Wave transmission with intermediate links calculation of gear ratio, mechanical gear with intermediate rolling elements, the principle of operation advantages and disadvantages

Wave transmission provides a high reduction ratio, high efficiency, compactness, long service life etc.



Wave transmission with intermediate links (ITPS) has a large transmission ratios, high life, high efficiency and ensures the transmission of high torques with small dimensions, smooth and quiet operation.



Diagram and working principle


Wave transmission is used



Highly efficient power transmission mechanisms on the basis of wave gear with intermediate links (VPPS) have a qualitatively new resource and power characteristics superior to known analogs.

Wave transmission with intermediate links (ITPS) has a large transmission ratios, high life, high efficiency and ensures the transmission of high torques with small dimensions, smooth and quiet operation.

In comparison with the planetary gears, the gain in weight can be 1.5–2 times.

Low weight and compact shape is important in many fields such as robotics and aviation. A small gap is very important in accurate Electromechanical systems such as servo – manipulators, robots or positioning systems.

The main design feature of this transmission is the classical wave diagram of rolling elements (balls or rollers) instead of the flexible element.


Diagram and working principle:

The program consists of four major elements: a drive shaft with an eccentric 1, separator 2, rolling elements 3 and of the crown of Cam sectors 4.

The eccentric shaft 1 rotates, causes a radial displacement of the rolling element 3 in the slots of the separator 2. Creates the effect of “waves” running through the chain separated rolling elements, i.e. the chain is analogous to the flexible element in classical wave circuits. The rolling elements are in contact with the working surfaces of the crown Cam sectors 4, causing its rotation. Each full turn of the eccentric shaft turns the crown on one of the Cam sector. Thus, the gear ratio is determined by the number of Cam sectors. The transmission mechanism is a differential.



– high gear ratio. The range of gear ratios of the gearboxes VPS:

– single-stage – 9÷60;

– differential – up to 1000;

– two-stage – to 3500;

– multi – over 1000 000;

– high torque on the output link, the large overload reserves and high rigidity of the kinematic links. The design VPS the load is transmitted via balls or rollers with the angle from π/2 to π. That is, when a reduction ratio in one stage is 50, in engagement at the same time is up to 25 rolling elements, which allows to transmit torque to 5-10 times greater relative to the gears, with multiple short-term overload and practically without elastic deformation, with equal weight and size indicators;

– compactness. Compared with the gear, with equal gear ratios and torque VPPs smaller in size 2-6 times depending on the size;

– high efficiency. Is 0.8–0.9, is in special design of the transmission efficiency is 0.97;

– small moment of inertia, a high level of dynamism. The design ITPS with a high speed rotates the shaft eccentric generator which has a negligible mass and diameter. Therefore, the total mass moment of inertia of the moving parts is small and comparable with the moment of inertia of the electric motor. This allows for quick start and braking of gears and dynamic reverse rotation;

– small angular clearance. Due to the large stiffness of the kinematic links VPPs at rated load, the total angular clearance (backlash) is, grad: very accurate – up to 0.05; high precision – up to 0.12; normal accuracy – to 0.8;

– small vibration. The design of the reducers ITPS consists of wave modules are offset to each other on π or 2π/3, which ensures absolute balancing of the masses reduces the influence of errors of manufacturing and installation;

– increase speed. Wave transmission with intermediate links allows you to create multipliers with a high value of efficiency (in special design to 0.97), significantly expanding its scope;

– high reliability and long service life.


Wave transmission is used:

– in robotics, machine tools and aircraft.