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Tài liệu Machine design, tập 84, số 01, 2012

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January 19, 2012 A Penton Media Publication Tune in to EngineeringTV.com Box-beam tracks make rides thrilling page 20 A NEW TYPE OF THREADED INSERT, page 50 POWERING UP OVER ETHERNET, page 58 HOW TO WORK WITH PLANETARY GEARS, page 62 Supplying reliable quality components for the automation and control industries www.altechcorp.com !*&15&798!*&11=+&89 ".251=:514&)=4:7 24)*1 &3)(-448*9-* '*89459.43+47 =4:73**)8   &(-.3.3,.3?)&=8 *89+47?5&798 7.(*)+742 -448*+742 ).A*7*392&9*7.&18 .3(1:).3," =143 *17.3 $ #  &1:2.3:2 &3)'7&88 3/*(9.43 41).3,.3?)&=8 *89+47?5&798 7.(*)+742 -448*+742 -:3)7*)84+ *3,.3**7.3, ,7&)*7*8.38 .3(1:).3,  41=5745=1*3* "  (*9&1 # 41=(&7'43&9* =143 41=&2.)* &3)  "!!&"% %"  "!  -448* 2&(-.3.3,47.3/*(9.43 241).3,<-.(-*;*7.8'*89+47=4:7 574/*(9$514&)=4:724)*1&3) 7*(*.;*&3&:942&9*).39*7&(9.;* 6:49*.3-4:78 3(*&5574;*)4:7 (1:89*7(425:9.3,9*(-3414,=&3) &:942&9*)2&3:+&(9:7.3,8=89*28 <.11)*1.;*77*&15&798:8.3,7*&1 2&9*7.&18.3&81.991*&843*)&= 3)9-&989-*7*&18947= @ 7494 &'83("  *79.>*) #"#  $!"! "#  " :73*<*89)*8.,3&.).8&(4410&1*.)4(=(1* 9-&98-4<89-**A*(94+2&9*7.&1843>3.8-*8 %.8.9  "! 94)&=&3) 7*6:*89=4:7+7** 7494,&2.39*7(4)*  &11   47;.8.9  "! RS# 101             2 +&8       9:8!     /        "   ; #          !   " "  #   #      $ % &&'(  )  *      #  +  ,& - &  !  &  .&   /  0  1  2  ) 3 % ,!  4.56 2    ..   #   7            "      2 '&&&   9<:&    ) !"     #$%$&' ( 2 8&&&      9+,! 2  ,&&.      9<+8                                      ! " #  $%$ ! "&       RS# 102         VOLUME 84 ISSUE 1 JANUARY 19, 2012 FASTENING & JOINING A threaded insert TOUGH ENOUGH Authored by: Jason Deters Senior Engineer Process & Technology Development General Dynamics Land Systems Sterling Heights, Mich.. for the Marines Fredserts give engineers a new way to put bolts in soft metal. FEATURES tracks let 20 Box-shaped mega-coasters soar High forces and extreme speeds made possible by stronger and smoother box-shaped rails. In search of an insert The design team wanted to use threaded inserts, a common practice when putting bolts in soft metals like aluminum and magnesium. Inserts, usually made of a tough metal like stainless steel, are installed into pretapped holes and permanently locked in place. Their interior threads give a strong, wear-resistant interface to install bolts into. Although engineers have a few basic types of threaded inserts to choose from, including key-locking, ring-locking, and helical-spring, none met the U. S. Marine Corps demands. For example, if a conventional insert needs to be MACHINE Design.com Resources: Fredsert offerings and videos, www. fredsert.com General Dynamics Land Systems, www. fredserts.com Miller Precision Industries, www. millerprecision.com For more info on the Expeditionary Fighting Vehicle scan this code or go to: http:// machinedesign. com/article/ marines-geta-new-assaultvehicle-1211 Engineers at General Dynamics Land Systems, Sterling Heights, Mich., faced a challenge when designing the Expeditionary Fighting Vehicle for the U. S. Marine Corps. The amphibious combat craft needed to be made mostly of a lightweight aluminum alloy so that it would meet its mission objectives. But aluminum is relatively soft, and fasteners used to attach components to the aluminum frame needed to satisfy several requirements. They had to be lightweight, create watertight seals, lock in place solidly, resist extreme vibrations and shock, and withstand extended exposure to saltwater. The Marines also wanted be able to remove and replace the fasteners in the field. 50 Edited by Stephen J. Mraz [email protected] Fredsert threaded inserts have been used by General Dynamics Land Systems, Sterling Heights, Mich., on several military vehicles, including the Expeditionary Fighting Vehicle, the Future Combat System for the Army, and the Joint Light Tactical Vehicle for the Army, Fredserts also went into several thousand Humvees when they were upgraded. Here are several female Fredserts installed in the sidewall of a military vehicle. The four oval drive slots on the head of the Fredsert mate with drive lugs on the tool used to install Fredserts. removed for any reason, it must be drilled out. This risks damaging the hole in the parent material. Plus, drilling can be clumsy and difficult if the insert is not easily accessible. Another limitation is that inserts typically cannot create air and watertight seals without using a thread-locking compound. And even when thread-locking compounds are used, many inserts don’t offer ‘blind’ internal threads, so there is still a leak path. And finally, there’s a limited range of standard threaded inserts on the market, and custom lengths or materials are typically accompanied by high prices and long lead times. JANUARY 19, 2012 This lack of flexibility often means engineers must alter their designs to accommodate available insert sizes or material options. Faced with requirements it could not meet with commercially available threaded inserts, General Dynamics began internal design and development of an insert that would do the job without adding cost. Led by a talented and now-retired tool engineer named Fred Wheeler, the team came up with the Fredsert after 12 months of development, testing, and redesign. Ultimately, more than 6,000 Fredserts were installed on each Expeditionary Fighting Vehicle, and Fredserts have been used on several other General Dynamics vehicles and weapons, including the Mk 46 naval-gun turret, the Army’s Future Combat System and Joint Light Tactical Vehicles, the Navy’s Littoral Combat Ships built by Austal, Mobile, Ala., as well as more than 12,000 upgraded Humvees made by AM General, South Bend, Ind. Fredserts’ advantages A Fredsert combines a tapered thread profile, 100% thread engagement, cutting flutes, and a flanged head to create a friction fit with material compression to reliably lock it in place. External threads are slightly oversized compared to other inserts and tapered in certain areas so that they create a friction-fit when installed into the parent material (such as aluminum). And all of the Fredsert’s threads are engaged with the parent material, much like the way taps interface with threaded holes. Other inserts use standard bolt threads that end up with significantly less contact with the parent material in terms of surface area. The flanged head also helps in that it gets torqued down onto the parent material and contributes to the locking action. Fredserts are designed to exceed the tensile strength of bolts installed in them. In tests, bolts break before the JANUARY 19, 2012 50 44 How inventors can move from hopes and A “million-dollar” idea? dreams to reality and the marketplace. threaded insert tough 50 Aenough for the Marines MECHANICAL An inside look at Fredserts give engineers a new way to put bolts in soft metal. Planetary gearheads can improve machine performance and efficiency, and lower costs. But proper sizing is critical. Power-over58 Giving Ethernet some muscle As power-over-Ethernet applications expand, demands for even more power are following right along. Authored by: Howard Horn Product Manager Thomson Industries, Inc. Wood Dale, Ill. Edited by Kenneth J. Korane [email protected] 62 t1MBOFUBSZVOJUTXJUIIFMJDBMHFBST SBUIFSUIBO spur gears, have higher torque capacity and run quieter. t%JGGFSFOUNBOVGBDUVSFSTNFBTVSFBOESBUF CBDLMBTIJOEJGGFSFOUXBZT t4PGUXBSFUPPMTGPSTJ[JOHBOETFMFDUJPOMFU EFTJHOFOHJOFFSTRVJDLMZGJOEBOEDPNQBSF gearheads that suit an application. Micron Motioneering gearhead sizing tool, www.micronmotioneering.com Thomson Industries, www.thomsonlinear.com 62 Planetary gearheads can improve machine performance and efficiency and lower costs. But proper sizing is critical. Micron AquaTrue Planetary gearheads offer IP67 protection against harsh cleaning chemicals and high-pressure wash down. Key points: Resources: An inside look at planetary gears planetary gears MACHINE DESIGN.com Planetary gearheads are high-precision, motion-control devices that generate substantial torque for their size, have high torsional stiffness, and low backlash — making them suited for wide-ranging tasks. 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Also available are slim, right-angle designs to JANUARY 19, 2012 62 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 2 MACHINE DESIGN.com JANUARY 19, 2012 MACHINE Design.com 51 Worth a thousand words Sometimes lights and sounds are a better way to communicate! Our NEW modular stack lights from WERMA give you total choice and flexibility to create a free combination of optical and audible signal elements. The 70mm IP65-rated KS 71 series allows up to five elements per terminal base; the 50mm KS 50 IP54rated system supports up to four elements. Rugged construction and no-tools assembly means reliable operation and easy maintenance in applications such as machine tools, packaging machinery and conveyor systems. 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RS# 103 ON THE COVER DEPARTMENTS Box-shaped roller-coaster tracks at Six Flags Over Texas. 8 EDITORIAL How to ace an engineering job interview 10 EDITORIAL STAFF 12 LETTERS 16 SCANNING FOR IDEAS Efficiency lets smaller motors handle bigger jobs Overpressure valve protects lithium-ion battery packs 20 REPORTER’S NOTEBOOK 30 LOOKING BACK 36 COMMENTARY Time for engineers to think about unionizing? — Stephen J. Mraz 38 ADVANCED MANUFACTURING 40 BERKE ON SAFETY When machine operators slip and fall 42 VANTAGE POINT Agile product development and strong-form product management — Barry Jaruzelski, Richard Holman 69 ORR ON ENGINEERING Solving problems in context 70 SOFTWARE PRODUCTS 72 PRODUCT SPOTLIGHT Pumps & compressors 74 82 83 84 86 86 87 4 PRODUCTS BUSINESS INDEX AD INDEX DATA FILES CLASSIFIEDS BUSINESS STAFF BACKTALK MACHINE DESIGN.com For customized article reprints and permissions please contact: Penton Reprints, 1-888-858-8851, e-mail at [email protected] or visit pentonreprints.com. Editorial content is indexed in the Applied Science Technology Index, the Engineering Index, SciSearch and Research Alert. Microfilm copies available from National Archive Publishing Company (NAPC), 300 N. Zeeb Rd., P.O. Box 998, Ann Arbor, MI 48106-0998, Ph: 734-302-6500 or 800-420-NAPC (6272), extension 6578. Permission to photocopy is granted for users registered with the Copyright Clearance Center (CCC) Inc. to photocopy any article, with the exception of those for which separate ownership is indicated on the first page of the article, provided that the base fee of $1.25 per copy of the article, plus $.60 per page is paid to CCC, 222 Rosewood Dr., Danvers, MA 01923 (Code No. 0024-9114/12 $1.25 + .60). Subscription Policy: MACHINE DESIGN is circulated to research, development, and design engineers primarily engaged in the design and manufacture of machinery, electrical/electronic equipment, and mechanical equipment. To obtain a complimentary subscription see our Web page at submag.com/sub/ mn. For change of address fill out a new qualification form at submag.com/sub/mn. Printed in U.S.A., Copyright © 2012. Penton Media, Inc. All rights reserved. MACHINE DESIGN (ISSN 0024-9114) is published semimonthly except for a single issue in January, February, June, July, and December by Penton Media, Inc., 9800 Metcalf Ave., Overland Park, KS 66212. Paid subscriptions include issues 1-18. Issue No. 19 (OEM Handbook and Supplier Directory) is available at additional cost. Rates: U.S.: one year, $139; two years, $199;. Canada/Mexico: one year, $159; two years, $239; All other countries: one year, $199; two years, $299. Cost for back issues are U.S. $10.00 per copy plus tax, Canada $15.00 per issue plus tax, and Int’l $20.00 per issue. Product Locator, $50.00 plus tax. Prepaid subscription: Penton Media (MACHINE DESIGN), P.O. Box 2100, Skokie IL 60076-7800. Periodicals Postage Paid at Shawnee Mission, Kans., and at additional mailing offices. Can GST #R126431964. Canadian Post Publications Mail Agreement No.40612608. Canada return address: Pitney Bowes, P.O. Box 25542, London, Ont., N6C 6B2. Digital subscription rates: U.S.: one year, $69; two years, $99;. Canada/Mexico: one year, $79; two years, $119; All other countries: one year, $99; two years, $149. JANUARY 19, 2012 POSTMASTER: Send change of address notice to Customer Service, MACHINE DESIGN, P.O. Box 2100, Skokie, IL 60076-7800. Super Ion Air Knife™ Produces a laminar sheet of airÀow that Àoods an area or surface with static eliminating ions. Super Ion Air Wipe™ The uniform 360° ionized airstream neutralizes and cleans continuously moving surfaces. Prevent Shocks, Jamming, Tearing and Static Cling! 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Ion Air Jet™ Delivers a concentrated blast of ionized air prior to shrink wrapping, packaging and printing. ,,,-'%#   )# Ionizing Bar If you would like to discuss an application or request a catalog, contact: Eliminates static cling, dust attraction and jamming on paper, plastics and ¿ lm. RS# 104 $*)*'$$)""$)%#&'(( ''%*)($  11510 Goldcoast Drive*Cincinnati, Ohio*45249-1621*(800) 903-9247*fax: (513) 671-3363 E-mail: [email protected] *www.exair.com @exair www.exair.com/45/470.htm What’s new online machinedesign.com Understanding ac induction, servo, and permanent-magnet motors This new eBook from Leeson Electric provides an exhaustive technical overview of three major motor types with overlapping capabilities for sophisticated applications. The illustrated handbook is an essential reference for all engineers tasked with selecting motors for machinery. Topics include a technology overview; force, torque, and speed capabilities; limitations and performance challenges; and an explanation of where each motor type is most suitable and unsuitable. Get a copy at the eBooks section of http://machinedesign.com. Combating counterfeit electronics Some estimates say the global IT industry loses $100 billion in revenue to counterfeiters annually. Penton Media and Mouser Electronics assembled a group of experts at the Combating Counterfeit Electronics Workshop who discussed all aspects of the counterfeit electronic-parts problem. Panelists from major manufacturers, users, and test labs share their insight into this important industry topic. View the episode at www.engineeringtv.com/video/ Combating-Counterfeits-Workshop; Only-Engineering-TV-Videos. Power transmission for wind turbines EDITOR’S WEB PICKS Altra Wind Technology’s new Web site, www.AltraWind.com, covers power transmission and motion control in wind turbines. Sections include rotor, yaw, and blade-pitch brakes, shaft-locking devices, high-speed shaft couplings, and access hatch actuators. Each offers technical details to improve efficiency, productivity, safety, and reliability. 6 New forum on materials, adhesives The Fabrico Forum (www.fabricoforum. com) provides a focal point for information on selecting, bonding, and converting flexible materials. Design engineers who face challenges involving materials and adhesives can ask questions and connect with industry experts and colleagues working in the same product areas. Mobile apps offer electrical expertise The PowerEdge mobile app from Eaton lets users access electrical-powermanagement catalogs, technical data, videos, and training. The free app for iPhones and iPads reportedly helps improve the reliability, efficiency, and safety of electrical systems. Learn more at http://poweredge.eaton.com. MACHINE DESIGN.com JANUARY 19, 2012 DESIGN COMPETITIONS 5,000 Euro prize The igus vector award competition rewards innovative cable-carrier designs. The worldwide competition highlights how cable carriers are used to solve challenging load, speed, and travel problems. Deadline for submissions is February 28. For more information, visit www.vector-award.com. Best in plastics The second International Plastics Design Competition, sponsored by the Plastics Industry Trade Assn., is underway. Entries for products or components can be submitted by February 1, in any of 18 end-use categories from agriculture to transportation. Winners will be displayed at NPE 2012. Find more details at www.plasticsdesign.org. Watch recorded Webinars on industrial control topics View free prerecorded Webinars on the most popular topics at your convenience at www. automationtalk.com. MOTION CONTROL This 40-minute session demonstrates how to use motion control with AutomationDirect’s stepper motors and Micro PLCs. See what to purchase and how to configure the components; watch live demos and discussions on real-world applications. PROCESS CONTROL This 40-min presentation discusses process control, and the products AutomationDirect offers that are useful in those applications. Learn about devices that can sense temperature and pressure; control devices such as temperature controllers and PLCs that accomplish PID control; signal conditioning; and timer relays that are useful in this area of automation control. PNEUMATICS This 40-min session covers the NITRA pneumatic products AutomationDirect offers. The line now includes stainless-steel cylinders, filters, regulators, lubricators, solenoid valves, position switches, tubing, and fittings. See working demos and customer examples. Visit www.automationtalk.com to view Webinars and check the schedule for upcoming presentations. DĞĚŝĐĂůĞƋƵŝƉŵĞŶƚƌĞƋƵŝƌĞƐŚŝŐŚƉĞƌĨŽƌŵĂŶĐĞŵŽƚŽƌƐ͘DŽŽŐ^ŝůĞŶĐĞƌΡƐĞƌŝĞƐ ďƌƵƐŚůĞƐƐ  ŵŽƚŽƌƐ ŽĨĨĞƌ ƵŶŝƋƵĞ ĚĞƐŝŐŶƐ ƚŚĂƚ ĚĞůŝǀĞƌ ƌĞƐƵůƚƐ͘  hůƚƌĂͲƋƵŝĞƚ ĨƵŶĐƟŽŶĂůŝƚLJ͕ ƐŵŽŽƚŚ ŽƉĞƌĂƟŽŶ Ăƚ ǀĂƌŝŽƵƐ ƐƉĞĞĚƐ ĂŶĚ ƚŚĞ ĂĚǀĂŶƚĂŐĞ ŽĨ ŚŝŐŚ ƚŽƌƋƵĞĂƚĂůŽǁĐŽƐƚ͘ >ĞĂƌŶŵŽƌĞĂďŽƵƚDŽŽŐ͛ƐƐŽůƵƟŽŶƐĨŽƌmedical centrifugesĂŶĚŽƚŚĞƌŵĞĚŝĐĂů ĚĞǀŝĐĞƐ͘^ƚĂŶĚĂƌĚĂŶĚĐƵƐƚŽŵŵŽƚŽƌŵŽĚĞůƐĂƌĞĂǀĂŝůĂďůĞǁŝƚŚŽƉƟŽŶƐ͘ŽŶƚĂĐƚ ƵƐƚŽĚŝƐĐƵƐƐLJŽƵƌĂƉƉůŝĐĂƟŽŶ͘  Looking for more? ^ĐĂŶƚŽǀŝĞǁŵŽƚŽƌƐƉĞĐŝĮĐĂƟŽŶƐ͘ Brushless Motor Features: ͻ ZƵŐŐĞĚƉĂĐŬĂŐĞ ͻ ŽŵƉĂĐƚƐŝnjĞ ͻ ,ŝŐŚƌĞůŝĂďŝůŝƚLJ ͻ >ŽŶŐͲůŝĨĞ ͻ /WϲϱƌĂƚĞĚ DŽƟŽŶdĞĐŚŶŽůŽŐLJͮ&ŝďĞƌKƉƟĐƐͮůĞĐƚƌŽŶŝĐ^LJƐƚĞŵƐ нϭͲϱϰϬͲϱϱϮͲϯϬϭϭϴϬϬͲϯϯϲͲϮϭϭϮ;h^ͿŵĐŐΛŵŽŽŐ͘ĐŽŵ www.moog.com/components RS# 106 EDITORIAL How to ace an engineering job interview The economic recession has abated somewhat, and hiring is on the upswing. Now you’re more likely to read about the travails of those interviewing for employment rather than people downsized out of jobs. In that regard, it looks as though the new trend in job interviews is to ask brain-teaser-type questions. The practice seems to have been popularized by hiring managers at Google. According to William Poundstone, author of a book called, Are you smart enough to work at Google?, that company relies on such off-beat interview questions as a way of sifting out people who won’t fit into its culture. You might wonder what kind of culture a company has if it hires people based on how they answer a question like, “You are shrunk to the height of a nickel and thrown into a blender. Your mass is reduced so that your density is the same as usual. The blades start moving in 60 seconds. What do you do?” Apparently Googlites are looking for inventive answers. (One of the best is supposedly to recognize that small creatures are stronger in proportion to their weight and that you can probably just jump out of the blender.) Another company that apparently buys into brain-teaser interview questions is Tesla Motors. Tesla interviewees reporting on the Glassdoor.com site say the EV maker mixes brain-teasers with queries about fundamental physics, including: Why do letters in mirrors reverse horizontally and not vertically? You’re in a row boat, which is in a large tank filled with water. You have an anchor on board and throw it overboard. (The chain is long enough so the anchor rests completely on the bottom of the tank). Does the water level in the tank rise or fall? Though riddlelike interview questions get a lot of attention, the more important part of a hiring process is probably the questions applicants answer that resemble the work they’ll eventually perform. People applying for programming positions at Google, for example, must write code during their interviews. But at any engineering company, sometimes even work-related questions can seem a bit off the wall. A friend of mine describes an incident during one such interview at a control-systems engineering firm: “I extolled my past experience and credentials, but I could tell the guy doing the interview wasn’t convinced. All of a sudden he eyes me suspiciously and says, ‘What’s the integral of 1 over x?’ To my extreme surprise I seemed to recall it was log(x), and though unsure I blurted out my answer. He brightened measurably and said, ‘That’s the question I use to separate out the real engineers!’ I got the job, even though I could not have worked a control-theory integral problem to save my soul.” The fallacy with questions that demand mental gymnastics is that they don’t say much about how the applicant will perform day-to-day work. “What you see is not always what you get,” says Dean Stamoulis, head of the Global Executive Assessment Practice for Russell Reynolds Associates in New York City. He also notes that some of the best candidates don’t make good first impressions, and it’s important to look deeper than an initial perception. Finally, he advises that sometimes what is not said in an interview is important as well. “If an interviewee doesn’t mention others he or she led and name key contributors to past successes, that might indicate he or she is taking credit for others’ work and ideas.” — Leland Teschler, Editor RS# 107 JANUARY 19, 2012 The round thing has to go into the rectangular thing. #OMPACT#ENTRIFUGAL-ODULESWITHTHENEWRadiCalIMPELLERS s3PACESAVINGPACKAGEDAIRMOVERSWITHIMPELLERDIAMETERSMM TOMM s-AXIMUM#&-ORSTATICPRESSURE s RadiCalIMPELLERDESIGNIMPROVESAERODYNAMICEFlCIENCYANDACOUSTICS s!VAILABLEWITH03#MOTORSORENERGYLEAN%#MOTORS OR6!# s%#MODELOPTIONSFOR SPEEDORFULLYSPEEDCONTROLLABLE s!NYMOUNTINGPOSITIONANDCOMPLETELYMAINTENANCEFREE &ORMOREINFORMATION CHECKWITHOUR!PPLICATION%NGINEERSAT   #OMEVISITUSATBOOTHAT!(2IN#HICAGO ON*ANUARYRD TH INFOEBMPAPSTUS2ADI#AL The engineer’s choice RS# 108 Control Solutions That Actually Give You EDITORIAL STAFF ...CONTROL! VIC offers the ideal solution for OEMs looking for a panel manufacturing resource with extensive knowledge of North American standard. Whether it be a single machine control panel, an OEM looking to add some touch screen “sales dazzle” to their machine controls, or complete industrial control systems, VIC goes the extra distance to understand your market and machinery to design and produce controls that will optimize the performance of your equipment. • System-wide communication, process control and monitoring • Powerful solutions for product and process integration - OEMs anel Builder P r u e Yo ator! Let us BSystems Integr and Leland E. Teschler, Editor, [email protected] Kenneth J. Korane, Managing Editor, [email protected] SENIOR EDITORS Leslie Gordon, Stephen J. Mraz AUTOMOTIVE & NEWS FEATURES Stephen J. Mraz, [email protected] CAD/CAM Leslie Gordon, [email protected] ELECTRICAL, ELECTRONICS AY`_V+$$')'"'!(!•gZTT`_ec`]dT`^ Robert J. Repas, Jr., [email protected] RS# 109 FASTENING, JOINING MEETING YOUR NEEDS FOR PRECISION STAINLESS STEEL • Tubing • Bar Stock • Custom Fabrication • Custom Sizes & Shapes • Precision Cut-to-length • Laser Welding & Cutting • Swiss Screw Machining • CNC and Much More! Jessica Shapiro, [email protected] FLUID POWER Kenneth J. Korane, [email protected] MANUFACTURING Leslie Gordon, [email protected] Kenneth J. Korane, [email protected] MATERIALS Jessica Shapiro, [email protected] MECHANICAL g ervin e c en s s be aerospa sa h Eagle edical, ch indu the m high-te 982. s r a and since 1 ye tries ISO 9001 ISO 13485 AS 9100 Kenneth J. Korane, [email protected] Jessica Shapiro, [email protected] EDITORIAL PRODUCTION Denise Greco, Editorial Production Manager Randall L. Rubenking, Art Director EAGLE STAINLESS Tube & Fabrication Inc. 10 Discovery Way Franklin Massachusetts phone 800-528-8650 fax. 800-520-1954 www.eagletube.com 10 RS# 110 MACHINE DESIGN.com JANUARY 19, 2012 1300 E. 9th St. Cleveland, OH 44114-1503 RS# 111 LETTERS Nontraining Your recent editorial (“Training that Doesn’t Train Anyone,” Nov. 3) struck a spark. I work with young people by taking promising ones into my shop for a few weeks to train them on a variety of shop practices, including gear cutting, lathe and mill operation, grinding, metallurgy, heat treating, welding, CAD, and inspection. My shop is more complete than any college shop I’ve seen. The end result is that after three weeks, the student usually lands a job at $17/hr with full benefits. One recent “graduate” phoned and told me that after two weeks he’s now manager/foreman over the grinding department in his company. He was a high-school graduate with fairly good grades and had graduated from a diesel-mechanics school, and couldn’t find a job. It seems I know the skills that companies need but can’t find or won’t train people for. Humility prevents me from saying I must be a genius compared to the people the government has working for them as “educators.” Oh, and I do it for nothing. Steve Tuttle At the beginning of your editorial, you mention CAD software vendors offering training on their software to anyone who has fallen victim to an economy that the amazing prodigies in our government are so dedicated to improving. I hope those vendors are also training those people on what makes a good mechanical drawing or 3D part model. I once worked at a company that evidently hired designers and drafters based on the simple fact that they had once double-clicked an AutoCAD icon. Most of them were fired or quit without notice after a brief time. Learning a piece of software and learning a trade may go hand in hand, but one does not equal the other. For example, I am knowledgeable about spreadsheets, but that doesn’t mean you want me doing your bookkeeping. Joel W Suffridge 12 MACHINE DESIGN.com Who stole our innovation? Thanks for your editorial on the hurdles to innovation (“R&D Doesn’t Mean Innovation,” Oct. 6). I agree with you that patent trolls hinder innovation, but the cause is not the patent system, nor is the solution to eliminate it. The patent system is necessary to sustain long-term R&D efforts. If a company spends millions of dollars developing and marketing a product, they need time to recoup their investment to stay in business as well as fund future R&D projects. As I see it, patent trolls are the real cause of our stifled innovation, and we should work to eliminate them. One way to get rid of them might be to require that patent holders use the technology in their patent applications in real products that are released to the market. The patentpending technology should not only be used for production, but also have sales volumes that let manufacturers at least break even, say at the end of the third year. Under such requirements, approval of the patent application would be tied to the benefits the patent offers to the economy. This solution should stop patent trolling and leave the real work to those serious about bringing innovations to society. Eugene Kim In the late 80s, I worked at a tool house which won a contract to build a family of dies that were to be used to fabricate heat exchangers for home gas furnaces. I traveled to the plant where the tools would JANUARY 19, 2012 be used to go over requirements. While there, I was given a plant tour, including the “Research Lab.” I was shocked to find that all of the research consisted of dismantling competitors’ furnaces to see if there were any ideas worth stealing. My boss and I had a good laugh about this company’s research. Fast forward to late 90s with another company and now I was involved with dies to fabricate components for home air conditioners. Again a plant tour included the research lab. This company’s research consisted of studying competitors A/C units looking for ways to improve their own products. I must conclude that either the two companies I visited were the only two dishonest HVAC firms or the whole industry does nothing more than pirate from competition. There must be a HVAC innovator out there somewhere, but I sure did not see the evidence. Ralph L. Wirtel When will we realize as a society that throwing money at a problem doesn’t ensure success? We need not look any further than public education to see that. Many school districts that spend the most per student are among the lowest performers. More to your point, what I’ve seen over the past 20 years is a steadily growing myopia among decision makers both in industry and government when it comes to innovation and R&D. About two-thirds of my career has been in military-funded R&D and the other third in commer- Name Hector Guajardo Betancourt, Certified LabVIEW Architect Job Title Automated Test and Control Engineer Area of Expertise Manufacturing Test LabVIEW Helped Me Reduce test time by more than 10X Latest Project Building a vision-based inspection system for washing machine drums NI LabVIEW LabVIEW makes me better because I can deliver multiple on time, on spec, and on budget >> Find out how LabVIEW can make you better at ni.com/labview/better RS# 112 ©2011 National Instruments. All rights reserved. LabVIEW, National Instruments, NI, and ni.com are trademarks of National Instruments. Other product and company names listed are trademarks or trade names of their respective companies. 01197 800 453 6202 LETTERS cial product development. The Commercial-Off-The-Shelf revolution in government acquisition has much to do with shorter term thinking — it emphasizes evolutionary (development) advances over revolutionary (research) ones. Most government program managers would prefer to modify a commercial device or system to military purposes rather than come up with a truly new idea and product. COTS reduces development time, cost, and, most importantly these days, risk. Yet, the commercial sector doesn’t seem to fare better. Managers seem to have mastered the art of putting the “no” in innovation. There are so many layers and gatekeepers in large organizations that out-of-the-box ideas are easily smothered. Those that aren’t smothered often get delayed for such a long time that by the time they garner support, the need for them or the market opportunity has long since passed. One of the main points Dr. Michael Hammer made in his 1993 book, Reengineering the Corporation, still rings true today; hierarchical structures get in the way of change. Hierarchical structures inherently have a lot of activities going on that do not add value to the company’s products or services. The primary objective of a bureaucracy is self-preservation, the second is growth. I’ve come to the conclusion that there is not much an individual or even a group of individuals at the working level can do aside from moving to a smaller company or starting one of their own, Yet, many technological advances require a substantial investment in infrastructure that individuals or small companies do not command. For example, if someone comes up with a new way to make steel that uses 20% less energy, where does she or he go if the company they work for isn’t interested because the investment it requires would siphon funds from another project with substantially less risk but also fewer benefits? Finally, I don’t necessarily agree with the “no patents” idea. People should be allowed to reap the benefits of their ideas. That is the purpose of the patent system. Yet, your point is well taken; the system gets abused by people with little or no moral conviction other than making as much money as they can while expending as little real effort as possible. One counter to the patent trolls is the use of trade secrets. This is especially effective with processes used to make generic products when the result cannot be differentiated in the final product. Yet, they can be effective in differentiable products. Consider Coca-Cola and Heinz ketchup; neither has patented their formulations (which would’ve run out decades ago) but, they have viable businesses based on trade secrets. Christopher Perhala M I L L I O N S O F O P T I O N S WASHERS )*"%#+"(, FREE CATALOG  #-") *"(#%) Call 1-888-WASHERS     .)%") '$"()!'&   .    14 RS# 113 MACHINE DESIGN.com WWW.BOKERS.COM/MD JANUARY 19, 2012 RS# 114 A n atomy of the HUCK BOBTAIL ® Strength is in its DNA. Engineered for the maximum level of reliability, the BobTail® HuckBolt® offers 5 to 10 times the fatigue strength of conventional nuts and bolts. Its shallow thread and large root radius increase fatigue strength. And full metal-tometal contact between the collar wall and the bolt threads eliminates the gap that you find with ordinary nuts and bolts; the kind of gap that can lead to loosening under vibration intensive conditions. Ultimate strength and vibration resistance. It’s engineered into every BobTail HuckBolt. FULL METAL-TO-METAL CONTACT ELIMINATES GAPS TRANSVERSE VIBRATION COMPARISON CLAMP (LBF-THOUSANDS) 25 Once vibration begins, clamp load quickly decays with nuts and bolts, while it holds constant with the BobTail . 20 BOBTAIL 15 10 NUT 5 0 0 50 AND 100 time (SECONDS) ® afsindustrial.com/bobtail 800-388-4825 RS# 115 BOLT 150 200 250 SCANNING FOR IDEAS Edited by Stephen J. Mraz Efficiency lets smaller motors handle bigger jobs Platinum e Motors from Leeson Electric Corp., Grafton, Wis. (www.leeson. com), use a range of advanced features that increase their efficiency and power density, letting customers get more power out of smaller motors. The permanent-magnet ac motors are also built to CI Severe Duty standards, making them suitable for use in harsh environments. Platinum e motors use a different type of rotor than most other induction motors. In squirrel-cage motors, current is induced into the rotor from the field (stator) through an air gap, Conduit box and conducted through a includes a terminal bar of aluminum or other block conductive material. These bars are most often die cast and mounted in the rotor laminations’ slots. In Platinum e motors, the rotor itself contains permanent-magnet material, which is surface mounted to the rotor lamination stack or Permanentembedded within the laminamagnet motor tions. In both cases, electrical power is supplied through the stator windings. The motors use concentrated windings, essentially a bobbin winding. Therefore, unlike distributed windings used in induction motors, there are no shared slots. This eliminates the potential for phase-to-phase shorts. The concentrated windings also mean shorter end turns. This reduces waste and makes room in the housing for more active material, contributing to higher power density (end turns do nothing to generate torque). IP55 protection The motors carry the company’s inverter-rated insulation against the system (IRIS), which protects against voltage spikes induced by elements variable-frequency drives. It includes specially formed phase insulation; cushioned and sleeved connections from the leads all the way into the turns; and deep-penetrating, nonhygroscopic, high-temperature varnish, along with second-generation spike-resistant magnet wire. Motors are available with the common ac-induction-motor speeds of 3,600, 1,800, and 1,200 rpm. They are rated for variable or constant-torque to 20:1 without feedback in open-loop operation or 2,000:1 in close-loop operation (with encoder). RS# 401 16 MACHINE Design.com JANUARY 19, 2012 IRIS insulation Fractional motors feature rolled-steel construction. Integral motors use cast-iron construction. Bearing for 180 frames and larger can be greased r formation via ou Request free in Web site at ice rv Se er ad Re c design.com/rs ww w.machine RS# 116 SCANNING FOR IDEAS Overpressure valve protects lithium-ion battery packs Lithium-ion battery packs, which are becoming more common in electric vehicles, energy-storage, network back-up devices, and other industrial applications, can become overpressured if gas accumulates inside. This can be dangerous and risks damaging equipment. To prevent such overpressurizations, engineers at Freudenberg Sealing Technologies in Wienheim, Germany, developed a simple pressure-control valve which is now offered at Freudenberg-NOK Sealing Technologies, Plymouth, Mich. (www.freudenberg-nok.com). The lightweight valve uses an engineered EPDM seal, which opens when pressure inside the battery pack exceeds a specific limit, but there is no loose hardware during such releases because the valve is permanently tethered to the battery pack. The valve must be manually replaced to reseal the battery pack. The valve can also be manually opened, which can be handy when shipping battery packs by air. Otherwise, pressure changes during ascents and descents could damage the battery housing. And if a battery fails and causes overpressurization, the valve can be reset to protect interior components during transport to a recycling center. The overpressure valve is not adjustable. Its fixed pressure release/ open point is designed into the geometry of the valve. However, valves can be developed to meet customerspecific requirements. The EPDM seal resists leaking and swelling and withstands temperatures from –40 to 80°C. Users can add components which will add protection against impacts from stones and other road debris or let it survive industrial cleanings. RS# 402 18 MACHINE Design.com JANUARY 19, 2012 Overpressure valve swings open to relieve pressure Fixing element Flexible EPDM serves as a hinge
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