RV transmission is a newly emerging kind of transmission, which is developed on the basis of traditional needle-pendulum planetary transmission, not only overcoming the shortcomings of the general needle-pendulum transmission, but also because of a series of advantages, such as small size, light weight, wide range of ratios, long service life, accuracy and stability, high efficiency, smooth transmission, etc. Increasingly, it has received wide attention at home and abroad. RV reducer is composed of cycloid pinwheel and planetary bracket with its small size, strong impact resistance, high torque, high positioning accuracy, low vibration, large reduction ratio and many other advantages are widely used in industrial robots, machine tools, medical testing equipment, satellite receiving systems and other fields. It is more commonly used in robotics harmonic drive has much higher fatigue strength, stiffness and life, and the return precision is stable, unlike the harmonic drive as with the use of time growth of the movement accuracy will be significantly reduced, so many countries around the world high-precision robot drive more RV reducer, therefore, this kind of RV reducer in the advanced robot drive gradually replace the harmonic reducer of the development trend.
Principle of operation
The RV-E reducer is a 2-stage reduction type.
The first reduction stage...Spur Gear Reduction Mechanism
The rotation of the input shaft is transmitted from the input gear to the spur gear, which reduces the gear in accordance with the ratio of the number of teeth. This is the first reduction section.
2nd reduction section...Differential gear reduction mechanism
The spur gear is connected to the crankshaft and becomes the input of the second reduction section. At the eccentric portion of the crankshaft, the RV gear is mounted through a rolling bearing. In addition, needle teeth, which are only one more than the number of RV gears on the inside of the housing, are arranged in equal tooth spacing.
If the fixed housing rotates the spur gear, the RV gear also performs eccentric motion due to the eccentric motion of the crankshaft.
At this point, if the crankshaft rotates one week, the RV gear rotates one tooth in the opposite direction from the crankshaft.
This rotation is output to the shaft of the 2nd reduction section.
When the shaft is fixed, the housing side becomes the output side.
There are many ways to use the RV-E type reducer. The direction of rotation and speed are shown in the following figure.
Please select the best practical method.
The reduction ratio i obtained by adding the 1st reduction section and the 2nd reduction section varies depending on the method of use, and can be calculated from the speed ratio value shown in the following formula.
Shaft rotation
R :Speed ratio value
Z1:Number of teeth of the input gear
Z2:Number of teeth of the spur gear
Z3:Number of teeth of the RV gear
Z4:Number of pinion roots i:Reduction ratio