RV Reducer VS Harmonic Reducer

Nowadays, RV reducers and harmonic reducers are widely used in the robot industry. Which one is better? Let's see.

RV reducer principle

RV reducer is a high-precision control reducer with a cycloidal pin wheel reduction structure. Due to the large number of gears engaged at the same time, the reducer has the characteristics of small size, lightweight, high rigidity, and overload resistance. In addition, due to the small backlash, rotary vibration, and inertia, it has good acceleration performance and can achieve smooth operation and obtain the accuracy of the correct position.

Principle Of Harmonic Reducer

When harmonic is used as a reducer, usually in the form of an active wave generator, fixed circular spline, and flex spline output.

When the wave generator is installed into the inner circle of the flex spline, it forces the flex spline to produce elastic deformation and to become elliptical, so those flex spline teeth at the long axis are inserted into the gear groove of the circular spline, which becomes a full engagement state; while at the short axis, the gear teeth of both flex spline and circular spline are completely untouched and in a separation state. The process between engagement and separation is in the state of meshing in or meshing out. When the wave generator rotates continuously, it forces the flex spline to deform, which makes the teeth of the two splines change their working state during the process of meshing in, engagement, meshing out, and separation, resulting in the so-called staggering teeth movement, thus realizing the movement transmission between wave generator and flex spline.

RV reducer advantages:

Strong impact resistance, large torque, high positioning accuracy, high rigid, small vibration, and large reduction ratio.

Harmonic Reducer advantages:

High accuracy; large transmission ratio; high bearing capacity; small volume and light weight; high transmission efficiency and long service life; stable transmission; no impact and low noise.

RV reducer application:

Pipe bending machine, gantry machining center, positioning machine, industrial robot.

Harmonic drive application:

Collaborative robot, multi-axis robot, SCARA, machine tools, medical equipment, AGV.

In conclusion, because of different principles and advantages, harmonic reducer and RV reducer have different applications and can’t replace each other.