How to determine which component inside the WB miniature cycloidal reducer is causing abnormal output speed

1. Non-Dismantling Preliminary Judgment (Quickly Narrow Down Fault Scope)

No disassembly required, quickly identify faulty components through operational status and simple operations

1. Input shaft flat key/ spline failure: The motor runs idle while the reducer input shaft does not rotate synchronously, with noticeable idle clearance on the input side, resulting in directly lower speed or complete output failure.

2. Swivel bearing/eccentric bushing failure: When manually rotating the input shaft, the resistance fluctuates between high and low, accompanied by periodic "clicking" noises, while the output speed still exhibits noticeable fluctuations under no-load conditions.

3. Output mechanism (pin/insert) wear: When rotating the output shaft in both directions, the backlash exceeds 0.2mm, resulting in noticeable idle rotation during direction reversal and a sudden drop in speed under load.

4. Abnormal cycloid gear/needle gear meshing pair: A uniform "rustling" friction noise occurs during operation, with input current fluctuation exceeding the rated value by 5% and localized rapid temperature rise in the housing.

2. Oil Auxiliary Positioning (Locking Wear Type)

Extract internal lubricating oil to observe impurity morphology and accurately identify faulty components:

1. The oil contains uniformly fine metal particles: normal wear of the cycloidal gear or pinion sleeve, with gradually increasing meshing clearance leading to a drop in rotational speed.

2. Presence of chunky metal debris in the oil: Bearing cage fracture, cycloidal gear tooth breakage, or needle pin breakage can directly cause speed jamming or even interruption.

3. The oil turns black, becomes viscous, and shows no obvious metal debris: This indicates dry grease or severe oil shortage, leading to a sharp increase in operating resistance and significantly reduced speed under load.

3. Precision Verification After Disassembly (Component-Level Diagnosis)

After opening the casing, inspect the core components one by one according to priority, following the corresponding exclusive judgment criteria:

1. Cycloidal gear: Tooth surface wear > 0.1mm, pitting area exceeding 1/3, chipped teeth/cracks, or phase misalignment between paired cycloidal gears, directly disrupting the meshing speed ratio and causing abnormal rotation.

2. Pin tooth pin/pin tooth sleeve: The inner wall of the pin tooth sleeve wears grooves, the pin tooth pin becomes loose, falls off, or breaks, causing slippage during meshing and severe speed fluctuations or even complete stalling.

3. Transfer arm bearing: The inner and outer raceways have pitting and ball spalling, the bearing clearance exceeds the standard, and the eccentric bushing rotates out of sync, directly disrupting the rotation rhythm of the cycloidal gear, causing fluctuating speeds.

4. Output pin and sleeve: The clearance between the pin and sleeve exceeds 0.2mm, resulting in delayed power transmission and slippage, with the output speed continuously decreasing as the load increases.

5. Pinion Housing: Pinion bore wear exceeds 0.03mm, bore spacing error exceeds 0.06mm, pinion positioning offset, meshing backlash uniformity completely fails, rotation speed consistently low with abnormal noise.