The Hense Rotary Actuator

What is a hydraulic rotary actuator?

The hydraulic rotary actuator belongs to the group of hydraulic motors and is a special design. Like conventional hydraulic motors, it converts hydraulic energy (pressure x volume) into rotary mechanical energy, but the movement of the drive shaft is limited in comparison to the hydraulic motor at the rotation angle. The drive shaft of a pivoting motor always leads to a limited reciprocal rotary motion with a break in the reversing point. Pivoting motors suits for the realization of pivoting movements and rotational movements with a limited rotation angle.

The switching symbol according to DIN ISO 1219 T1 for a slewing motor is shown.


Rigid Vane Rotary Actuators

The Hense rotary actuator is designed according to the principle of the Rigid Vane Rotary Actuators and is integrated into the group of rotary piston machines which is characterized by the absence of a deflection, friction and play-bearing deflection mechanism. The circular ring-shaped interior of the drive is divided by circular ring segments into at least two working chambers, and the inflowing pressure medium generates a direct pivoting movement of the drive shaft without further mechanical transmissions. This predestines the Hense oscillating motor for high load figures and for integration into a control circuit with highly dynamic movements and exact positioning.

Due to the design, swivel angles of up to 310 ° can be achieved. The achievable torque is determined by several variables, e.g. Housing diameter, housing length, number of working chambers and operating pressure, and therefore this design is very variable with regard to the optimum utilization of an available installation space. Due to the high power density, torques of up to 330000 Nm are possible.


Rotary Actuators with helical gearing

Due to its design, as well as the curved-roller, ball-screw and rack-and-pinion motor, the Helac Rotary Actuators with helical gearing is placed in the group of pushing-piston machines with deflection mechanism.

In this case, the drive uses as a deflection mechanism a screw gear for converting the linear movement into a pivoting movement. For this purpose, the cylindrical interior of the drive is divided into two working chambers by a piston, comparable to a hydraulic cylinder. The piston is provided on the outside- and inside-diameter with two counter-rotating threads without self-locking, which in turn are engaged with the housing and the drive shaft.

Due to the design, rotary angles of 360° can be achieved. The torque achievable in the series of up to 83,600 Nm is determined by sizes, for example Housing diameter, thread pitch and operating pressure. The holding torque can be a multiple of the output torque.