a brake-by-wire actuator based on motor-magnetorheological fluid clutch, which not only has the advantages of fast response and improved braking security, but also solves the problem of the motor stalling during long time braking.

The present invention discloses a brake-by-wire actuator based on motor-magnetorheological fluid clutch. The system includes a motor, a transmission mechanism and a floating-caliper disc mechanism. The transmission mechanism includes a magnetorheological fluid clutch, a planetary gear set and a ball screw set. The ball screw set includes balls, a ball screw and a sleeve. The floating-caliper disc mechanism includes a brake pad back plate, left and right brake pads, a caliper body, a brake disc and a guide rail. The motor and the magnetorheological fluid clutch cascaded in series, the linear motion of the sleeve of the ball screw set is achieved by the magnetorheological fluid clutch and the transmission mechanism. The sleeve pushes forward the brake pad back plate of the floating-caliper disc mechanism to clamp the brake disc by left and right brake pads, which accomplishes braking. The present invention uses a brake-by-wire actuator based on motor-magnetorheological fluid clutch, which not only has the advantages of fast response and improved braking security, but also solves the problem of the motor stalling during long time braking.