A haptic operator control device for a motor vehicle has a magnetorheological brake with a brake component that is fixed to a holder and a brake component that is continuously rotatable relative to the fixed brake component. A first of the brake components extends in an axial direction and has a magnetically conductive core which extends in the axial direction, and a second brake component has a hollow shell part that encircles the first brake component. An encircling gap between the brake components is filled with a magnetorheological medium. An electrical coil is accommodated in the brake housing. At least one star contour with magnetic field concentrators formed thereon is arranged between the shell part and the core. The magnetic field concentrators project radially into the gap to define a varying gap height in a region of the star contour.

A controllable rotary brake includes two non-magnetically permeable isolating rings, a shaft, an even number of magnetic field generating portions, at least one resistance disc, and at least one magneto-rheological fluid layer. The non-magnetically permeable isolating rings are spaced apart from each other in an axial direction, and each has a bottom wall. An even number of penetrating holes are formed on the bottom wall. The shaft is rotatably inserted in and adapted to pivot relative to the non-magnetically permeable isolating rings. Two ends of each magnetic field generating portion are tightly fitted to the corresponding penetrating holes. The resistance disc is sleeved on the shaft and is spaced apart from one of the non-magnetically permeable isolating rings. The magneto-rheological fluid layer fills between the resistance disc and one of the non-magnetically permeable isolating rings and contacts the resistance disc and one end of each magnetic field generating portion.

A brake assembly is suitable for use with a vehicle wheel that has a rim rotatably mounted to an axle. The brake assembly includes a housing fixedly positioned relative to the axle and a plurality of disks disposed within the housing and fixedly positioned relative to the rim. A fluid is disposed within the housing and has a selectively variable viscosity. The viscosity of the fluid is selectively increased to increase a braking force applied to the wheel.

Disclosed herein is a bidirectional MR actuator comprising a first input member comprising a first rotor, an output member comprising a second rotor and a second input member comprising a housing having a non-magnetic portion and a magnetic portion. Each of the first input member and the output member are coupled to the second input member, the housing defining a chamber for accommodating the first rotor and the second rotor therein and further for receiving a quantity of MR fluid therewithin. The actuator further comprises a magnetic field generation assembly comprising a first coil assembly configured to selectively apply a magnetic field to a portion of the MR fluid between the first rotor and the second rotor, and a second coil assembly configured to selectively apply a magnetic field to a portion of the MR fluid between the second rotor and the magnetic portion of the housing.

This disclosure relates to a magnetorheological (MR) brake. The MR brake includes a rotor constructed at least partially of a ferromagnetic material, and a housing that supports the rotor such that the rotor and the housing are rotatable relative to each other about an axis, wherein the housing and rotor are configured such that a fluid gap is defined between the housing and the rotor, and wherein portions of the housing adjacent the rotor are constructed at least partially of a ferromagnetic material. An MR fluid is disposed in the fluid gap. A current-carrying coil is excitable to generate a magnetic field within ferromagnetic portions of the rotor and the housing and acts on the MR fluid. At least one element constructed of a material having low magnetic permeability is configured route the lines of magnetic flux through surrounding higher permeability material on opposite sides of the fluid gap.

A haptic operating device for vehicles. The device has a rotatable operating part, a magnetic field source, and a magnetorheological braking device for braking a rotational movement of the operating part. The magnetorheological braking device has two braking components which can be rotated relative to one another and one of which is coupled to the rotatable operating part. The second brake component, acting as an outer brake component, surrounds the first brake component that acts as an inner brake component. A closed magnetorheological brake chamber is provided with a magnetorheological medium and is formed between the two brake components and has a peripheral braking gap.

A method for operating an input device and an input device having an input element of the input device that is manually actuated for carrying out an input. A movability of the input element can be selectively delayed, stopped, blocked and enabled by means of a controllable magneto-rheological braking device. The mobility of the input element is adjusted in a targeted manner as a function of at least one input condition stored in the computer device. The input condition can have a movement parameter of the movement of the input element, which in turn comprises at least the direction, the speed and/or the acceleration of a movement.

A method and apparatus for an automobile's magneto-rheological brake (MRB) are disclosed which include: a shaft connected to a stationary housing, a magneto-rheological fluid chamber positioned inside the stationary housing, a rotary disc connected to and rotate with the shaft, a plurality of magnetic coils wound directly onto a lateral side of the MRB chamber.

In one aspect, there is provided a damper control system for a reciprocating pump assembly according to which control signals are sent to electromagnets. In another aspect, there is provided a method of dampening vibrations in a pump drivetrain according to which a beginning of torque variation is detected and at least a portion of the torque variation is negated. In another aspect, signals or data associated with pump characteristics are received from sensors, torque characteristics and damper response voltages per degree of crank angle are calculated, and control signals are sent to electromagnets. In another aspect, a damper system includes a fluid chamber configured to receive a magnetorheological fluid; a flywheel disposed at least partially within the fluid chamber and adapted to be operably coupled to a fluid pump crankshaft; and a magnetic device proximate the flywheel. The magnetic device applies a variable drag force to the flywheel.

A hydraulic fluid system is disclosed and that utilizes a hydraulic motor or gear pump and a magneto-rheological fluid (MRF) brake that is interconnected with an output of the hydraulic motor. The MRF brake may utilize a rotatable rotor that is disposed within a magneto-rheological fluid and that is interconnected with an output (e.g., a rotatable output shaft) of the hydraulic motor. An electrical control signal may be provided to the MRF brake (e.g., to a magnetic coil) to adjust the viscosity of the magneto-rheological fluid, and thereby a braking torque exerted on the output of the hydraulic motor.