The DAC DLL Series IV/2-Axis ALM is the most versatile of all DAC contact and intraocular lathes. It incorporates the latest technology in air bearing slides and linear motors with linear encoder feedback. The DAC ALM also brings solutions to diamond turning non-ferrous metals. 

Each axis is driven by linear motors with position feedback from linear encoders with 10 nanometer resolution. The technology of the air bearing slides eliminates air restrictor ports through the use of new technology. This technology provides ultra smooth motion that translates to ultra smooth surface finishes. 

The lathe base is a 200 mm thick granite surface plate for accuracy and stability. The surface plate is mounted with vibration isolators on a welded steel frame. The complete machine and electronics are housed in a single cabinet.

 The Z axis is mounted directly to the granite and carries the spindle. The X slide is also mounted on the granite and precisely positioned at 90o to the Z slide. This machine geometry assures the machining loads are well centered within the travel of the slides and that the spindle mounting is stiff and stable.

 Multiple sets of tooling and a front surface gauging system are mounted on the X slide. The optional Oscillating Tool Technology (OTT) system can be added at the time of purchase or later to meet customer needs. The lathe spindle is a carefully balanced, air bearing high frequency unit with programmable speeds of 0 to 18,000 R.P.M. An AC motor drives this spindle. A DC motor with encoder feedback for the OTT option, provides torque at all speeds and the ability to synchronize with OTT tooling.

The part to be turned may be held in the collet or blocked to an arbor for turning. Special collet arrangements are also available upon request. The roughing natural diamond tool is used to remove the bulk of the material. As the finishing tool removes only a minimal amount of material, its edge (and life) is preserved. 

All cuts are made by Z or X motion, or by ZX interpolation. Any number of spheres and aspheric surfaces (front or back) can be turned. In addition, with the OTT option, the complete range of toric and atoric front and base curve surfaces can be turned. DAC has developed more than 40 algorithms that laboratories use to create their own special lens offerings. These include lenses that are spheres, aspheres, torics, atorics, bitorics, and keratoconus solutions for their clients. Because of the fine resolution (.010 micron) the surfaces require little or no polishing, depending on the material used and the manufacturer's process.

Edge radiusing is accomplished by utilizing a special tool with ZX interpolation to produce the desired contour.

Typical contact lens base and front curves can be produced in 30 to 60 seconds, depending on geometry and material used. Very complex crescent toric segmented bifocals may take as long as four minutes to complete.



Operator Machine Interaction

"Menu" type queries, on the color monitor screen, guide the user quickly through machine set-up, calibration, alignment and tool replacement. DAC Script Language (DSL), which employs a subset of RS-274D machine language, is a high level programming language that is easily understood by the user and is included in each lathe.

If all lens design parameters are known, the user simply enters the appropriate numbers by use of the keyboard. The machine will calculate variables, such as junction thickness, after the entry of the basic design factors. A display of a lens cross section aids the user in the design process by graphically presenting the actual design. The machine's computer automatically converts the lens design specifications in the machine language program necessary to machine the desired part.

DAC software presents the laboratory with many, many options for the creation of lenses to meet the most demanding requirements. 

The DAC Digital Motion Control (DMC) system is at the "heart" of all DAC Lathes. It is housed in the on-board computer, mounted with the servo amplifiers, in the base of the machine behind interlocked doors for easy access.  Each axis is driven by a linear servo motor with linear encoder feedback.

Auxiliary functions such as actuating lights, vacuums, air blow-offs, autoloaders, etc. are controlled by outputs from the programmable logic control.

Both roughing and finishing tools are held in newly designed, micro-positioned holders that keep the tool parallel with spindle center. These robust tool holders are adjustable to accommodate a wide range of tool shank sizes.

The Oscillating Tool Technology (OTT) holds a diamond insert and is adjusted in the same vertical manner.

Slides: Linear slides are DC linear servo motor with linear encoder feedback

 

Type: Travel: Resolution:

X Air bearing 203 mm (8") 10 nm (.4 micro-inches)

Z Air bearing 152 mm (6") 10 nm (.4 micro-inches)

Accuracy (incremental):

Center Thickness Diameter Radius of Curvature Traverse Rates:

+ 2.5 microns (0.0001")  + 5 microns (0.0002") + 2.5 microns (0.0001") 5 meters/min (200 I.P.M.)

Spindles:	Air bearing Synchronous motor spindles -  6,000 to 18,000 RPM  DC servo motor/encoder spindles -  0 to 10,000 RPM with .036 degree resolution
Collets:	A wide variety of collets are available and supplied with the lathe.
Diamond tools:	A complete set of diamonds are supplied with each lathe.

 

Installation Data

Power:	208, 220, 230, 240 VAC, 1 phase, 50/60 Hz, 20 Amps
Air:	2.75 CFM @ 80 PSIG (4.7m3/Hr. @ 5.6 Kg/cm2)
Temperature:	68 to 74 Degrees Fahrenheit
Vacuum:	User Furnished 3.2 cm (1.25") Diameter Manifold
Floor Space:	1,219 mm x 1,270 mm x 1,778 mm (48" x 50" x 70")
Weight:	Floor - 1,089 kg. (2,400 lbs.)  Shipping - 1,225 kg. (2,700 lbs.)