Thursday, June 29, 2006

Linear drives speed up sliding head automatic

Using linear motors to remove any likelihood of deflection and backlash from the power transmission system a very compact sliding head automatic offers super precision with high speed.
By using linear motor technology to remove any likelihood of deflection and backlash from the power transmission system and to optimise the structure of the slideway, Citizen has been able to create a very compact machine able to capitalise on combining super precision with high speed one-hit machining cycles and short cycle times on components up to 7mm diameter by 40mm long. As a result, the new Citizen R07 Type VI CNC sliding head auto is reckoned to be significantly faster than a traditional cam auto when machining parts in single cycles using the main and subspindle and up to 13 tools while maintaining a very compact footprint when installed on the shopfloor. The Citizen R07, launched in the UK by NC Engineering of Watford, UK, has no hydraulics or pneumatics and is totally electric and electronic in operation.

It has six axes, a 16,000 rev/min, 1.1kW built-in main spindle with ceramic bearings for optimised machining of small diameter parts and a 0.5kW secondary spindle with an 8,000 rev/min capability.

Having two independent toolposts able to hold 13 tools, of which two are driven by 0.2kW, 8.000 rev/min spindle, two tools are able to simultaneously machine a component.

An important development with the RO7, that significantly increases machine utilisation, is the ability to open and close the collet at normal machining revolutions without having to slow the spindle.

Accuracy is high with increments of 0.0001mm in each axis and repeatability of one micron is possible.

By combining linear drive technology to both tool posts, high productivity is guaranteed with rapid acceleration to maximum traverse rates of 20m/min.

The maximum machining length is 40mm and with the two slide arrangement, five turning tools can be mounted on the gang tool post with two cross-driven tool positions.

In addition, three end working tools can be applied to each of the main and secondary spindles to high orders of positioning accuracy through the use of glass scale encoders.

Drilling and tapping capacity at the main spindle is 4mm and M3 respectively with 2mm and M2.6 for the secondary spindle.

Driven tool a capacity is 2mm.

The main spindle has 1 deg indexing and both spindles have rotational synchronisation for part transfer.

There are a number of canned cycles for polygon turning, thread cutting, drilling and rigid tapping and constant surface speed is standard.