August 23, 2012
A Penton Media Publication
Tune in to EngineeringTV.com
COOL
TECHNOLOGY
Advanced manufacturing
techniques promote
innovation,
page 42
MORE EFFICIENCY
FROM COMBUSTION
ENGINES, page 38
GLASS SPHERES
MAKE LIGHT WORK
OF BOWLING BALLS,
page 48
POSITIONING WITH
PIEZOELECTRICS,
page 54
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VOLUME 84
ISSUE 12
AUGUST 23, 2012
ENERGY EFFICIENCY
Even though combustion engines that use pistons and
cylinders have been around for almost a century and a
half, inventors and engineers are still coming up with
new versions that improve efficiency and burn a wider
range of fuels. Some of these new engines may not be
practical or economical, but it’s difficult to know that
without building one first.
Here are several new approaches, or at
least variations on earlier efforts, that
offer a twist on conventional internalcombustion engines (ICEs). And although it is unlikely they will be embraced by major automotive builders — they have their own engine2
modification programs and efforts
— there are rumors of deals with
Asian companies making small
cars, scooters, and self-powered
equipment such as generators and
lawn mowers.
The Cyclone engine
FEATURES
The Cyclone engine from Cyclone
Power Technologies, Pompano Beach, Fla., is an
external-combustion
steam engine that can
be powered by heat
from practically any source, including biodiesel and syngas, according to the company. It is the basis for a new
10-kW auxiliary power unit being built for the Defense
Dept. and the U. S. Army Tank Command, where it
could see service on the M1 Abrams tank, IAV Stryker,
and Bradley Fighting Vehicle.
The engine uses the Rankine Cycle and regenerative external combustion, a combination the company calls a
Schoell Cycle engine.
Four basic processes
take place inside the
engine:
Heat process: Atomized fuel injected
into the centrifugal
combustion chamber
1
mixes with air and is
ignited. Thermocouples
control combustion duration
to keep heat in the chamber at
a constant temperature. The
heat then swirls around
3
the heat coils. Water in
those coils becomes
superheated steam
(up to 1,200°F)
4
and gets piped to
During operation of the
Cyclone engine, fuel is
injected and burned in
a centrifugal combustion
chamber (1). Water in coils
becomes superheated (2), then
enters an adjustable valve (3), which
distributes the steam into six radially
configured cylinders. The pistons’
motion turns the crankshaft (4). Steam
escapes the pistons and is collected in a
condenser, where it is turned back into a
liquid (5). Blowers send fresh air around the
condenser to speed cooling (6).
5
6
copper tubes make
42 Small
a big impact on airconditioner efficiency
New developments in copper-tube
technology could pave the wave for morecompact condensers and air conditioners.
Engineers and inventors
continue to tweak and
refine piston-based
combustion engines.
On target
with
off-beat engines
38
MACHINE DESIGN.com
AUGUST 23, 2012
places with
54 Going
long-travel piezomotors
Piezomotors offer many advantages in
size, speed, vacuum compatibility, and
resolution, but haven’t been able to span
long distances. That’s changing.
fluid circuits with
60 Protecting
edge-welded bellows
Compensating for expanding fluid
protects equipment and prevents leaks.
AUGUST 23, 2012
38
lose weight
48 Plastics
with glass bubbles
Older grades of glass bubbles were
only suitable for zero to low-pressure
processes. New glass bubbles are stronger
and small enough to meet OEM Class A
surface finish standards.
Authored by:
the cylinders through an adjustable valve. Valve timing
Stephen J. Mraz
determines how much steam enters the cylinders, which
Staff Editor
controls torque and acceleration.
[email protected]
Mechanical process: Steam enters each of six radiResources:
ally configured cylinders under pressures as high as
Cyclone Power Technologies, cyclonepower.com
3,200 psi, pushing down each piston in sequence. Water
acts as the working fluid and lubricant — there is no
Doyle Rotary, doylerotary.com
engine oil. The pistons’ motion drives a spider bearing
Grail Engine Technologies, www.grailengine.com
to turn the crankshaft. According to the manufacturer,
Pinnacle Engines, www.pinnacle-engines.com
torque is greatest on the first rotation of the shaft, so it
To see the Doyle Rotary engine in action, doylerotary.com/
can be connected directly to the drivetrain without a
overview.php
transmission. In fact, a 38-in.3 Cyclone engine develops
over 850 lb-ft of starting torque.
To see the Grail engine in action,
Cooling process: Steam exits the cylinders through
youtube.com/v/4-H03_wGFB0
exhaust ports and enters a condenser that turns it back to
To see the Pinnacle engine in action,
a liquid, which collects in a sealed pan at the bottom of the
pinnacle-engines.com/technology.html
condenser. Blowers spin fresh air around the condenser
For another feature on innovative
to speed cooling. Because this is a closed-loop subsystem,
engines, scan this code or go to: http://
water need not be replaced.
machinedesign.com/article/rethinkingRegenerative process: Air heated by the condenser
engines-0308
travels to a heat exchanger where it preheats air coming
into the combustion chamber. A high-pressure pump
traditional gas or diesel engines of comparable power.
transfers water from the condenser pan to the heat coils
The company is currently developing at least five vervia heat exchangers around each cylinder, then to the censions of the Cyclone engine ranging from 5 to 330 hp.
ter of the coils to begin the heat cycle again.
This design yields several advantages, including:
They can be used for portable or auxiliary power, automoAll-fuel capability: Fuel burns in an external-combustive or marine propulsion, powering heavy-duty equipment, or scavenging waste heat.
tion chamber under atmospheric conditions to create
steam and power the engine. This lets the engine burn
Grail engine
fuels derived from orange peels, palm and cottonseed oils,
algae, used motor oil, and fryer grease, as well as propane,
The Grail engine looks much like a traditional twobutane, natural gas, gasoline, and even powdered coal. In
stroke engine, but incorporates some weight-saving refact, the engine can even run on waste heat from ovens or
finements that make it less expensive to manufacture. And
furnaces, as well as solar collectors.
its inventors at Grail Engine Technologies, Chapman,
Environmentally friendly: The engines
burn fuel longer than traditional ICEs,
This Cyclone engine
which means fewer carbon emissions.
has been adapted
At the same time, burn temperatures are
for use on relatively
lower, below the point at which harmful
small equipment,
NOx gases are created. No oil is used, so
such as a lawnmower.
there is no oil to change, dispose of, or potentially leak. And the exhaust is virtually
silent, unlike ICEs, which emit supersonic
sound waves into the air.
Efficiency: By keeping heat losses to a
minimum, the Cyclone’s fuel efficiencies
are on par with top diesel engines. It also
has a power density of about 2.5 hp/in.3, far
more than traditional ICEs, which put out
about 1.5 hp/in.3
Low cost: The Cyclone engine doesn’t
need a catalytic converter or muffler, nor
an oil pump or oil, and requires no transmission. With fewer parts, the engines is
less expensive to manufacture and assemble. And parts can be made of inexpensive,
nonexotic materials. The company predicts,
therefore, that the engine will cost lets than
On target with
off-beat engines
MANUFACTURING & AUTOMATION
Made inthe
U.S.A.
Is manufacturing
in the U. S. dead
and gone?
The answer to this question —
not really. In fact, here are just a
few examples of companies —
either entirely based in the U. S.
or with large manufacturing
plants here — that have done
well even during the recent
downturn. They range from
high-precision machine shops
to carousel builders.
How to increase
positioning
accuracy
Edited by Leslie Gordon
[email protected],
Twitter @Leslie.Gordon
Machine shop produces
complex, precision parts
From simple screw-machine parts to highly precise, intricately detailed
parts, this shop’s up-to-date machines let it produce a wide variety of
products. Currently, the company’s in-house machines include those
with up to 12 axes, letting it perform multiple operations at once. The
shop also has vertical-machining centers and
a secondary department that uses processes
including thread rolling, knurling, polishing,
Swiss Precision Machining
slotting, deburring, drilling, and milling. The
Inc., 7550 N. Oak Park Ave.,
firm can machine many different kinds of
Niles, IL 60714, (847) 647-7111,
material, from 360 brass to 303 stainless and
www.spmswiss.com
Nitronic 60. It can also machine different
RS# 621
types of plastic.
Resources:
MACHINE DESIGN.com
Precision metric ball screws (PMBS)
provide a cost-effective, high-precision
actuator to aerospace, defense,
medical, machine, and tool-making
manufacturers. To make the screws, the
company uses advanced thread-rolling
technology, letting it manufacture highquality precision ball screws in a range
of sizes, diameters, and leads. According
to company officials, precision metric
ball screws provide a more cost-effective
alternative for accuracy-intensive
actuation and outperform standard
thread-rolled ball screws. Fully
compliant with ISO 3408-3 and DIN
69051 standards, PMBS such as the
MRT and PMT offer fine adjustment,
accuracy, and repeatability for tight
control positioning. The availability of
different mounting styles makes PMBS
ball screws a good, interchangeable,
domestically
produced
Resources:
replacement
Nook Industries Inc., 4950
for imported
E. 49th St., Cleveland, OH
44125, (216) 271-7900, www.
ground screws.
AUGUST 23, 2012
64
nookindustries.com
RS# 622
Made in
the U. S. A.
Here are just a few
examples of companies
— either entirely based
in the U. S. or with large
manufacturing plants
here — that have done
well even during the
recent downturn.
Access our Reader Service
Web site to quickly find and
request information on the
products and services found
in the pages of MACHINE DESIGN.
www.machinedesign.com/rsc
MACHINE DESIGN.com
AUGUST 23, 2012
39
Inventors are refining the traditional
combustion engine in search of more
power and efficiency from lost-cost
alternatives.
64
2
MACHINE DESIGN.com
P3-HSO
2-channel
High-speed Output
$
349
P3-HSI
2-channel
High-speed Input
Pulse/Direction,
Quadrature X1
and Quadrature X4
329
$
Pulse/Direction,
Step Up/Step Down
and Quadrature
With the Productivity3000
controller, you get the power you
need for advanced applications.
Simple Instructions
Start with the $599 CPU - 50Mb of memory supports
large programs, with tagname database and program
documentation stored onboard. The huge (100,000+)
I/O capacity gives you plenty of room to plan and
expand. And the CPU’s seven built-in communication
ports make integrating a large system easier than
you can imagine.
Our standard instructions were designed to make your
everyday motion applications simpler. The Find Home, Set
Position, Simple Move and the Velocity Move instructions
(to name a few) were created to get you up and running
sooner. Capabilities such as Registration, Jerk Control and
Channel Scaling were included to give you the flexibility
to accomplish those jobs.
Now with High-speed Motion Control
Application Example
These new 2-channel modules add high-speed and motion
control applications capability to the Productivity3000
controller, and they’re easy to use! Add up to 22 P3-HSO or
P3-HSI modules in any combination to any P3-550 CPU and
P3-RS base group. That gives you up to 44 axes of motion or
high-speed counting capability in a single base group. These
modules are supported and fully functional in the CPU base,
local and remote expansion bases.
High-speed outputs synchronize the
speed of the servo drive controlling the
fill conveyor. The conveyor is
synchronized with the rotational speed
of the turntable based on the
signal(s) from the table
encoder feedback via the
high-speed input module.
P3-HSI
P3-HSO
Drop-in Hardware Configuration
Install a high-speed module into the system hardware
configuration and define each channel’s behavior, status bits,
limits and scaling … without the need for an external
configuration utility or software.
A
Download the free
programming software
and check it out!
B
VELOCITY MOVE
Module Name: Feed Conveyor
Channel: 2 Channel Name: CHAN-2-0.1.1
Move Setup
Machine Process Start
1
Enable
Direction Positive
Velocity Fill Index Speed
500
Ramp Rate Conveyor Ramp Rate
1000
Stop Setup
Immediate Stop
In Progress ConveyorMove In Progress
1
Complete Conveyor Move Complete
0
Move Status Conveyor Move Status
2
http://bit.ly/p3000
RS# 103
ON THE COVER
DEPARTMENTS
MicroGroove tubes courtesy of the
International Copper Association.
8 EDITORIAL
Bad math for fixing bad math scores
10 EDITORIAL STAFF
12 LETTERS
16 SCANNING FOR IDEAS
Machine inserts different-sized pins in the same assembly
Pneumatic actuator handles linear and swiveling motion
20 REPORTER’S NOTEBOOK
30 LOOKING BACK
37 COMMENTARY
The attack of the CAD jockey?
73 ORR ON ENGINEERING
Be more productive
74 SOFTWARE REVIEW
Software simulates mechanical systems
with chains, gears, and belts
76 SOFTWARE PRODUCTS
78 PRODUCT SPOTLIGHT
Gears & gearmotors
82
90
92
93
94
94
95
PRODUCTS
DATA FILES
AD INDEX
BUSINESS INDEX
CLASSIFIEDS
BUSINESS STAFF
BACKTALK
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4
MACHINE DESIGN.com
AUGUST 23, 2012
POSTMASTER: Send change of address notice to
Customer Service, MACHINE DESIGN, P.O. Box 2100, Skokie,
IL 60076-7800.
How To Keep Your Electronics Cool
When hot weather causes the electronics inside a control cabinet to fail, there is a panic to get the machinery
up and running again. There are several cooling options out there and it’s important to know the facts.
line up of coolers that are prone to bad behavior
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and aiming a fan at the
circuit boards is a bad idea.
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and dirt clogs the filter.
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The “plastic box cooler” from a
competitor uses an inaccurate
mechanical thermostat that’s
designed for liquids. Th is
thermostat has a poor ability
to react quickly to changes in
air temperature.0[JVZ[Z\W
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EXAIR Cabinet Cooler ® Systems
EXAIR has a complete line of Cabinet Cooler Systems
to dependably cool and purge your electrical enclosures.
They convert an ordinary supply of compressed air into
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clean, cold 20 ºF air. They mount in minutes through
h an ordinary
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electrical
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knockout and have no moving parts to wear out. The compressed air filtration
that is provided keeps water, oil and other contaminants out of the enclosure.
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the temperatures of the room
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www.exair.com/45/440b.htm
If you would like to discuss
an application, contact an
Application Engineer at:
Manufacturing Intelligent Compressed Air® Products Since 1983
11510 Goldcoast Drive-Cincinnati, Ohio-45249-1621- (800) 903-9247
fax: (513) 671-3363-E-mail:
[email protected] -www.exair.com
@EXAIR
RS# 104
What’s new online machinedesign.com
DESIGNENGINEERING
CONFERENCE AT IMTS
Engineers interested in the latest techniques for improving
machine efficiency, predicting failure and downtime
before it happens, and getting a look at controllers of the
future should attend The Motion, Drives and Automation
Conference, to be held September 10th and 11th in Lakeside
Hall of Chicago’s McCormick Place.
The conference is part of the IMTS Show and is
organized by MACHINE DESIGN and Hydraulics & Pneumatics.
It will feature two in-depth conference tracks running
simultaneously, Motion Control in Automation and
Hydraulics & Pneumatics in Automation.
Other topics include security in industrial automation;
mechanical and structural factors to consider when
designing high-speed, high-precision motion systems; and
“Think like a machinist,” which will offer practical tips on how
to design easier-to-manufacture components. The fluidpower track will include sessions on closed-loop position
and force control; and designing more-reliable, efficient, and
quieter systems. Learn more at www.imts.com/education/
motionConference.html.
Electric ZTR mower
EDITOR’S WEB PICKS
Editor Leland Teschler talks to the owner of specialty vehicle manufacturer
Lawless Industries about an all-electric 60-in. cut zero-turning-radius lawn
mower. It has five permanent-magnet dc motors and can cut up to four acres
on a single charge. Advantages over gas-powered machines include no exhaust
and much quieter operation. See
it mow at www.engineeringtv.com/
video/All-Electric-Lawn-Mowers-atLaw;Only-Engineering-TV-Videos.
6
Editors Web picks
Product-configurator tool
Overnight motors
Wittenstein’s Product Configurator Design Tool fills
the gap between the company’s online Product CAD
Generator and Cymex servosizing software. The tool helps
engineers select and size gearboxes
and includes a gearbox-to-motor
system configurator and a database of
over 7,000 motors. Learn more at www.
wittenstein-us.com.
PittmanExpress is an online system for ordering
prototype parts that ship in 24 hr. Users can quickly
obtain brush-dc,
brushless-dc, and gearmotors
in various frame sizes and
ratings for concept testing
and evaluating products
for specific applications. For
more information, visit www.
pittmanexpress.com.
Comprehensive bearing catalog
NKE Austria’s new General
Catalogue runs more than 1,000
pages. It contains comprehensive
data on the company’s standard
bearings and information on
custom products. The technical
section helps engineers select
bearing types and sizes and
specify mounting locations,
lubrication, and tolerances. It also
contains additional technical data,
such as service life calculations,
fatigue limiting loads, and thermal
speed ratings. Order the free CD
or print version, or download it at
www.nke.at/catalogue.
MACHINE DESIGN.com
AUGUST 23, 2012
Power-supply Apps
TDK-Lambda has released the Power
Supply Glossary App for iPhone and
Android mobiles. It contains a library
of power-supply terms and provides a
useful selection of relevant calculators.
The company also offers a powersupply selector App. They are available
at http://us.tdk-lambda.com/lp/about/
phone-apps.htm.
Hydraulic brakes
MICO Inc.’s new Web site (www.
mico.com) covers hydraulic brakes,
actuators, valves, and controls and
offers info on vehicle dynamics. The
braking and stability-control systems
are intended primarily for heavy-duty,
off-road, commercial, and industrial
applications.
tick tock
Less downtime with every valve.
Power. Precision.
Performance.
Continental Hydraulics knows that time is money, that’s why we offer a
complete line of Proportional Directional Valves with integrated digital
electronics for maximum precision, durability and reduced hysteresis.
Our high performance valves are available in all standard NFPA mounting
patterns and flow ranges. The on-board microprocessor provides fast
response times, seamless interchangeability among valves and supports
software-based, hydraulic parameter modifications to ensure optimal
load movement. Factory calibrated for time-savings, output range
assurance and easy valve-to-valve exchange, our proportional valves
offer a smooth, shock-less motion and precise position control to reduce
down time, increase production rates and make every second count.
PUMPS
VALVES
POWER UNITS
RS# 105
952. 895. 6400 | www.continentalhydraulics.com
EDITORIAL
Bad math for fixing
bad math scores
It’s back-to-school time again, the time of year when kids get nervous about
meeting new classmates and their parents get nervous about poor schooling
in math and science. Despite a lot of attention over the past decade, scores
for reading comprehension, math, and science on the National Assessment of
Educational Progress have either stagnated or gone down. High-school graduation rates have also stagnated or declined.
But some of the measures undertaken to correct these trends might lead
you to conclude that school administrators and educational advocates, rather
than students, are the ones who could benefit most from better math skills.
Consider one of the measures that was supposed to improve the public secondary education: hiring more teachers. Since 1970, labor statistics show that the
public school workforce has doubled, with two-thirds of the increase devoted
to teachers or teachers’ aides. Meanwhile, secondary-school enrollment rose by
just 8.5%. It is fair to ask why no one in the educational infrastructure noted the
difference in these two trends long ago and began posing some hard questions.
An even-more interesting case of bad math arose in the late 1990s when the
Bill and Melinda Gates Foundation gave grants totaling about $1.7 billion to a
movement directed toward breaking up large schools into smaller ones. The
idea came from the claim that student achievement improves when schools
are smaller. The evidence for this assertion was that there is an unrepresentatively large proportion of smaller schools among high-performing educational institutions.
But there was a problem with the reasoning behind the smaller-is-better
movement. It was explained by University of Pennsylvania statistics expert
Howard Wainer and McGill University’s Harris Zwerling. Promoters of this
idea, said the two statisticians, either didn’t know about or ignored the findings
of French mathematician Abraham de Moivre who, in 1730, showed that small
samples have high variations. Specifically, he demonstrated that the standard
deviation isn’t proportional to the sample size, but instead rises in proportion
to the square root of the sample size.
It isn’t surprising that small institutions show up more frequently in lists of
better-than-average schools, the two said. The performance of small schools is
more variable than that of large schools, so overrepresentation at extremes is to
be expected. To prove their point, Wainer and Zwerling looked at the 50 lowestscoring schools in Pennsylvania, where they had academic data to work with.
It turned out that smaller schools were overrepresented in this group as well.
There were a lot of complaints about the smaller-school movement. It
emerged that “teachers ended up teaching things they don’t really know,” as
a Seattle newspaper article concluded. Speaking of the small-school movement, one Michigan State University educator said, “I’m afraid we have done
a terrible disservice to kids.” Eventually, the Gates Foundation stopped giving
grants to promote the idea.
Wainer has more direct comments on this episode. “Spending more than a
billion dollars on a theory based on ignorance of de Moivre’s equation ... suggests just how dangerous that ignorance can be.”
The economics Nobel Prize winner Daniel Kahneman also read about the
small-school debacle and said he found it “amusing.” One wonders if, after
spending close to $2 billion on a misguided idea, Bill and Melinda Gates are as
amused by it as Kahneman.
— Leland Teschler, Editor
RS# 106
AUGUST 23, 2012
RS# 107
OUR ANGLE IS…YOUR GEAR
SHIPPED IN 24 HOURS
OR IT’S
FREE.*
EDITORIAL STAFF
EDITOR
Leland E. Teschler
[email protected]
MITRPAK right angle,
three-way, and counterrotating spiral bevel drives
are interchangeable with
Boston Gear, Hub City, Browning…
and we guarantee 24-hour shipment.
MANAGING EDITOR
Kenneth J. Korane
[email protected]
SENIOR EDITORS
Leslie Gordon
[email protected]
Stephen J. Mraz
[email protected]
For complete specifications and
CAD files, log onto www.mitrpak.com,
or call us at 800-648-7725. Learn
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[email protected]
Robert J. Repas, Jr.
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RS# 108
INDUSTRY COVERAGE:
AUTOMOTIVE, PACKAGING,
MEDICAL
Stephen J. Mraz
CAD/CAM, MANUFACTURING
Leslie Gordon
ELECTRICAL, ELECTRONICS
Robert J. Repas, Jr.
FASTENING & JOINING,
MATERIALS
Lindsey Frick
FLUID POWER
Kenneth J. Korane
MECHANICAL
Lindsey Frick
Kenneth J. Korane
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EDITORIAL PRODUCTION
Denise Greco
Editorial Production Manager
Randall L. Rubenking
Art Director
1300 E. 9th St. Cleveland, OH 44114-1503
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MACHINE DESIGN.com
RS# 109
AUGUST 23, 2012
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RS# 110
LETTERS
Engineers are not CADs
I strongly disagree with the first
part of Leslie Gordon’s commentary (“Does Model-Based Engineering Make Sense?” June 14). She
wrote: “Design is merely creating
the geometry. Any CAD jockey can
do ‘design.’ Engineering, on the
other hand, uses physics-based
rules to develop functional machines and mechanisms.”
I believe she is confusing the
issue. It is certainly not true that
any CAD jockey can do “design.” It
might be true that any CAD jockey
can do drafting, which might be
classified as drawing what has already been designed. True design
can involve a huge amount of creativity, and it is concerned with
form, function, and costs, among
other things. Good designers may
also need to understand engineering fundamentals, and work hand
in hand with more analytical engineers to ensure the integrity of
their designs.
Not all engineers make good designers (although some do), because
they aren’t creative or don’t have the
common sense to get out of the
rain. They might be good computer
jockeys, number crunchers, and understand Newtonian mechanics or
antenna theory, but wouldn’t know
how to “create” something if their life
depended on it.
W. D. Robins
In the commentary by Leslie Gordon, she made the blanket statement that “Any CAD jockey can do
‘design.’”
Now I may be new to the design and engineering field since
I have only been involved since
the 1970s, and I am not a degreed
engineer, but is she really serious? I have been trained in drafting, mathematics, science, physics,
multiple CAD formats, and came
up through in the school of hard
knocks. There are people trained
to use CAD (including engineers)
who can barely put two lines together, much less turn out designs
for equipment that can be manufactured, assembled, and actually
12
MACHINE DESIGN.com
Computerizing the profession
A host of readers didn’t take kindly to an
editorial that said “any” CAD operator can
do design. They didn’t appreciate being
compared to what they consider computerized draftsmen. Others felt the criticism of computer-based presentations
was somewhat off-base as well.
function properly upon completion. This statement is like saying
that any clerical secretary, trained
to put two complete sentences together can be a “Senior Editor” at
MACHINE DESIGN.
Steven D. Mueller
It’s a common complaint I have heard
at many engineering and software
trade shows and events: There should
be a clearer distinction between “designer” and “engineer.” Many complain what many so-called “designers” really do is just create a geometry.
Period. There is no understanding of
whether the device will actually work
in the real world. In contrast, the term
“engineering” or “engineer” implies
the necessary knowledge of the underlying physics or mechanics that
makes stuff tick and really work. —
Leslie Gordon
Don’t blame the software
Your recent editorial, (“PowerPoint
Can Kill,” June 14) says: “To most engineers, the idea of using graphs or
models to convey concepts comes
as second nature.” And you caution readers not to take PowerPoint
lightly. To this concern, I’d like to
add that the Internet can also negatively affect our thought processes.
For example, when we read print,
we generally comprehend and remember more than when we read
the same text online. It doesn’t
help that online articles are often
crammed with links that seem to
interfere more than enlighten.
The deep reading that comes
naturally with print can be a struggle online. That’s because printed
documents induce an attentiveness in which reading is more than
skimming. The computer, once our
AUGUST 23, 2012
servant, now becomes our master.
And online content may be less important than the medium itself. So,
while we enjoy the Internet’s benefits, we should question if we are
sacrificing our ability to read and
think effectively.
Ray Herzog
I am old enough to remember
when engineers effectively communicated long before there was
such a thing as PowerPoint. If you
were lucky, you had an overhead
projector for your meetings. More
frequently, you used a chalk board.
It may sound primitive, but writing
out your ideas and logic this way
forced you to focus only on essential points and think through your
presentation beforehand. It seems
the problem with PowerPoint is
that it lets speakers get by without
this sort of thoughtfulness.
And although I agree with you
that too many presentations are
just plain bad, PowerPoint is just
the tool. I do finite-element analysis for a living, so the software is
a necessity. I have not found any
other media tool that lets me show
people what is going on with their
parts. But the main problem is not
the tool, but the desire to automatize and oversimplify every task.
LETTERS TO THE EDITOR
Please include your name, address, and
daytime phone number. Letters may
be edited for brevity and to focus on
essential points.
Mail: Letters, MACHINE DESIGN,
1300 E. 9th St., Cleveland, OH 441141503, Fax: 216-621-8469
E-mail, Editorial:
[email protected]
RS# 111
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LETTERS
It seems our motto these days is,
“The less thinking, the better.”
Carlos Gutierrez
As a frequent (and hopefully effective) user of bullet points, I want to
dispel the notion that all bulleted
lists are signs of intellectual laziness. They are not. A good bullet
list can actually be the result of
intellectual rigor. But it’s true that
bad bullet lists result from the intellectual laziness you mentioned
or some other intellectual shortcoming. But please don’t blame
the bullets. And let’s make sure not
to blame Powerpoint either.
I do appreciate that the editorial
brings attention to the hazards of
poor slides. But again, lets make
sure to understand that poor slides
come from poor communicators.
Placing a pen in the hand of a poor
communicator would likely result
in a technical paper just as bad as
their PowerPoints. If one cannot
Correction
The June 14 arti10,000
cle, “Energy-EffiEnergy savings
cient Hydraulics
Slash Operating 2,000
41.4%
2.2 kW
33.1%
8.4 kW
Costs,” contained
an incorrect
5,000
graphic related
to energy con- 1,000 Variable- Constant- Variable- Constantsumption on inspeed
speed
speed
speed
pump
pump
pump
pump
jection-molding
machines. The
1.3 kW
5.6 kW
correct version,
0
0
50-ton,
160-ton,
shown here,
30-sec cycle time
15-sec cycle time
i n d i c a te s t h at
replacing constant-speed, electrohydraulic variable-displacement pumps with variable-speed pump drives cuts energy consumption well in excess of 30%.
create an organized bullet list
(which is much like the outline for
a paper), how can one expect to
create an organized paper?
The example of NASA’s exces-
!"#
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RS# 112
MACHINE DESIGN.com
AUGUST 23, 2012
sive use of Powerpoint in lieu of
technical papers is truly astoundi n g, a n d h o p e f u l l y s o m e o n e
learned a good lesson.
Ralph Terow
#!
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14
Comparing energy consumption
Injection-molding machines
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E-5157
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RS# 113
SCANNING FOR IDEAS
Edited by Stephen J. Mraz
Machine inserts
different-sized pins
in the same assembly
Micrometer-style
adjustments control
insertion depth
For high-volume jobs, it’s easy to
justify the cost of an automated
pin inserter. Automation
improves consistency of
installation and efficiency
while cutting costs
and scrap. But for lowvolume tasks, or jobs
that require different-size
pins, it has not always
been easy to justify the
cost of buying several different machines. To solve
that problem, engineers
at Spirol International
Corp., Danielson, Conn.
(www.spirol.com), developed the Model CR Combination Installation Machine.
It can install three completely difThree pin
ferent size pins in the same or three
orientation
different assemblies. The modular
heads; one for
each pin size
machine features separate vibratory
feeders and orientation heads for the
three different pins. And there are
three interchangeable fixture nests,
one for each pinning application.
Interchangeable
fixture nests
Each nest has a centrally located
dowel pin that aligns the fixture to
the pin-exit bushing. Precise dowel
holes are machined into the base
plate and lined up with each pinorientation head. A single bolt
secures the fixture while in use.
Each fixture is number
coded, making it easy for operators to ensure the right one is
loaded. When a pinning operation is completed, the operator reSolid-state
moves the fixture, installs the next,
microprocessor controls
and puts the selector switch in the
corresponding position to begin the
next pinning operation. The machine
can also be retooled with different
feeder-orientation heads and
r
formation via ou
Request free in Web site at
fixture combinations.
ice
rv
Se
er
ad
Re
RS# 401
m/rsc
hinedesign.co
ww w.mac
16
MACHINE DESIGN.com
AUGUST 23, 2012
Three feeders for
three different pin
sizes
Retracting
head simplifies
loading and
unloading parts
Hardened steel
bushings for long life
Antitie-down
dual optotouch
activation
For another article related
to specialty fasteners,
scan this code or go to:
http://machinedesign.
com/article/fastenersthat-maximize-assemblylife-1019
RS# 114
SCANNING FOR IDEAS
Pneumatic actuator
handles
linear and swiveling motion
Two types of cushioning available:
hydraulic shock absorber or flexible
cushioning elements
Allen key can adjust end
position once locknut is
loosened
Proximity sensors
also detect linear
position
Graduated scale makes it easy to
preset required angle
Swivel position determined
using proximity sensors
mounted on braking
subsystem
Swivel angle detected
using magnet in
braking lever
Engineers at Festo Corp.,
Hauppauge, N. Y. (www.festo.com/
us), combined the company’s standard DNC cylinder with its DSM-B
semirotary actuator to create a
pneumatic swivel/linear drive unit,
the DSL-B. The ready-to-install unit is
available in sizes from 16 to 40 mm
with strokes up to 200 mm, and both
swivel and linear motion can be controlled individually or simultaneously.
18
MACHINE DESIGN.com
The unit’s sturdy ball-bearing guide
lets it absorb relatively high levels of
torque. The swivel angle can be set
anywhere from 0 to 270°. Mechanical
gearing between the braking element and swivel module prevents
movement of the brake under load.
And a recirculating ball-bearing guide
contributes to precision, backlash-free
swiveling, and helps resist torque loads
during linear motion.
RS# 402
AUGUST 23, 2012
Flexible
mounting
surface
.PDF 
101 
265 
105 
