RV Cycloidal Pinwheel Reducer

RV Cycloidal Pinwheel Reducer is a high-precision reduction device based on the principle of cycloidal pinwheel meshing. It achieves large reduction ratio (30:1~300:1) power transmission through a two-stage reduction structure (planetary gear+cycloidal pinwheel) and is the core transmission component of industrial robot joints.

The working principle of RV Cycloidal Pinwheel Reducer can be summarized as follows: the input shaft is initially reduced and drives the eccentric crankshaft through a planetary gear mechanism. The crankshaft drives the cycloidal gear to perform eccentric motion, and the cycloidal gear meshes with the fixed needle teeth to produce reverse rotation. Finally, the output disk extracts the self transfer motion and outputs a large torque. This combination of "planetary deceleration+cycloidal meshing" combines high precision, high rigidity, and high transmission efficiency, making it the core transmission component of high-end equipment such as industrial robots and precision machine tools.

Here In this page, we introduce SE serial RV Reducers from TallMan Robotics, which is the top leading manufacturer of RV Gearboxes, you will see data sheet, production pictures,videos as follows:

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Working principle of RV Cycloidal Pinwheel reducer is based on the collaborative effect of two-stage reduction mechanism, which achieves high-precision and high torque power transmission through the combination of planetary gear reduction and cycloidal pinwheel reduction. Its core is to convert high-speed input motion into low-speed, high torque output, while using a unique structural design to counteract the vibration caused by eccentric motion, ensuring operational stability. The following is its detailed working principle:

1. First stage: Initial deceleration of planetary gears

1).Power is transmitted from the input shaft, and the gear (sun gear) at the end of the input shaft meshes with multiple planetary gears.

2).When the sun gear rotates, it drives the planetary gears to revolve around the sun gear, while the planetary gears themselves also rotate on their own. 3).The orbital motion of the planetary gear is transmitted to the crankshaft (eccentric shaft) rigidly connected to the planetary carrier through the planetary carrier. At this time, the crankshaft rotates together with the planetary carrier to complete the first stage of reduction (the reduction ratio is usually 3~5:1).

Note: The crankshaft is a key component connecting two stages of deceleration, and its shaft section is designed as an eccentric structure (usually with two eccentric parts with a phase difference of 180 °), used to drive the cycloid wheel to perform eccentric motion.

2. Second stage: Cycloid pinwheel main reduction (core reduction link)

1).Eccentric motion of cycloid gear: The eccentric part of the crankshaft is fitted with cycloid gears (usually two, with a phase difference of 180 °). When the crankshaft rotates, the cycloid gears perform a planar eccentric motion under eccentric drive (i.e., a "revolution" trend), but due to the meshing restriction between the cycloid gears and the needle gear housing, they cannot freely revolve.

2).The needle tooth shell is a fixed component, with a circle of needle teeth (cylindrical rollers) evenly distributed on the inner wall. The tooth profile of the cycloidal gear meshes with the needle teeth, forming a closed transmission pair.

3).Rotation output of cycloid gear: During eccentric motion, the cycloid gear rotates in the opposite direction by a certain angle (opposite to the direction of rotation of the crankshaft) for each revolution (eccentric period driven by the crankshaft) due to its meshing relationship with the needle teeth.

4).The number of teeth on the cycloid gear is one less than the number of needle teeth (for example, 11 needle teeth and 10 cycloid gears), so for every revolution of the crankshaft, the cycloid gear rotates only one tooth in the opposite direction, achieving a significant reduction in speed (the second stage reduction ratio is usually 10~11:1).

5).Motion integration and output: The rotational motion of the cycloid wheel is transmitted to the load through the output disc. The output disc is connected to the cycloid wheel through a pin shaft or bearing to counteract the eccentric revolution of the cycloid wheel, extract only its rotational motion, and ultimately output low-speed, high torque power through the output flange.

RV Cycloidal Pinwheel Reducer has become the core transmission component of high-end intelligent manufacturing due to its high rigidity (stiffness coefficient three times that of traditional planetary reducers) and error equalization effect (accuracy retention improved by 50%) brought by multi tooth meshing. Currently, the fatigue life of domestically produced products under heavy load conditions (>3000Nm) is still 15-20% lower than similar products from Nabotesk. However, through material modification (such as adding rare earth elements) and process innovation (laser assisted assembly), it is expected that complete import substitution can be achieved by 2025. The combination of magneto rheological damping technology in the future will further enhance its performance in high dynamic scenarios.