"The new Cranfield Precision TTG machine is a radically new concept," said a company spokesperson. "While conventional machine tool platforms use stacked linear axes as the primary motion control system, the Cranfield Precision range coordinates two rotary axes and a short linear axis in a Twin Turret design. It uses a patented combination of rotary and linear axes to produce relative motion (both position and angle) between tool and workpiece over a swept working area."
"The Cranfield Precision platform offers two main advantages," said the spokesperson:
- Stiffness: the new machine base is effectively two rotary, highly damped hydrostatic bearings that resist machining forces.
- >Thermal stability: the Twin Turret design enables a simple non-contacting labyrinth seal, making the machine base almost immune to distortions. These are usually caused by the heat generated from constantly changing coolant return path as the grinding wheel carriage moves along the linear axis.
This design provides a common platform for multiple machine configurations and processes, including O.D. grinding, I.D. grinding, profile grinding, milling, polishing, hard turning, diamond turning dicing and in-situ metrology.
The machine is supplied in two sizes: TTG100 and TTG400 for up to O100 mm and O400 mm components respectively.
The trend towards superabrasives demands a stiff and thermally stable machine geometry. The new design of this Cranfield Precision machine responds to the needs of the most demanding applications:
- The optics industry for grinding spherical, aspheric and free-form surfaces on a wide variety of materials.
- Universal CNC grinding of more conventional parts held in a chuck or faceplate using aluminum oxide or superabrasives.
- Multi-function machining center offering grinding, milling, turning, polishing and measurement options on a single machine platform.
"The experience gained by Fives over many years for its Cranfield Precision range of products in the optic industry show that ductile regime grinding of brittle materials can deliver considerable process advantages over conventional grinding processes," said the spokesperson. "This mode of operation is not possible to support unless the machine system is extremely stiff, highly damped and capable of sub-µm position control."
Fives has two primary versions of the machine. Both versions of the machine use the same Twin Turret concept, but each is targeted at a different market.
The Landis LTT (Landis Twin Turret) is primarily for grinding, turning, polishing, milling and metrology of components either chuck mounted or between centers. This machine is available in the U.S. via Fives Landis Corp (U.S.)
The Cranfield Precision TTG (Twin Turret Generator) is primarily for grinding, diamond turning, micro-milling, pre-polishing and metrology of chuck mounted optical components. This machine is available in the U.S. directly from Cranfield Precision (UK) or via Fives Landis Corp (U.S.).
For more information contact:
Fives Landis Corp.
16778 Halfway Blvd.
Hagerstown, MD 21740
301-797-3400
landis-us-info@fivesgroup.com
www.fivesgroup.com