Development of a cartridge-mounted 2D electro-hydraulic piston with dual sensitive chambers based on a claw-pole torque motor

In this paper, a cartridge-mounted dual-sensitive chamber 2D electrohydraulic piston based on claw pole torque motor (CPTM) is proposed. It converts the torque and angular displacement of the torque motor into force and displacement by means of a servo screw mechanism and outputs them outward using the piston. As an electro-mechanical converter, it can not only take advantage of the exceptional power density of hydraulics, but also realize open-loop proportional control. This electro-hydraulic piston is first described in terms of its structure and operating principle. Secondly, the equations of motion of the CPTM were deduced, and the expression of the output angle displacement was obtained. And the influence of the height of the claw pole teeth on the output angle displacement as well as the proportional characteristics of the CPTM is analyzed based on finite element simulation. Finally, the steady state hydrodynamic force as well as the output force and linear displacemen t of the electro-hydraulic piston with double sensitive cavities were analyzed. According to the results, the steady-state hydrodynamic force of the two-dimensional electro-hydraulic piston with double sensitive cavities is zero, and the output force is twice as much as that of the two-dimensional electro-hydraulic piston with single sensitive cavities. The output angle displacement of the CPTM is positively correlated with the height of the CP tooth, and the output angle displacement is proportional to the input magnetomotive force when the height of the CP tooth is 7.75 mm. Two-dimensional electro-hydraulic piston output linear displacement is proportional to CPTM input angular displacement.