TG-12x8 Hi-Accuracy system
This grinder is set up to Infeed Grind a solid 1-1/4 inch diameter part of hardened steel. The overall part length is 7 inches. The operator places a part in the Part Perch and slides the part between the wheels against the positive stop. The Ram Bed position control moves the Ram Bed through the Grind routine and the part is ground to precise tolerance. When the Ram Bed has retracted to the open position, the Part Ejector Slide Assist Mechanism retrieves the part and places it back on the Part Perch for retrieval and inspection by the operator. The machine is ready for repeating this procedure in this Semi-Automatic Mode. With not much more integration, we can completely automate this Part Handling system for a high volume production application.
It offers a grinding wheel diameter of 12" (300mm) and a regulating wheel diameter of 8" (203mm), both being 8" (203mm) wide. The advantage is clear, wider wheels allow for heavier stock removal for thrufeed grinding and multiple parts for infeed grinding.
The grinding wheel spindle design has 4" (100mm) diameter bearings, with three sets of class 7 ABEC angular contact Timken bearings inside a larger headstock with an outboard self centering bearing set for a twin grip design. This design gives the grinding wheel spindle superior rigidity. The regulating wheel, with its 2.25" (57mm) spindle and Timken bearings allows for the most demanding applications to be ground with zero deflection. The 8" (203mm) diameter regulating wheel allows for closer tolerance with larger diameter work.
The machine sits on our 8" (203mm) thick Starrett surface plate quality granite. The granite, known for its rigidity and thermal properties, provides a superior platform to other machines on the market that have thinner cast iron beds, and makes it as strong as those with machine platforms twice the physical size of the TG-12x8.
With these newer spindles and machine bed and base, wheel dressers are offered as Air Sensing, Automatic dressing, over the wheel CNC as well as Rotary Diamond Disk CNC platforms. On the TG-12x8 we upgraded our regulating wheel servo drive with 170 foot pounds of continuous torque, with an 8:1 gearbox.
Ram bed positioning has also been upgraded with a longer and wider ram bed. The Ram Bed travels over Cross Roller Ways for frictionless movement. The Ball Screw and Direct Coupled Servo Motor is controlled by a Parker Motion Control EPL system to deliver fine Ram Bed Position adjustments when Infeed and Thrufeed Grinding. The movements reference directly from the .1 micron glass scale linear encoder. The entire Ram Bed swivels with the Work Rest Holder to simplify adjustments and changeovers. The Operator Control Screen provides digital setting of Regulating Wheel Speed, Ram Bed Position, Wheel Dressing parameters as well as Infeed Grind parameters and many other machine controls.
Other companies talk about their intelligent machine controls to mask their basic limited machine designs. The TG-12x8 started with a robust spindle design and worked its way out.
The TG-12x8 is available for all types of loading applications including pick and place, robotic, and bowl feeding. In our booth at MDM WEST we have two systems, a TG-12x8 Wire Grind with a Robot Wire Feeder, and a TG-12x8 Hi-Accuracy system infeed grinding a large diameter part.