Improved Cut Quality

One factor which affects the quality of cut, on applications such as plasma and laser cutting, is the variation in distance between the cutting tool head and the material surface.

Most sheet materials deform during cutting producing changes in material surface height as you move across the sheet. When a fixed height cutting head moves over the undulating material surface the separation between cutting tool and surface changes. The result is variable cut quality over the job.

The AMC has been developed to allow it to monitor variation in the distance from the tool head to the material surface and to automatically maintain the optimum cutting height. The result of using the height control unit is a uniform, high quality of cut throughout the entire job.

Stand Alone Height Control Unit or Integral Part of an AMC

The AMC can be used as a stand alone height control unit, in conjunction with a separate CNC unit or it can be used to control the contouring axes as well as the height control, reducing the electronics required on the machine to a minimum.

The height control unit can be used to independently control the height of multiple tool heads by simply adding an internal drive amplifier unit for each additional height control axis. This makes the AMC height control unit a very cost effective way of automatically controlling the height of multiple cutting heads.

Noise Immunity

The AMC height control unit requires a 0 to 10 volt input signal into the back panel of the controller to monitor changes in cutting height. If the application is particularly noisy (for example when plasma cutting) an extra conversion unit can be provided to take a higher voltage signal and convert it into a suitable noise free voltage range.

Corner/Edge Detection

The height control function can be inhibited manually or automatically (used in plasma applications to prevent the torch from diving at corners due to arc voltage increasing during deceleration).

Automatic Surface Detection

This feature allows the AMC to automatically move the cutting head towards the material surface, stop when the material is reached and back off the cutting head from the material by a set distance. This distance will then be automatically maintained throughout the cut.

Typical Applications

The height control unit is currently being used to maintain a constant arc length for plasma cutting systems and a constant focal length for laser cutting systems.

In plasma applications the height control unit extends the life of consumables, reduces or eliminates dross, increases squareness of the cut edges and maintains a consistent kerf width over the entire job, producing quality products.

In one plasma application the height control unit controls the z axis of a small trepanning table, mounted on the end of a robot arm. The height control unit automatically follows the complex surface of a formed metal object producing a high quality of cut without having to program the unit with the fine detail of the surface.

In laser applications the height control unit provides a uniform cut depth and width throughout the job. Up to 8 focal length settings may be configured and selected from within the part program. This allows the width and depth of cut to be varied without the need to interrupt the execution cycle or override manually.

• Improved Cut Quality
  
  
• Supplied as an integral part of a profiling machine controller or as a stand alone height control unit
  
  
• Noise Immunity
  
  
• Corner/Edge Detection
  
  
• Automatic Surface Detection
  
  
• Stable Height Control