• Linear motor contain the same components as a rotary motor(magnets & copper coils)
• A linear motor is an uncoiled rotary(servo) motor
• As amperage enters the coils, it creates force that is repelled against the machine
• The motor is also the driving force thus eliminating the need for a ball screw

• Maintains original accuracy for a machine life
• No back lash or lost motion
• Best part geometry & finish reduced skim passes
• Fewer wire breaks
• Increase cutting speed
• No maintenance

• Sodick’s linear motor EDM eliminates the need for ball screws
• The thermostat graph on the right shows the heat
• Expansion of a ball screw under such conditions
• The ball screw, due to friction, can show a temperature increase along its length in less than 30 minutes
• Ball screw wears over the years and need to replace ball screw in 3 – 4 years if maintain original accuracy

Over time, ball screws wear creating scrapped parts; but since linear motor drives is no contact system, they have also eliminated the possibility of scrap parts.

ITEM	Linear motor	Ball screw
Axis control is possible in high speed & high acceleration
No control management delay, quick reactivity
No backlash, high accuracy positioning is possible
With stable profile compensation capability, stable high precision machining
With small energy loss & high efficiency
Simple constructioin, easy assembly and stable performance
No. of parts is small, enabling high cost performance
Contact free, no deformation over years

:Excellent

:Good

:Normal

:Poor