H2W Technologies has developed several high torque rotary voice coil actuators, otherwise known as a limited angle torque motors or LATs. The model TWR-034-800-1RC was designed to allow for a relatively low moving mass and inertia, as well as a long rotary stroke of 34 degrees [0.59 radians] on a 11.4” [290 mm] arm, which equates to a travel of 6.75 inches [171.5 mm] which is long travel for this style of actuator, which typically restrained to an equivalent linear travel of 2 inches [50.8 mm]. This rotary voice coil actuator can generate a continuous torque of 1400 in-oz [9.8 N-m] and a peak torque of 4200 in-oz [29 N-m] at a duty cycle of 10% (i.e. 1 second on, and 9 seconds off) in each coil on a 11.4 inch [290 mm] rotation arm.
The TWR-034-800-1RC has a total angular displacement of 34 degrees [0.59 radians] and a motor constant of 275 in-oz/sqrt(watt) [1.92 N-m/sqrt(watt)]. The voice coil motor requires 1.7 amps of continuous current per coil and 5.1 amps of peak current per coil to generate the specified forces. The actuator fits in and envelope of 10.26 in [260.5 mm] x 3.01 in [76.4 mm] x 3.39 in [86 mm].
The moving coil design ensures a hysteresis free movement as the coil is wet wound and self-supported, and the non-commutated coil allows for ripple-free motion and no cogging. The voice coil actuator has been designed with mounting provisions in the magnet and coil assemblies. This allows for the integration of a bearing system to maintain the clearances between the coil and permanent magnetic field assemblies. The rotary voice coil actuator is ideal for applications requiring high torque and high-speed applications. Examples of such applications are driving a gimbal axis in scanning applications as well as providing stabilizing torques for image stabilization. More examples of our rotary voice coils can be found here.