BORING CARRIAGE

Stress released high quality Cast iron made, the infinity variable feeds are granted through A.C. Brushless motors controlled by its electronic digital drives. The transmission is obtained with pinions engaged on a helical-toothed rack fixed in the center of the bed, with a special drive that permits the compensation of the thrust forces and moves backlash-free or by an oversized high precision Balscrew with high torque motor.

Carriage guides have antifriction material (TURCITE) for a precise and accurate movement to avoid any stick-slip problems even at low feed speeds. Taper gibs provides precise adjusting of carriage geometry. The guides lubrication of the carriage is automatic and centralized lubrication control provides trough autonomous electropump and tank. There is an electric oil level signal to control whenever there is a lost of oil and gives directly the message to the CNC.

In order to optimize any resistance the drive is duly dimensioned with big torque and low inertia, in order to achieve high acceleration. Scrapers grant the fine and good cleaning of the guideways’ surface.

To control and save the pieces and tools there is a carriage movement overload protection that is electronically made directly on the digital motor drive, that, during machining when the tool force comes to limit is working as follows:

• Feed stop of boring carriage

• Automatic backward motion of boring head from about mm. 20 (opt)

• Spindle stop

• Pumping station stop

ROTATING BORING HEAD/SPINDLE

Headstock

The head, casting made, mounted on the boring carriage, is of a box double walled structure, appropriately dimensioned with suitable ribs. It offers maximum rigidity and ensures chatter free operations, also during the most severe working conditions.

Some of the main features of our machine spindle/boring head are as follows:

• The well ribbed headstock ensures maximum heat dissipation.

• Thick cast iron casing absorbs cutting vibrations

• Large angular thrust bearings for heavy duty boring operations

• Roller bearings with large bearing areas for increased spindle rigidity.

• P4 class front roller bearing ensures smooth even turning and has high radial load capabilities.

• To increase spindle stiffness and ensure longer spindle life the spindle shaft is surface hardened at the bearing contact points before the final grinding process. This provides a tough inner core to absorb the cutting forces while the hardened areas at the loading points prevent rapid wear on the spindleshaft, thus producing a long lived spindle.

• The latest computer analysis techniques are used for bearing arrangement on the spindle shaft to ensure optimum stability in the spindle structure.

• Thick Meehanite cast housing absorbs and dampens cutting vibrations.

• Well ribbed housing quickly dissipates heat from bearings and improves cutting accuracy.

• To optimise headstock design, computer simulations and dynamic analysis are performed to better understand the stress applied to the headstock during heavy cutting.

• After headstock assembly, each spindle undergoes running tests for 8 - 24 hours to ensure bearing temperature is not excessive.

The speed-change gear box can be manual or hydraulically/servo controlled, and the shifting is confirmed by means of light indicators. The speed-change can be directly carried out through functions "M" or, in case the machine is manually operated, by the appropriate switch on the control panel.

By the control unit, the spindle speed values are directly programmed in R.P.M. The lubrication of all power transmission parts is ensured by a forced circulation unit, which supplies the oil mist to all mechanism in movement and is controlled by a flowswitch.

FORCED LUBRICATION

central automatic lubrication system

All slideways and moving members are automatically lubricated. Lubrication channels are milled into the underside of the carriageway and turret to allow oil to be constantly forced between the moving members for added machine life.

The lubricant is controlled through pressured system that monitors the amount of oil in circulation. Any leaks or pressure drop will be detected immediately and result in an alarm being displayed on the controller. Excess oil from the Z-axis slide ways is caught by a ledge cast into machine bed which is collected in a sump at rear of the machine. This keeps the coolant form being excessively contaminated by lubrication oil.