Novel rotary magnetorheological brake

The invention discloses a novel magnetorheological rotary damper. A novel rotary magnetorheological brake is mainly composed of a left end cover, a brake inner cylinder, excitation coils, a damper outer cylinder, a coil carrier iron core, a spiral piston rod, a right end cover, a right bearing and the like. A power supply generates a magnetic field through energizing of the excitation coils, a magnetorheological fluid spirally moves in damping gaps under the pushing action of the spiral piston rod, moreover, the magnetorheological effect is generated under the action of the magnetic field, sothat the shear stress of the magnetorheological fluid is increased, a relatively large rotating torque is generated, and the rotation of the spiral piston rod is hindered. According to the brake, thespiral piston rod is adopted to change the flow mode of the magnetorheological fluid so that the braking torque can be increased by increasing the contact area under the condition that the use amountof the magnetorheological f