Magnetorheological fluid brake and control method therefor
View Patent ↗A magnetorheological fluid brake and a control method therefor. When braking is not required, the brake does not work, and no field coils are energized. When braking is required and the brake receives a retarding braking signal, a field coil module is energized, the current is gradually increased, an oil port is gradually closed, and a back pressure inside the brake is also gradually increased, thereby gradually increasing a braking force so as to achieve a braking effect. By using the characteristics of a pump and the characteristics of a valve for the magnetorheological fluid, the viscosity of the magnetorheological fluid is adjusted, such that a back pressure is generated in a pump body, which in turn imposes a braking torque on a shaft, thereby performing braking.
1. A magnetorheological fluid brake, comprising
a main housing ( 8 ),
an inner rotor ( 15 ),
an outer rotor ( 14 ),
a side housing ( 4 ),
a heat exchanger,
a sealing portion and
a distribution passage, the outer rotor ( 14 ) and the inner rotor ( 15 ) being arranged in sequence in the main housing ( 8 ), and a shaft ( 1 ) passing through the inner rotor ( 15 ); the side housing ( 4 ) being arranged on one side of the main housing ( 8 ), and the distribution passage being arranged inside the side housing ( 4 ); the heat exchanger ( 9 ) being arranged on an other side of the main housing ( 8 ), wherein
the distribution passage comprises a high-pressure oil channel ( 21 ) and a low-pressure oil channel ( 5 ); an oil filling port ( 7 ) is in communication with the high-pressure oil channel ( 21 ), and the low-pressure oil channel ( 5 ) is in communication with an oil discharge port ( 6 ); the high-pressure oil channel ( 21 ) is provided with a high-pressure oil port ( 28 ), and the low-pressure oil channel ( 5 ) is provided with a low-pressure oil port ( 26 ); the high-pressure oil port ( 28 ) and the low-pressure oil port ( 26 ) are in communication with each other through a flow-through channel; a first field coil module ( 27 ) is provided in the high-pressure oil port ( 28 ), a second field coil module ( 29 ) is provided in the low-pressure oil port ( 26 ), and a third field coil module ( 30 ) and a fourth field coil module ( 31 ) are provided in the flow-through channel;
a bearing end cover ( 11 ) is connected to the main housing ( 8 ) via a screw ( 12 ), a connecting disc ( 34 ) is connected to the shaft ( 1 ) via a splined connection, wheel fixing bolts ( 35 ) are mounted to the connecting disc ( 34 ), a wheel is connected to the brake via the wheel fixing bolts ( 35 ), and a bolt ( 36 ) is fixed to the shaft ( 1 ) to axially position the connecting disc ( 34 ); and a silicon steel plate ( 38 ) is fixed on a side of the inner rotor and the outer rotor and connected to the main housing ( 8 ) via a countersunk screw.
2. The magnetorheological fluid brake of claim 1 , wherein
the sealing portion comprises a first sealing ring ( 16 ) arranged inside the side housing ( 4 ), a second sealing ring ( 20 ) arranged inside the main housing ( 8 ), and an oil seal ( 2 ) arranged outside the shaft.
3. The magnetorheological fluid brake of claim 1 , further comprising
a first bushing ( 13 ) and a second bushing ( 19 ) arranged outside the shaft.
4. The magnetorheological fluid brake of claim 1 , further comprising
a coolant inlet ( 32 ) and a coolant outlet ( 33 ).
5. The magnetorheological fluid brake of claim 1 , wherein the field coil module comprises a field coil for providing an excitation to a magnetorheological fluid, and further comprises an internal flow channel for the magnetic fluid to pass through.
6. The magnetorheological fluid brake of claim 5 , wherein the internal flow channel is a single-hole flow channel or a multi-hole flow channel.
7. The magnetorheological fluid brake of claim 1 , wherein
a steel plate ( 44 ) is sealed on the side of the inner rotor ( 15 ) and the outer rotor ( 14 ), and the steel plate ( 44 ) is provided with a first via hole ( 39 ) and a second via hole ( 41 ); and the first and second via holes and an oil channel provided in the main housing form a channel for enabling a high-pressure area to communicate with a low-pressure area, and a fifth field coil module ( 40 ) and a sixth field coil module ( 42 ) are arranged on the channel.
8. A magnetorheological fluid retarding control system, having the magnetorheological fluid brake of claim 1 , wherein
the control system further has a brake controller for controlling braking.
9. A method for controlling the magnetorheological fluid brake of claim 1 , wherein
when braking is not required, the brake does not work, no field coils are energized, the shaft ( 1 ) of the brake drives the inner rotor ( 15 ) to rotate, the inner rotor ( 15 ) meshes with the outer rotor ( 14 ) to makes a free rotational motion, and the brake does not generate a retarding braking force;
when braking is required and the brake receives a braking signal, the third field coil module ( 30 ) is energized, the viscosity of the magnetorheological fluid is gradually increased, the damping is gradually increased, and the flow-through channel is blocked to separate a high-pressure area from a low-pressure area; and the first field coil module ( 27 ) is energized, the current is gradually increased, and the high-pressure oil port ( 28 ) is gradually closed, so that a back pressure inside the brake is gradually increased, thereby gradually increasing a braking force so as to achieve a braking effect; and
when a vehicle travels in a reverse direction, the fourth field coil module ( 31 ) is energized, the viscosity of the magnetorheological fluid is gradually increased, the damping is gradually increased, and the flow-through channel is blocked to separate the high-pressure area from the low-pressure area; and the second field coil module ( 29 ) is energized, the current is gradually increased, and the low-pressure oil port ( 26 ) is gradually closed, so that the back pressure inside the brake is gradually increased, thereby gradually increasing a braking force so as to achieve a braking effect.