Combined hard turning and
grinding from Dutch fi rm Hembrug,
a company that has recently been
acquired by Spain’s Danobat
Below the
surface at EMO
Mitsubishi Heavy Industries (MHI)
gave a European launch to the
world’s rst generating internal gear
grinder ZI20A. This machine achieves an
ef cient and highly accurate process in mass
production, using high speed spindles and
barrel-shaped grinding wheels that generate a
surface, rather than form grind it. Planetary
gears, ring gears, are the target and the
machine has a capacity of 200 mm, but there
is exibility in that. Sub-micron form accuracy
is achieved. “We are the leading company for
internal gears; no one else is making such a
machine at the moment,” Keiichiro Iwasaki,
president and CEO of MHI told Machinery at
EMO.
GRINDING & SURFACE FINISHING LATEST GEAR FOR GEARS
Andrew Allcock provides a fast recap on high precision gear grinding
developments at the recent EMO show. They highlight the drive for
ever higher precision gears to support the needs of electric vehicle
gearboxes, robots and the aerospace industry
The machine is driven by a FANUC CNC
unit, but a standard system is unable to
achieve the required accuracy, MHI says.
It has signed an agreement with FANUC that
allows the control maker to bene t from MHI’s
knowledge, with the outcome exclusively
available to MHI.
This internal gear grinding technology is
particularly important to support electric
vehicles (EVs), including multi-speed hybrid
EVs, single-speed EVs and those with the
proposed new two-speed transmissions.
MHI says that it is highly
likely their powertrains will rely on planetary
gear systems as their key speed-to-torque
conversion component. These planetary gear
systems for EVs rely on smooth internal gears
to deliver the desired driving experience.
A further demand for planetary gears is
the robot market, Machinery was told at EMO,
and this is another area of application.
Machines are installed in Japan, China, USA,
Mexico and, most recently, in Europe, at
Aachen university, Iwasaki added.
A challenge with the production of such
high accuracy gears is their measurement,
however, and the company said that this is
an area of development that it is involved
with, but no details were offered.
ONE-HIT GRINDING
Also targeting high accuracy cycloid gears for
robotics is Klingelnberg, with its Viper 500
MFM, which, it says, will set new “standards
of ef ciency in the robotics industry”. The
company’s Oerlikon G 35 bevel gear grinding
machine will additionally support this.
The Viper 500 MFM makes possible the
production of highest accuracy cycloid gears,
avoiding the need to measure and pair
Klingelnberg’s Viper 500
machine is for high accuracy
cycloid gear production
www.machinery.co.uk @MachineryTweets December 2019 33
/www.machinery.co.uk