Mitsubishi Electronics IB-1500193(ENG)-D ユーザーズマニュアル

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The response delay (caused by dead band from friction, torsion, expansion/contraction, backlash, etc.) 

caused when the machine advance direction reverses is compensated with the lost motion compensation 

(LMC compensation) function.

With this, the protrusions that occur at the quadrant changeover in the DBB measurement method, or the 

streaks that occur when the quadrant changes during circular cutting can be improved.

DBB: Double Ball Bar

This is an obsolete compensation method. When performing new adjustment, use LMC compensation 

type 3.

In addition to frictional torque influence, this type compensates torsion and expansion/contraction 

influences in the machine system in which compensation amount is changed by travel speed. A 

mechanical system viscosity coefficient setting further enhances the compensation accuracy even if the 

travel speed is changed. Adjustment requires a machine roundness measurement.

This is used in combination with LMC compensation type 3. Compensation is performed by monitoring 

path tracking delay. Therefore, even if the machine friction amount has changed due to aged 

deterioration, the path tracking delay is controlled so that it will be minimum.

1. LMC compensation performs adjustment while measuring the electrical end roundness waveform 

(detector position FB). Disable the NC side machine error compensation (pitch error 

compensation, relative position compensation, backlash compensation).

2. After the compensation adjustment is completed, adjust the machine error compensation while 

measuring the machine error compensation with DBB measurement method, etc.

Compensation 

Cutting 
direction

Circle cutting path after compensation

Circle cutting path before compensation