LZ9025 Hollow-Shaft Planetary Joint Reducer

The core technology of the product lies in the harmonic integrated joint module, featuring a drive-control integrated design. The inner rotor structure enables hollow cabling, while diversified model options including 11, 14, 17, 20, 25, 32 and 40 series ensure flexible applications. With a compact and miniaturized profile and low power consumption, it adopts a pin-type brake mechanism that triggers mechanical locking instantly upon power loss, with an action time of less than 10ms.

The dual steel wheel design, integrating cross-roller bearings with steel wheels, reduces axial space occupation. By meshing two steel wheels with one flexspline, it mitigates stress from flexspline deformation, achieving smooth operation, high efficiency and positioning accuracy up to 20 arcseconds.

Structural and Dimensional Design Features

Overall Specifications: High Torque, Slim Design

Outer diameter:Maximum outer circle Ø85mm, larger than the Ø70mm of LZFT64, corresponding to a higher torque-carrying capacity.

Axial length:Total thickness approximately 35.5 mm (including flange), making this a compact joint reducer suitable for applications with tight joint space constraints.

The output-end flange outer diameter is Ø78 ±0.1 mm, with a positioning reference of Ø85g6 and tolerances ranging from (-0.034 to -0.012). It achieves IT6 precision, ensuring coaxial alignment during load installation.

High-precision Interface, Optimized Specifically For Joint Modules

Center hole:Input side Ø11 (tolerance +0.018/0), output side Ø20H6 (+0.013/0); both feature IT6/IT7 accuracy grades and support wire-through encoders as well as hollow-shaft wiring designs.

Mounting hole positions:

• Output side: 8 evenly spaced M4 holes, 3 Ø4H7 positioning holes, and 4 Ø4h6 locating pin holes, which can simultaneously meet both load mounting and positioning reference requirements.

• Input side: 4-M4 through-holes and 2-Ø5H7 positioning holes provide high-precision alignment for motor installation.

Critical dimension tolerance control:

• Outer cylindrical positioning: Ø85g6, ensuring precise fit with the joint housing.

• Center-hole coaxiality: Using the center holes at the input and output ends as reference points, ensure the coaxial alignment of the motor, gearbox, and load, thereby reducing vibration and noise.

Force and Rigidity Design

Maximum radial force: 500 N; maximum axial force: 300 N. It can withstand eccentric loads and axial impacts on the joint, and its structural rigidity meets the requirements of medium-load exoskeletons and collaborative joints.

2-stage planetary gear structure with a rational torque distribution, strong output flange rigidity, and resistance to deformation.

Joint Module Adaptability Highlights

Dual-encoder-friendly design

The center features a hollow structure, supporting a dual-encoder layout on both the motor side and the output side, with no cable interference.

The positioning holes (Ø4H7/Ø4h6) on the output-side flange can directly serve as the reference for mounting the encoder magnet, ensuring accurate angular detection.

Standardized installation interface

The motor mounting hole positions and output flange dimensions are both standard specifications commonly used in robotic joint modules, allowing direct compatibility with mainstream brushless motors and load-end structures available on the market, thereby reducing customization costs.

The short axial length significantly reduces the overall length of the joint module, optimizing the workspace for robotic arms and exoskeletons.

Operational Condition Adaptability

Operating temperature: -20°Cto 90°C, covering all scenarios from low-temperature outdoor environments to high-load thermal conditions.

Noise ≤ 65 dB(A), suitable for human-machine collaboration, exoskeletons, and other noise-sensitive applications.

Lifetime lubrication design, maintenance-free, suitable for mass-produced joint modules.