6.2. Trouble Symptoms and Possible Causes

6.2. Trouble Symptoms and Possible Causes

 

As shown in [Table 6-1], there may be many parts as the cause of one phenomenon.

Refer to next page to determine which part is malfunction.

 

Table 6‑1 Trouble phenomenon and cause

Defect parts   Trouble phenomenon	Reducer	Brake	Motor	Encoder	Backlash	Grease
Overload         [Note 1]	○	○	○
Displacement	○		○	○
Abnormal sound occurrence	○	○	○			○ [Note 5]
Noise in operation [Note 2]			○		○
Staggering at stop [Note 3]			○	○
Irregular twitching [Note 4]			○	○
Abnormal deviation			○	○
Free fall of an axis	○	○
Overheating	○	○	○	○		○
Incorrect action and out of control movement			○	○

 

[Note 1] Overload ----------------- Phenomenon occurring when a load exceeds the rated motor load.

In specific, thermal relay of circuit protector is tripped.

[Note 2] Noise in operation ----- Phenomenon which occurs vibration on operation.

[Note 3] Staggering at stop ----- Phenomenon which gives oscillating motion when the robot stops

[Note 4] Irregular twitching ----- Phenomenon which gives sporadic twitching when the robot is not in motion.

[Note 5] If there is noise from the greased part of reducer at reduced-speed operation, check the state closely for 1-2 days during operation. Generally, the noise will go away.

(The noise will go away if you run the axis at a high speed for 5-10 minutes).

 

The noise may be caused by following reasons.

1.      Operation after greasing or replacing the reducer

2.      Operation after long-term storage

3.      Operation at a low speed

4.     Operation at a low temperature

5.      When using unspecified grease

6.      When mixing greases with different specifications