NEW LARGE GEAR MACHINES UNVEILED

Volume 10, Issue 2
Machine Tool Division
Gear Technology Center
46992 Liberty Drive
Wixom, MI 48393
248.669.6136
mitsubishigearcenter.com
NEW LARGE GEAR
MACHINES UNVEILED
at Mitsubishi Open House.
Ritto, Japan: May 27-28,
Mitsubishi Heavy Industries
Ltd. launched the sales and
marketing efforts for a new
line of large diameter gear
hobbing, shaping, gashing
and grinding machines
during a two day open house.
IN THIS ISSUE:
Doors Opened
to Innovation
TECH CENTER:
Good Hobs (Part 2)
Q2 2010
PAGE 2
PAGE 3
PAGE 4
Enhance Your
Productivity for Less
Each day, following technical
presentations to groups of
around 100 customers and
dealers, MHI conducted
plant tours to introduce two
of these new machines. On
the assembly floor was the
new GEA1200, the smallest
machine in this new line of
gear hobbing machines that
can be built with a capacity
up to 4 meters. Equipped
with a highly rigid hob head
(cont’d on pg. 2)
(cont’d from pg. 1)
and work table, the GEA1200
can accommodate highefficiency, high-precision
machining of gears up to 1.2
meters in diameter. Sitting
next to the GEA1200 was the
new ZGA2000 gear grinder
with a capacity of grinding gears
up to 2 meters in diameter.
Equipped with an on-board gear
measuring system and directdrive table motor, the ZGA2000
will meet the growing hard
gear finishing needs of wind
turbine, construction, mining,
paper mill and other industries.
MHI is also producing new gear
shaping machines and gear
gashers with capacities up to
4 meters. This new range of
large gear cutting and grinding
machines compliments the
well proven machine designs
that are also offered by
MHI. These include the MVR
range of precision bridge type
milling machines and the
large horizontal and vertical
machining centers. With this
full range of large machine
products MHI is uniquely
positioned to be a “one source
machine supplier” for the
aforementioned industries.
CREATIVE AUTOMATION
Throws The Doors Open!
Over a three day period commencing April 20th,
Creative Automation of Ypsilanti Michigan
arranged an open house displaying diversified
products from a number of well known
manufacturers and customers alike. Alongside
the Mitsubishi “gear machine” table top exhibit
were companies such as:
Altratec –
Conveyor Systems
Fanuc Robotics –
Displayed a working cell
Fibro –
Gantry Loaders
TRT –
Oil Off Systems
Pneumatics –
Air Servos and
Remote I/O Systems
EFTEC –
Wax Sealing of Car and
Truck Body Cavities
Since 1992, Creative Automation has come a long way
from their small Ann Arbor beginnings to their present
day, 45,000 sq. ft. ISO9001, facility in Ypsilanti. Their
customer list reads like a who’s who in the automotive
industry, having supplied automation and turnkey
systems to the likes of:
American Axle
Bosch
Chrysler
Ford Motor Company
General Motors Corporation
Honda (First Tier Supplier)
Creative Automation
(Solar Panel tracking device)
With a diversified supplier base coming from countries such as Brazil, India, England, Germany
and Russia, Creative Automation have become masters of managing logistics. Not content with
the success attained so far, Creative Automation now has an office in Shanghai, China which is
covering the burgeoning markets of the Far East and Asia and an office in Querétaro, Mexico to
cover their installations in that country.
For more details about
this exciting range of
products view them at
mitsubishigearcenter.com.
By the end of the open house on April 22nd, 85 customers had passed through the doors and
learned a lot more about the diversified capabilities of their host. Mitsubishi thanks Creative
Automation for inviting them to participate in this Bi-Annual event.
For more information about
Creative Automation visit their
website at cautomation.com.
mitsubishigearcenter.com
Q2 2010
Only Good Hobs
Produce Good
Gears (Part 2)
I
n the last issue of Gear News we began a discussion
on the influence of sharpening errors on the accuracy
of gears produced in the hobbing process. Last month,
flute rake error and its effect on gear accuracy was
explained in detail. In this article we will cover two
additional re-sharpening errors:
TECH CENTER
• Flute Spacing Error
• Flute Lead Error
Spacing error effect takes on many forms depending on
whether an adjacent or non-adjacent flute spacing error
was made during tool sharpening. The adjacent flute error
as in Figure 1 is simply changing the position and thickness
of the teeth. The ratio of 0.016” spacing error generates
tooth positioning error of 0.001”. This typically is caused
by a sharpening machine with good indexing accuracy
where a setup error was made due to an off center grinding
wheel. Non-adjacent flute spacing error may show different
symptoms. The involute of the tooth will be distorted and
lead variation of the tooth will be in error. This usually is
caused by a sharpening machine with poor index accuracy
or excessive hob runout during sharpening. Because the
flutes show greater wear, under no circumstance should
more material be removed from any one flute as this would
create a large flute spacing error and a bad gear tooth
profile. Every hob should be inspected for index accuracy,
just like the new hob is usually certified by its manufacturer
and shows a chart index error where high and low teeth are
clearly visible.
Flute lead error may be caused by an incorrect setup of
the sharpening machine, a problem with the hold of the
hob in the machine, or simply due to wear and tear off an
older machine. The typical result of this error is a distorted
involute of the tooth which is asymmetrical and creates form
of the leaning tooth. As is shown on Figure 2, the lead error
of 0.016” will cause a loss of 0.032” of tooth height affecting
tooth leaning by approximately 0.0003”. On the involute chart
of the gear the effect would be that all involute tracings
would also lean to one side. In the course of shifting across
the hob, the work tooth leaning direction would change
from one side in the beginning of usable hob to the opposite
direction toward end of hob.
The flute lead, or parallelism error, is not affecting the
gear tooth profile as much as the flute spacing. This is true
because only a small portion of the hob is used to generate
teeth on the gear. It is interesting to note that a flute lead
Q2 2010
FIGURE 1:
Influence of Spacing Error on tooth accuracy.
FIGURE 2 :
Influence of Flute Lead Error on tooth accuracy.
error, because of cam relief on the hob teeth, creates a
tapered hob. As a result, the hob OD should be measured in
few different places, keeping in mind that the gear size could
be affected. Again, a new hob should always be certified and
have a flute lead chart attached to it.
Final Note: Hobs sharpened outside of standard tolerances
cut inaccurate teeth. This leads to unsatisfactory gear
performance and often to early gear failure.
mitsubishigearcenter.com
Page 3
PRESORTED
FIRST-CLASS MAIL
U.S. POSTAGE
PAID
Machine Tool Division
Gear Technology Center
46992 Liberty Drive
Wixom, MI 48393
AOG
Incredible Productivity For
25% Less Capital Investment
Mitsubishi Gear Center is proud to offer 25% off our
GB100 CNC Slant Head Hobbing Machine. Depending
on your options, this could save you up to $250,000.
With an innovative slant-type head and a capacity of up to
1 meter and 1 DP, this enhanced machine is in-stock and
ready to produce gears for a wide variety of applications.
Features:
• Full 5 Axis CNC
• Enhanced Cutter Dimensions
• Increased Horsepower and Torque
For information about this special offer
call 248-669-6136 or reply by E-mail to:
ian_shearing@mhiahq.com.
Offer ends soon, so act quickly!
Page 4
GB100
mitsubishigearcenter.com
Q2 2010