How to Determine Whether the Output Speed of WB Miniature Cycloidal Reducer is Abnormal

1、 Core Quantitative Judgment Criteria

1. Theoretical speed calculation: First confirm the rated input speed of the motor (1450rpm for conventional three-phase asynchronous motors), and calculate the theoretical output speed based on the reduction ratio indicated on the reducer nameplate:

2. Theoretical output speed=Motor input speed ÷ Rated reduction ratio of gearbox

3. Actual deviation determination: Use a contact/photoelectric tachometer to directly measure the speed of the output shaft during stable operation. If the actual speed deviates from the theoretical value by more than ± 3%, it can be determined as abnormal speed. Common manifestations include significantly low speed, periodic fluctuations, sudden drops in speed after loading, or even no output speed.

2、 Quick dimension inspection without disassembly

1. External connection inspection: Disconnect the output end load coupling and manually rotate the output shaft. If there is uneven rotational resistance and a sense of jamming when unloaded, after ruling out the load side fault, it is highly likely that the speed problem is caused by abnormal internal transmission of the reducer; At the same time, check whether the flat key between the motor and the input shaft of the reducer is loose, and whether the keyway is deformed and slipping. Failure of such connections will directly lead to loss of speed.

2. Operation status verification: Run without load for 30 minutes, use a vibration meter to detect the radial vibration of the output shaft. If the vibration acceleration is greater than 1.5mm/s and accompanied by periodic abnormal noise, or if the temperature rise of the output shaft bearing exceeds 40 ℃, it will be accompanied by abnormal performance such as speed fluctuations and sudden increases in operating resistance.

3. Load matching verification: If the speed after being loaded is significantly lower than the measured value under no-load, and the motor current exceeds 1.2 times the rated current, it indicates that the actual load far exceeds the adaptation range of the gearbox. Overload causes torque attenuation, ultimately leading to abnormally low output speed.

3、 Depth of disassembly confirmation dimension

1. Mesh clearance verification: After disassembly, use a feeler gauge to measure the mesh clearance between the cycloid gear and the needle gear sleeve. The standard mesh clearance of the WB series micro cycloid reducer is 0.02~0.05mm. If the clearance exceeds 0.2mm, it indicates severe wear of the components and may cause transmission slippage and significant speed fluctuations.

2. Lubricating oil status verification: Observe whether the lubricating oil is black, turbid, contains metal debris, and if the concentration of iron element in the oil suddenly increases, it indicates that the cycloidal gear, needle pin or bearing has undergone severe wear, which will directly damage the transmission accuracy and cause abnormal speed.

3. Shaft component inspection: Use a dial gauge to detect the axial runout of the output shaft. If the runout exceeds 0.15mm, it indicates that the bearing clearance of the output shaft exceeds the standard or the positioning component has failed. Eccentricity of the shaft system operation can cause unstable speed transmission.