Nidec launches ZFA Series of high-precision gear grinders

A gear grinding machine from the Nidec ZFA Series

Nidec Machine Tool Corporation, a Nidec Group company, has developed the ZFA160 and ZFA260, a pair of global-standard gear grinders to meet the global needs for high-precision gear machining. The company has specifically designed the two new models in response to the rising needs for high-precision, stable, and high-performance production of gears for electric vehicles’ (EV) transmissions and robots’ speed reduction mechanisms.

Nidec Machine Tool debuted the machines’ capabilities at Japan International Machine Tool Fair (JIMTOF2024) last week. The two machines were seen working live, while performing a demonstration of inline workpiece (units to be machined) measurement for complete automation, alongside automated carry-in and take-out operations by TR-20W, a carriage-type robot system developed by Takisawa Machine Tool Co Ltd, to provide complete solutions for gear machining.

The two ZFA Series gear grinders are designed to perform high-speed and high-precision finish machining on gears and are each designed for a different gear size range, with the ZFA160 capable of handling gears with an external diameter of up to 160mm, and the ZFA260 accommodating gears with an external diameter of up to 260mm. Capable of meeting the increasingly sophisticated users’ needs — both machines can mass-produce gears with a gear accuracy level equivalent to ISO 3 (JIS level N3).

In regard to their high-speed machining performance, the two models feature a newly developed twin-table structure and high-speed rotary performance, reducing non-machining time to 4sec — 33% faster than the current ZE16C model and 50% faster than the ZE26C. In addition, to achieve high-precision machining that is stable, the ZFA160 and ZFA260 employ stiffer work-table structures, grinding stone heads, and dress units.

High-speed machining
Furthermore, the models’ main axis structures were made to endure high-speed machining, while, for their machines’ heads (boards to comprise the machines’ main units), a thermostable material (mineral cast), which suppresses vibration from high-speed machining and heat-caused dimension change, has been adopted to stabilise accuracy during high-volume production.

The ZFA160 and the ZFA260 are also ideal for machining gears for EVs, with features such as ‘simultaneous double-tooth flank bias adjustment’, a function to suppress distortion on flanks, and ‘low-noise machining’, which reduces periodical asperity on tooth flanks, among many other high-precision machining technologies.

Also, as part of actions to curb environmental load, the users of the two latest models can select a circular, filter fabric coolant tank to process sludge and coolant containing waste from the machining process, resulting in reduced industrial waste.

As vehicles become electrified, quieter, more fuel-efficient, and cheaper, there is a globally growing need for the high-precision finish of gears and the mass production of precision gears. In addition, as the demand for a variety of reducers for high-performance robots increases, demand is growing for gear grinders capable of high-speed and high-precision machining.