There are provided a magnetic viscous fluid containing magnetic particles, a carrier fluid, and an organic molybdenum compound, in which a content of the magnetic particles is 35% by volume or more and 50% by volume or less with respect to a volume of the magnetic viscous fluid, a viscosity of the carrier fluid, which is measured with an electromagnetic rotary viscometer at a measurement temperature of 25° C., is 10 mPa.Math.sec or more, and a shear viscosity of the magnetic viscous fluid, which is measured at a shear rate of 1,000 sec.sup.-1 at a measurement temperature of 25° C., is 500 mPa.Math.sec or less, as well as a magnetic viscous fluid device including the magnetic viscous fluid and a production method for the magnetic viscous fluid.

A speed retarding device for a rotary nozzle includes a hollow cylindrical housing and a rotatable tubular shaft rotatably carried by the housing. The shaft has a central axial bore and an enlarged drag sleeve portion carried in the housing. A pair of support bearings support the drag sleeve portion of the shaft in the housing. An annular inner seal between each of the support bearings and the drag sleeve portion defines a cavity within the housing receiving a viscous fluid confined within the cavity. The drag sleeve portion includes a peripheral helical groove and a plurality of axial bores extending therethrough parallel to the central bore, one or more blind axial bores each having a closed end an open end, and a piston disposed in each of the one or more blind axial bores each defining an air space between the closed end and the piston.

A speed retarding device for a rotary nozzle includes a hollow cylindrical housing and a rotatable tubular shaft rotatably carried by the housing. The shaft has a central axial bore and an enlarged drag sleeve portion carried in the housing. A pair of support bearings support the drag sleeve portion of the shaft in the housing. An annular inner seal between each of the support bearings and the drag sleeve portion defines a cavity within the housing receiving a viscous fluid confined within the cavity. The drag sleeve portion includes a peripheral helical groove and a plurality of axial bores extending therethrough parallel to the central bore, one or more blind axial bores each having a closed end an open end, and a piston disposed in each of the one or more blind axial bores each defining an air space between the closed end and the piston.

A device component has a magnetorheological braking apparatus with a stationary holder and at least two brake components. One of the two brake components is connected to the holder for conjoint rotation and extends in the axial direction. The two brake components can be rotated relative to each other. The second brake component has a hollow sleeve part and surrounds the first brake component. A closed chamber is formed between the brake components. The second brake component is rotatably accommodated on the first brake component at a first end of the closed chamber. The closed chamber is substantially filled with a magnetorheological medium. A magnetic-field generator forms a magnetic field to influence the medium in the closed chamber. The second brake component is axially slidable on the first brake component to change a volume of the closed chamber to compensate for temperature-related and/or leakage-related volume changes.

A method for operating an input device. An input element of the input device is manually operated to perform an input into a computer device operatively connected to the input device. Mobility of the input element can be selectively delayed, blocked, and enabled by a controllable magneto-rheological braking device. The mobility of the input element is selectively adjusted by the computer device at least as a function of at least one input condition stored in the computer device. The input device may be a computer mouse.

A torque generation apparatus includes a magnetic disc rotatable about a rotation axis, a first yoke, a second yoke, a magnetic viscous fluid placed between the magnetic disc and the first yoke and the second yoke, a coil, and a third yoke. The coil overlaps with the magnetic disc as viewed along the rotation axis. The third yoke constitutes a magnetic path of a magnetic field generated by the coil together with the first yoke and the second yoke. The magnetic disc includes a torque increasing portion at at least one of a surface facing the first yoke and a surface facing the second yoke. The torque increasing portion is provided in an outer circumferential area of the magnetic disc in a radial direction and causes a shearing force to a cluster of the magnetic viscous fluid to become larger than that in the inner circumferential area.

A magnetorheological brake device for adjusting operating states by way of rotational movements includes an axle unit and a rotary body that can be rotated relative to the axle unit. A torque for the rotation of the rotary body can be varied in a targeted manner by a magnetorheological brake. A sensor device functions to detect a rotational position of the rotary body and includes a magnet ring unit and a magnet field sensor rotationally fixed to the axle unit and arranged radially and/or axially next to the magnet ring unit. The magnet field sensor is also arranged at least partially within the axle unit.

The invention relates to a rotary control device for a vehicle comprising a user interface surface, in particular a knob, that is embodied to rotate with respect to a housing of the device around a rotational axis of the device, further comprising a sensor unit for monitoring the orientation and/or rotational movement of the user interface surface with respect to the housing, a processing unit, and a communications interface for transmitting control signals according to an output from the processing unit, said output being generated by the processing unit on the basis of sensor data from the sensor unit.

An electronic control unit (ECU) is disclosed. The ECU may detect an emergency stopping event associated with a vehicle. The ECU may determine, based on detecting the emergency stopping event, that electro-hydraulic brakes of the vehicle are in a disabled mode. The ECU may determine, based on determining that the electro-hydraulic brakes are in the disabled mode, a position of a brake pedal of the vehicle. The ECU may override, based on the position of the brake pedal, the disabled mode to engage the electro-hydraulic brakes during the emergency stopping event.

A magnetorheological braking device with a fixed mount and with two braking components. One of the two braking components is non-rotatably affixed to the mount and the two braking components are continuously rotatable relative to one another. A first braking component extends in the axial direction. The second braking component has a hollow shell part that extends around the first braking component. A peripheral gap is filled with a magnetorheological medium. The first braking component has an electric coil and a core made from a magnetically conductive material. Magnetic field concentrators on the core and/or magnetic field concentrators on the shell part protrude into the gap, which results in a peripheral gap with a variable gap height. A magnetic field of the electric coil runs through the core and the magnetic field concentrators and through the gap into a wall of the shell part.