Machine design, tập 84, số 17, 2012

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Machine design, tập 84, số 17, 2012

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November 8, 2012 A Penton Media Publication Tune in to EngineeringTV.com HOW HOT RODDERS SOUP UP ELECTRIC MOTORS, page 20 HOW TO MAKE CAM FOLLOWERS IN PLASTIC, page 38 HOW TO MAKE PLASTIC OUT OF PLANTS, page 46 HOW TO DODGE DANGER WITH AIR LOGIC, page 60 Microhydraulics Macro capabilities So much reliability and performance, in so little space Creating high-performance ow control on a micro scale has been The Lee Companys exclusive focus for more than 50 years And its been a successful mission, as evidenced by thousands of applied Lee Microhydraulics designs ranging from less than 0.10 in to 1.00 in in diameter, and 0.1 to 68 grams, for operating pressures to 8,000 psi But small size and light weight are just the beginning.Theres also absolute reliability built into every Lee component through 100 % testing and inspection Zero defects Its a production benchmark that has enabled Lee to meet demanding application needs in all sorts of industries Aerospace, medical instrumentation, automotive, machine tools and oil drilling, to name a few The innovative problem solvers We dont just satisfy requirements We also solve problems whether by simple modication, or ground-zero design engineering The Lee Company is the worlds most capable and proven source for hydraulic-component innovation And weve documented this claim in extensive detail with the Lee Technical Hydraulic Handbook An invaluable reference, the Lee handbook contains essential data on the entire Microhydraulics product line, which includes: Lee Shuttle Valves Detented, spring-biased, inverse, loose ball and zero leak shuttle valves from 50-700 Lohms Lee Safety Screens Best protection for critical system elements 75 to 500 micron hole size Pressures to 7,500 psid Lee Pri Pressure relief valves in insert form 50 to 400 Lohm capacity 20 to 5,400 psid cracking pressures Lee Directional Flow Control 40 to 20,000 Lohms in metered direction 12 to 470 Lohms in free-ow direction Lee Restrictors Single and multi-orice restrictors 200 to 2.2 million Lohms Lee Shuttle Valve Shown actual size Designed to isolate the normal from the emergency hydraulic system So small, it ts right into the head of an actuator Lee Plugs The best way to seal drilled holes to 32,000 psi No O-rings, threads or sealants required Lee Cheks All-metal and zero-leak check valves to 400 Lohms Innovation in miniature Essential reading for designers of hydraulic systems Send for your free copy Westbrook The Lee Company Pettipaug Rd, Westbrook CT 06498-0424 860-399-6281 Fax: 860-399-2270 1-800-LEE PLUG www.TheLeeCo.com Gerrards Cross RS# 101 Paris Frankfurt Milan High Performance Pressure Instruments New! Metric Models High Accuracy Transducers Micro-Machined Silicon for Pressure Measurement 5-Point Agency Traceable Calibration Included Metric Pressure Ranges PXM409 Series 10 mV/V, to 10 Vdc, or to 20 mA Outputs Starts at $475 Gauge, Compound Gauge, Absolute, Vacuum and Barometric Pressure Ranges Available Welded Stainless Steel Construction 316 Stainless Steel Wetted Parts Visit omega.com/pxm409 Handheld Digital Manometer for Differential, Gage and Absolute Pressure High-Accuracy Pressure Calibrators Visit omega.com/pcl341 PCL341 Series Starts at $1495 Very High Accuracy Digital Pressure Gauge 316 SS Body, Analog Output and Optional Wireless Transmitter Visit omega.com/dpg409 HHP240 Series Starts at $408 DPG409 Series Starts at $695 Visit omega.com/hhp240 omega.com đ Because of transmission frequency regulations, these wireless products may only be used in the United States, Canada and Europe đ  RS# 102 â COPYRIGHT 2012 OMEGA ENGINEERING, INC ALL RIGHTS RESERVED VOLUME 84 ISSUE 17 NOVEMBER 8, 2012 MOTION CONTROL Rollers with polymer bearing surfaces work with aluminum rails, which cost far less than groundhardened-steel versions How to GET BETTER MOTION with plastic parts Nylon 12: The plastic of choice Polymer bearing surfaces resist wear, dont need maintenance, and can run surprisingly fast FEATURES to get better motion 38 How with plastic parts Rollers, cam followers, and other components used for moving parts can make good use of polymers to increase speeds, reduce wear, and resist chemicals and harsh environments Theyre also quieter than metal components The polymer advantage Many engineers still believe that heavily loaded applications need metal rollers and cam followers They are unaware that polymer bearing surfaces withstand enormous forces if designed properly At Intech Power Core, Closter, N J., for example, weve delivered polymer rollers that withstand 8-ton loads These rollers have been used in ski lifts and rigs that can raise an entire building But the primary task of most rollers and cam fol- 46 A biodegradable alternative to foam is grown NOVEMBER 8, 2012 ACHINE  How to AVOID ELECTRICAL HAZARDS with Pneumatic controls are a viable option when electrical hazards cant be tolerated air logic Authored by: Kenneth J Korane Managing Editor Key points: Air logic functions like relays, switches, and counters, but uses compressed air instead of electricity Air-logic controls are preferred in wet or dusty conditions because they pose little danger of electrical explosion or shock Resources: AOP Technologies, www.aoptec.com Clippard Instrument Laboratory, www.clippard.com from mushroom roots and agricultural waste D s 49 MLiterature Express NOVEMBER 8, 2012 FLUIDPOWER TECHNOLOGY GUIDE clutches and brakes How to rid foam of petroleum MACHINE DESIGN.com lowers is to transmit motion rather than support loads Regardless of their purpose, rollers and followers are commonly hybrid designs with polymer load-bearing surfaces over metal roller bearings or structural hubs These hybrid components, often sized as drop-in replacements for standard-sized all-metal components, offer compelling technical advantages due to their use of polymers: Self-lubricating Engineering polymers best suited for rollers are self-lubricating, a property that last the life of the component Bearing surfaces Authored by: made from these George Bartosh polymers never President require lubrica- Intech Power Core tion between the Closter, N J roller and rail Edited by Stephen J Mraz When combined stephen.mraz@penton.com with lubed-forResources: life bearings, polymer surfaces Intech Power Core, www.intechpower.com For another feature on eliminate mainplastic parts, scan this tenance costs code or go to: http:// associated with machinedesign.com/ regular lubricaarticle/plastic-gearstion, even those outlast-metal-0506 scheduled after washdowns 38 to design suppression 42 How circuits for electric Back-EMF in clutches and brakes may lead to erratic operation and a shortened life Cam followers and rollers from Intech put a gravitycast nylon 12 bearing surface on metal hubs and roller bearings Using nylon eliminates the need for lubrication and makes the components quieter than their all-metal counterparts Engineers might only glance at the dimensions and load capacities of roller and cam followers to ensure they will fit in their design before placing an order But they should pay closer attention because these components can make or break the performance of motion subsystems critical to a host of industrial machines Choose the wrong roller or cam follower and your design can be destined for a shortened life plagued with maintenance headaches, contamination issues, and speed limitations The wrong component can also drive up operating and manufacturing costs The right components, by contrast, will contribute to a longer life of reliable motion that engineers and buyers expect But how you pick the right roller or cam follower for the job at hand? The trick is considering not just sizes and loads but also the materials that make up the rollers bearing surface 38 More importantly, self-lubrication puts an end to the loss of performance and catastrophic failures common when metal rollers and rails arent regularly lubricated Wear resistance Metal-on-metal contact, even when both metal surfaces are lubricated, can result in excessive wear and galling Metal-on-metal wear affects rollers and rails, which are far more expensive to replace Plastic rollers eliminate this wear Clean running Self-lubricated polymers eliminate two potential sources of contamination stray lubricant and particulates from metal-onmetal contact For this reason, polymer cam folFrom cheap plastics to the worlds most-exlowers and rollers are a pensive composites, many types of polymers have good choice for medical, been machined, molded, or cast into rollers, cam semiconductor, foodfollowers, and other power-transmission compoprocessing, and cleannents Engineers at Intech focused their developroom applications ment eorts on a proprietary, gravity-cast nylon Smooth and quiet oper12 called Power-Core PA12GC It combines several ation Unlike metals, advantageous material properties polymers can dampen From a materials standpoint, Power-Core mainshocks and vibrations In tains its physical properties in a variety of operating cam followers, polymers conditions This stability lets engineers accurately absorb the damaging predict the materials behavior and life even when shocks and vibrations its exposed to varying moisture, temperature, and caused by reciprocating chemical levels motion This prolongs In particular, Power-Cores stability despite the life of machine bear- high-humidity and even total immersion, makes ings, especially in high- it well suited to power-transmission applications speed applications Most high-performance polymers absorb moisIn rollers, damp- ture, swell, and lose tensile strength Power-transing contributes to quiet mission components made from moisture-absorbmotion Polymer roll- ing (hygroscopic) polymers can end up too weak ers typically run about to carry the loads they were designed for and too 10 dB quieter than their swollen to work with mating components metal counterparts Power-Core also dampens vibrations, which They run smoothly too, lets it reduce noise and absorb shock loads that thanks to their precise power-transmission components commonly see roundness For example, To make these components, Intech gravity total runout on a macasts nylon 12 over metal hubs or thermally installs chined nylon 12 cam it over rollers bearings to create the beginnings follower with a 1.5-in of a cam follower, roller, or gear These blanks are OD would be less than then precision machine into nished components 0.001-in Gravity casting contributes to Power-Cores low Speed and efficiency internal stresses that gives the polymer a uniform Polymer rollers facilitate crystalline structure As a result, nished compohigh-speed, energy-effinents have a consistent machining resistance that cient motion in a three improves precision during manufacture and use ways First, polymer And under external load, the dense crystalline rollers weigh about 40% structure helps thwart stress-induced cracks and less than similarly sized swelling that sometimes lead to premature failure metal rollers, reducing  RS# 621 Magnum Venus Plastech, www.mvpind.com ESIGN Electrical and electronic devices such as logic circuits, programmable controllers, and PCs normally control fluid-power and fluid-handling circuits Such systems can also operate with air logic, controls that function like relays, switches, time delays, and counters However, while the circuitry is similar, compressed air is the control medium instead of electric current Air-logic controls are often preferred in wet or dusty environments because they pose practically no danger of explosion or electrical shock Likewise, air controls cannot ignite explosive or flammable gases and vapors And theyre rugged Water can splash on the controls without affecting operations, and they tolerate dust and dirt Air to avoid electrical 60 How hazards with air logic Pneumatic controls are a viable option when electrical hazards cant be tolerated 60 MACHINE DESIGN.com Air-logic controls for composites manufacturing rely on miniature valves, manifolds, and other components from Clippard Instrument Laboratory logic can also be used on machines with fluid-power components but no electrical supply Air logic does have disadvantages Most common is a lack of understanding among maintenance personnel on how to read schematics and troubleshoot problems Also, air logic with long control lines responds noticeably slower than electronics Thats because control lines longer than 10 to 15 ft fill and exhaust slowly compared to near-instantaneous electrical signals In addition, it takes NOVEMBER 8, 2012 60 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 NOVEMBER 8, 2012 %!#%##"%!"%  % %!%!#%##"% ""%$$$ Built-in simulator Program Do-more with the completely new - and FREE - Do-more Designer software (DirectSOFT and ladder programs More program memory More and flexible data type memory Faster program execution Easier-to-use instruction set Integrated Ethernet on the CPU Faster I/O for counting and motion applications More and easier-to-use communications developed with DirectSOFT are not compatible with these CPUs ) Download the FREE software! Get started fast! Choose a Do-more starter kit to get going fast You get: $$$% % % % The new Do-more H2 series CPUs leverage the existing line of DL205 I/O modules and base units to create an incredibly powerful PLC - at an incredible bargain Two CPU options are available: H2-DM1E $399 (1) USB port for programming, (1) full-duplex serial port, (1) Ethernet port H2-DM1 (1) USB port for programming, (1) full-duplex serial port $299 H2-DM1E Over 1M bytes total memory (includes program, data and documentation) H2-DM1 Program/monitor/debug over any embedded communication port Supports up to 256 I/O locally and thousands more with optional Ethernet remote I/O Supports inexpensive serial port expansion for connection to bar code readers, printers, etc Prewired, 3-slot base** with your choice of Do-more CPU 8-point input simulator module 8-point relay output module Do-more Designer software CD-ROM USB programming cable User manual Coupon for 30 days FREE online video training Starter Kit ** AutomationDirect reserves the right to substitute a larger base at its discretion H2-DM1E-START $626 H2-DM1-START $536 with H2-DM1E CPU with H2-DM1 CPU So visit www.do-moreplcs.com for the details, watch overview videos, and download the free software to take it for a spin Or go straight to: www.automationdirect.com/do-more-plcs to buy! www.automationdirect.com Go online or call to get complete information, request your free catalog, or place an order And each Do-more CPU comes with a coupon for a 30-day free trial of online video training 1-800-633-0405 RS# 103 DEPARTMENTS ON THE COVER Photo by R.L.Rubenking EDITORIAL More green cards, more H-1B visas 10 EDITORIAL STAFF 12 LETTERS 16 SCANNING FOR IDEAS Liquid cooling for servers also supplies hot water Gimbal mount expands drones view 20 REPORTERS NOTEBOOK 26 LOOKING BACK 33 SENSOR SENSE Metal-faced inductive sensors for durability 35 COMMENTARY Googles got nothing on Cat 36 INVENTORS CORNER Compact engine packs a powerful punch 68 PRODUCT SPOTLIGHT Linear actuators 72 PRODUCTS 74 BUSINESS INDEX 76 STATEMENT OF OWNERSHIP 77 AD INDEX 78 CLASSIFIEDS 78 BUSINESS STAFF For customized article reprints and permissions please contact: Penton Reprints, 1-888-858-8851, e-mail at reprints@pentonreprints.com 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 â 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 Intl $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 79 BACKTALK 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 MACHINE DESIGN.com NOVEMBER 8, 2012 POSTMASTER: Send change of address notice to Customer Service, MACHINE DESIGN, P.O Box 2100, Skokie, IL 60076-7800 EXAIR Blows Away The Competition! S e Over Save Ov r $1,200 P r Year Y r 200 Per R p i g One O Outdated O d d Air Nozzle! By Replacing Weve all seen at air nozzles Some are yellow Others are orange The oldest ones are blue or metal Those other manufacturers want you to believe youll save money by conserving compressed air while protecting your workers from harmful noise levels In reality, those colorful air nozzles that blow the air out of holes consume enormous amounts of air The plastic ones often break o Some might even get you an OSHA ne due to the dangerous dead ended pressures that exist if someone blocks the air exhaust EXAIRs award winning 2" Super Air Nozzle has been engineered to replace those outdated at nozzles There are no dangerous holes EXAIRs patented, award winning design is ecient, maintaining a precise amount of airow through a thin slot The result is a forceful stream of high velocity, laminar airow with minimal air consumption and noise You can increase or decrease the force of each at air nozzle using shims to tune it to the application so youll never waste compressed air Flat nozzles from other manufacturers can consume over 30 SCFM (a refrigerator sized compressor) and arent adjustable Some manufacturers oer dierent ow rates but you need to guess at which one will the job since you cant adjust them once youve made the purchase By default, most users feel bigger is better and go with the highest ow rate, wasting compressed air COMPARE Heres how: One popular flat nozzle consumes 31 SCFM @ 80 PSIG EXAIRs 2" Super Air Nozzle with 015" shim consumes 21.8 SCFM @ 80 PSIG 31 SCFM (theirs) 21.8 SCFM (EXAIRs) = 9.2 SCFM compressed air saved/min Most large plants know their cost per 1,000 standard cubic feet of compressed air If you dont know your actual cost per 1,000 SCF, 25 is a reasonable average to use SCFM saved x 60 minutes x cost/1,000 SCF = dollars saved per hour In this case, 9.2 SCFM x 60 x 25/1,000 SCF= 13.8 cents saved per hour 13.8 cents per hour x 24 hours = $3.31 saved per day $3.31 per day x 365 days = $1,208.88 saved in one year (in this 24/7 operation) And, This Savings Is For One Nozzle! Air Nozzle Yellow Air Consumption Noise Level lbs of Force @ 80 PSIG dBA @ 80 PSIG 29 SCFM 83 1.7 Orange 28 SCFM 82 1.7 Blue 26 SCFM 78 1.5 Metal (machined) 29 SCFM 82 1.7 Metal (cast) 31 SCFM EXAIR 2" Super Air Nozzle *7.3- 30 SCFM 80 1.9 62-81 0.5 1.9 *Air consumption dependent upon shim size EXAIRs 2" Super Air Nozzle can pay for itself in less than 15 days Put the 2" Super Air Nozzle to work in your blowoff, cooling or drying application Were sure youll agree that it blows away the competition! RS# 104 11510 Goldcoast Drive Cincinnati, OH 45249-1621 Phone (800) 903-9247 FAX (513) 671-3363 E-mail: techelp@exair.com www.exair.com/45/42san.htm @EXAIR The Guarantee Whats new online machinedesign.com FREE EBOOK Vibrations in designs incorporating gears: Sources, analysis, and solutions All moving machinery generates vibration which, in turn, wastes energy, degrades movement accuracy, and eventually leads to system failure This eBook, sponsored by Stober Drives, explains how careful vibration analysis reveals information that can be used to troubleshoot root machinery problems That helps keep electric motors, couplings, gearboxes, bearings, and other components up and running Download a free copy at http://machinedesign.com/ebook Power everything via USB The president of the USB Implementers Forum gives an overview of the new USB power-delivery standard, and how it could eliminate the custom power cords and bricks so many devices require It uses heavier cables, handles up to 20 V and 100 W, and can dynamically convert a device from a consumer to provider of power without changing the cable Learn more at www engineeringtv.com/video/PowerEverything-Via-USB-IDF-20;OnlyEngineering-TV-Videos EDITORS WEB PICKS Roller and conveyor chains A new 140-page catalog from iwis drive systems covers the design, selection, and application of a wide range of chains Content includes roller, conveyor, accumulation, flyer, and flat-top chains, maintenancefree and corrosion-resistant versions, modular belts for industrial applications, and products for timing drives Theres also a section on lubricants and lubrication methods Request or download a copy at www iwis.de/catalogues Power-supply site Mouser Electronics has launched a new Power Supply site It contains technical and design information, including the benefits of switchedmode power supplies such as high efficiency, small size, and light weight It also provides details on UPS and ac/dc applications Content includes product data, white papers, a library of technical resources, and info on products from major manufacturers Visit www.mouser com/power-supply-technology Dealing with digital The Agilent Technologies HighSpeed Digital site (www.agilent MACHINE DESIGN.com com/find/HSD) covers test and measurement products such as oscilloscopes, analyzers, and meters It delves into topics such as signal integrity, design and simulation, and high-speed digital analysis, and offers debugging tips The technical support area includes a library, FAQs, and discussion forums And a new white paper, Crossing the Digital-Analog Divide, explains how digital signals are idealized at high data rates, as well as how to cope with the physical nature of signals that engineers might prefer to think of as bits and bytes Bearings info Kilian Manufacturing, an Altra Industrial Motion company, has a new Web site on bearings and assemblies for demanding automotive and industrial applications It covers products such as ball, needle, roller, and thrust bearings, as well as customengineered specialty bearings and polymer assemblies Content included downloadable brochures, catalogs, industry specific application profiles, service manuals, and articles Visit www.KilianBearings com NOVEMBER 8, 2012 UPCOMING WEB EVENTS BASICS OF MOTION CONTROL WITH PLCs AND STEPPERS Online tutorial videos detail motion-control theory and application using PLCs as the supervisory controller A new 11-part Motion Control video series features the DirectLogic 05 PLC, SureStep stepping system components, and C-more micro HMI It starts with the basics of the hardware, describes typical motion applications, then moves through demonstrations using equipment such as a linear slide To view individual segments of this series, visit http://learn automationdirect.com and look under the Drives/Motors tab Four new Do-more PLC videos focus on using the new CPU with the latest high-speed counter module to perform motion applications using switches or encoders, as well as details on hardware setup and software functions such as trapezoidal moves To view this series, visit http:// learn.automationdirect.com and look under the PLCs tab for Domore PLC-Live demos Or find them all at: www.youtube com/automationdirect Become a subscriber and get alerts when new videos are uploaded :KHQWKHWHPSHUDWXUHLV) 4XDOLW\DQG3UHFLVLRQDUH&ULWLFDO )OH[LEOH&RXSOLQJVIRUPRWLRQFRQWUROV\VWHPV UHTXLULQJDFFXUDF\UHOLDELOLW\DQGYDOXH +HOLFDO3URGXFWV&RPSDQ\,QFDQGLWVHQJLQHHULQJWHDPKDYHRYHU \HDUVRIH[SHULHQFHGHVLJQLQJDQGPDQXIDFWXULQJLQQRYDWLYH SURGXFWVIRUFRQWUROOLQJPHFKDQLFDOPRYHPHQWLQFOXGLQJKHOLRVWDWV WUDFNLQJWKHVXQ 2IIHULQJDYDULHW\RIPDWHULDOVIRUFKDOOHQJLQJHQYLURQPHQWDO FRQGLWLRQVDQGWKHRSWLRQRILQWHJUDWLQJVHYHUDOSDUWV LQWRRQHSLHFH+HOLFDOảVH[LEOHFRXSOLQJVSURYLGH \RXWKHSHUIHFWGHVLJQVROXWLRQIRU DWLQJDQJXODUPLVDOLJQPHQW DFFRPPRGDWLQJDQJXODUPLVDOLJQPHQW HWDQGD[LDOPRWLRQ SDUDOOHORIIVHWDQGD[LDOPRWLRQ VXFFHVVIXO :LWKRYHUVXFFHVVIXO G GHVLJQVDQG VWRPHUV VDWLVHGFXVWRPHUV \QRWOHW VHUYHGZK\QRWOHW FRXSOLQJ +HOLFDOVWDUWFRXSOLQJ VZLWK \RXUGUHDPVZLWK \ UHDOLW\WRGD\ 32%R[:HVW0F&R\/DQH 6DQWD0DULD&DOLIRUQLD )D[ $6& ,62&HUWLHG RS# 144 FLUIDPOWER TECHNOLOGY GUIDE The widest range of gearboxes, gearheads, gearmotors and reducers available from a single source Gearmotors & Reducers Air logic minimizes fire and explosion hazards in composites molding operations Servo Gearheads so that would require explosionproof electrical systems, and they are quite expensive Instead, MVPs engineers opted for all-pneumatic controls using valves and logic components from Cincinnati-based Clippard Instrument Laboratory Spiral Bevel Gearboxes Air-logic controls Special Design Gearboxes and the experience to help you select the right one for your needs Let DieQua be an extension of your design team RS# 145 &RQWDFWXVWRGD\ ZZZGLHTXDFRP  The Innovator II control box is an air-logic panel with no electronics It is used primarily with MVPs Patriot mix/meter dispensing system, the companys newest generation of resin-dispense equipment specifically designed for closed molding This meter-mix system delivers precise quantities of resin and catalyst to the mixing head, blends them, and injects the mixture into the mold The pneumatic controls perform three major tasks, explains Tim DeLuca, vice president of MVPs RTM Div The first is to repetitively inject the same shot size into the cavity every time, eliminating guess work on the part of the operator Once userdesignated injection parameters are reached, a counter circuit shuts off injection Second, the controls manage injection pressure and prevent overpressure conditions which could blow out clamps or resin seals, says DeLuca A pneumatic switch called a PV switch can be mounted in the mold to sense resin pressure for closed-loop control NOVEMBER 8, 2012 Customers who require higher precision, say for aircraft or automobile parts held to tight tolerances, are more likely to want this option, notes Austad Overpressure can result in parts with inconsistent thickness So sensing pressure lets the controller slow the pump, shut off the injector, or both The last, and perhaps most important, function is the control interlock At no time can operators accidently push the wrong button and botch the process During certain cycles, some functions are locked out and not usable This prevents costly mistakes, says DeLuca Precise pumping Precise metering was a key objective when the Patriot was developed It ensures a catalyst-to-resin variance ratio of 1% or less A pneumatic motor drives the resin pump which, in turn, is connected by a slave arm to the catalyst pump In this way, the catalyst pump is directly slaved to the resin pump, ensuring accurate metering as both catalyst and resin are delivered to the mix head The air motor driving the pumps uses line-pressure pilot valves, which shift a four-way valve spool to reverse the pump Keys for quickly reversing the pump are a light spring load on the pilots and large exhaust ports on the valve Also, the air cylinder has a 2-in stroke that minimizes Technology You Can Trust Avago Encoders From Miniature Modules to Complete Housed Encoders Avago has the industrys broadest range of absolute and incremental encoders for motion control Choose from encoder modules or complete housed encoders in a wide range of resolution, shaft sizes, mounting options, and output formats AEDR-8500 Worlds Smallest 3-Channel Reflective Encoder t Miniature size ideal for motors 6mm to 35mm in diameter t Flexible resolution by changing code wheel size t Built-in interpolation at 1X, 2X, and 4X to achieve higher resolution Avago Housed Encoders t Comprehensive selection of housed encoders for any application t Wide range of resolution, shaft sizes, and mounting options t or channel versions with single-ended or differential output signals t Drop-in replacements for housed encoders from US Digital and other manufacturers For further information, visit us at: www.avagotech.com/encoders RS# 146 FLUIDPOWER TECHNOLOGY GUIDE the volume of air that must exhaust when the pump reverses Older versions used and 6-in stroke cylinders, which take longer to exhaust due to the greater volume of compressed air All this adds up to faster pumping with quick changes in direction Low-friction seals, along with a balanced power ratio pneumatic drive, help ensure uniform material delivery at high and low flow rates, says DeLuca COATED INDUSTRIAL DEVICE The Leader in Coating Industrial, Medical, and Aerospace Components 51 Parmenter Road, Hudson, MA 01749 (800) 258-0110 www.boydcoatings.com/MachD Innovative design The Innovator II is based on controls originally built in the United Kingdom for a specific model of MVPs meter/mix equipment That unit used European-standard components and metric tubing We wanted an Americanized version for North America with Clippard valves, standard tubing, and other components that are readily available, says Austad And MVP wanted the controls to work with a variety of its equipment Looking to build greater versatility and functionality into the controls, engineers from MVP and Clippard distributor AOP Technologies, Auburn, Wash., made key improvements, notes DeLuca We changed all the control lines to 1/8-in OD to get faster reaction times on the circuits All of the valves that actually control outside sources were upsized to allow for more flow so that we could use longer trigger lines outside the box, he says Using stand-alone brass valves from Clippard, we arranged valves into banks. Four of the valve banks are essentially complete circuits, to ease troubleshooting The fifth is an overall control circuit with flow controls for system tuning Some redundancies were removed and common valves were used when possible to reduce the number of different parts, notes DeLuca Another important feature: the RS# 147 NOVEMBER 8, 2012 MVPs Innovator II controls are shipped worldwide and built for durability and low maintenance solvent flush cannot back up into the air supply and ruin the entire controller, thanks to a sacrificial blocking valve added to the circuit In addition to converting to inch-size fittings and tubing, the plumbing was streamlined and secured with clips for a better appearance and easier troubleshooting Also, all 70+ lines and valves are labeled for identification versus the schematic Finally, the control box can handle remote-control pendant operation, multiple feedback devices, and different styles of mix-meter equipment Ensuring reliability Although the box is designed primarily for the North American market, MVPs machines are shipped worldwide This makes reliability, along with minimal maintenance, essential, according to Austad From MVPs standpoint, we have used Clippard products in our pumping systems for many years, with good results, he says The design relies on standard components and Clippard has worldwide distribution So in case there is a problem, users can go to their local distributor and get it repaired and up and running as soon as possible. Because of the proven reliability and durability of Clippard air-logic valves, we expect these systems to be trouble-free for many years, adds DeLuca Other than cleaning the air filter, no maintenance is required. MD RS# 148 RS# 136 RS# 149 RS# 150 SPOTLIGHT LINEAR High-force linear actuator The High Force Linear Actuator Model LA100-93-000A packs a 500-lb peak force a level that typically requires two actuators and a continuous force of 292lb with 2-in total stroke The device features a semihoused construction with built-in shaft and bushings that orient the coil assembly concentric to the field assembly, which makes actuator mounting fast and easy The unit measures 10in in diameter and 9.3in long at mid stroke BEI Kimco Magnetics, 1499 Poinsettia Ave., Suite 160, Vista, CA 92081, (800) 572-7560, www beikimco.com RS# 446 ACTUATORS Linear actuator for food-grade applications The stainless-steel Hygienic Green Drive linear actuator is suitable for food-grade applications as well as clean-room environments The actuator comes with a 16 or 25-mm-diameter shaft Available with a variety of coil windings, it features rated forces between 8.4 and 96.1N, acceleration forces (peak force) from 33.7 and 384.5N, and rated currents between 0.53 and 1.85A The Drive offers built-in feedback electronics, including position sensors, interpolation electronics, and temperature sensors Nippon Pulse America Inc., Corporate Dr., Radford, VA 24141, (540) 633-1677, www.nipponpulse.com RS# 447 r formation via ou Request free in Web site at ice rv Se Reader c design.com/rs ww w.machine Linear units First in the companys new family of Actuatorline products, the ELM Series linear units feature highspeed and low-noise operation The units come in several sizes offering a range of stroke lengths, load capacities, and shuttling speeds ELM units are made of anodized aluminum extrusions for high mechanical strength and low weight, and have a steel-reinforced polyurethane timing belt with either an AT pitch or parabolic profile The units have polyurethane sealing strips to protect internal parts against dust and foreign matter, with an optional bellows for critical environments The units feature a maintenance-free ball bearing guide within the extruded body and offer speeds to 5m/sec, high-load capacity and bending moments, low friction, and a 20,000-km service life without relubrication Measuring 50 ì 50 mm to 110 ì 110 mm, the units maximum axial loads range from 530 to 2,650 N, with stroke lengths from 100 to 3,700 mm, depending on the model All units support loads in any direction and may be installed in any position Units may be fitted with a variety of drive systems based on application needs, with the driving pulley attached to the reduction gear shaft by a tapered coupling for high accuracy and long life For highly 68 MACHINE DESIGN.com NOVEMBER 8, 2012 dynamic robotic, automation, and material-handling applications involving stress cycles and high-precision requirements, a model with planetary gearing is available Standard models feature to 15-ft clearance and reduction ratios of 1:3 to 1:1,000 Versions with worm gears are suitable for applications involving low speeds and accelerations Rollon Corp., 101 Bibly Rd., Suite B, Hackettstown, NJ 07840, (973) 300-5492, www.rollon.com/USA/ RS# 448 IF YOURE STILL USING A ROTARY PHONE EZ INDEXER :[H[LVM[OLHY[ZLY]V KYP]LU[LJOUVSVN` 4PJYVZVM[,_JLSIHZLK ZWYLHKZOLL[ZMVYZPTWSLZL[\W *VTWSL[LZ`Z[LT -VYSVHKZMYVTV\UJLZ[V [LUZVM[OV\ZHUKZVMWV\UKZ 7YPJLKYPNO[ Nickel Conductive Adhesive Cures Rapidly at Room Temperature EP76MF Epoxy System ỡ Low volume resistivity ỡ High bond strength ỡ Chemically resistant ,HZ`[V0U[LNYH[L9VI\Z[*VUZ[Y\J[PVU 5V4HPU[LUHUJL 154 Hobart Street, Hackensack, NJ 07601 USA +1.201.343.8983ỡmain@masterbond.com www.masterbond.com ^^^JLU[YPJP[`UL[ZHSLZ'JLU[YPJP[`UL[ RS# 152 RS# 151 Ultra Small Formed Metal Parts Photoetching combined with precision metal bending to create extremely small features in thin metal i>èếiấ`ĩấèấọọẻá ấ ếvii]ấèiviiấô>èấấèV>èiấ Vôiíấ>ôi ấ 7`iấ>ièịấvấiè> ấ "ièôấôấvấièVi`]ấvi`]ấi>èấ èi>èi`]ấ>`ấô>èi`ấèấiè>ấô>è ấ *èèịôiấ`iii`ấấxấ`>ịấ Capabilities Brochure and Full Specs at www.tech-etch.com/photoetch ,62 9,.0:;,9,+ TECH-ETCH, INC., {xấ`ấ,>`]ấ*ịếè]ấấọểẻẩọấUấ/ ấxọnầ{ầọẻọọấUấ8ấxọnầ{ẩẩẻ RS# 153 SPOTLIGHT LINEAR ACTUATORS Linear-motion platform The SIMO (Simultaneous Integral Milling Operation) Series linear-motion platform lets design engineers meet multiple application requirements within a single platform Its consistent geometry creates a platform of interchangeable options, including Rail heights low profile for tight spaces or a tall version for structural integrity Each aluminum base rail features the SIMO process for substantially less bow and twist, and better flatness Three bearing tribologies; selflubricating FrelonGold plain bearings, which are suitable for contaminated environments; V-wheel roller bearings for high speed applications; and profile rail linear guideways with recirculating ball bearings for rigidity and precision Three drive types leadscrew with machined nut or antibacklash nut, ball screw, or two versions of belt drives The mix-n-match feature lets engineers test multiple configurations and easily adapt to changing requirements dependent upon load, speed, accuracy, environment, and life considerations PCB Linear, 6402 Rockton Rd., Roscoe, IL 61073, (888) 389-6266, www.pbclinear.com/SIMO-SeriesLinear-Motion-Platform RS# 449 70 MACHINE DESIGN.com RS# 154 NOVEMBER 8, 2012 &RQWURO6ROXWLRQV7KDW$FWXDOO\*LYH[...]... I know that getting parts from machine shops is not easy or inexpensive With the small budget most inventors have, this kind of resource could be a real boon to me and people like me Mark Stapelton 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,... a source of hot waste for a secondary purpose such as heating nearby buildings RS# 401 16 MACHINE DESIGN.com NOVEMBER 8, 2012 Servers vertically installed in coolant bath Evaporative cooling tower releases heat to the atmosphere r formation via ou Request free in Web site at Reader Service c design.com/rs ww w .machine Our plotters are the fastest in their class THE NEW EPSON SURECOLOR T-SERIES ® ® •... that measure and control temperature, humidity, pressure, strain, force, flow, level, pH, and conductivity NEW SERVICE Get a QR code reader at http://getscanlife.com 2012 GGB All rights reserved 28 MACHINE DESIGN.com RS# 123 NOVEMBER 8, 2012 Agilent Technologies, Santa Clara, Calif., has been designated as the first nongovernment calibration agency under Japan Radio Law by the Minister of Internal Affairs... Korane MECHANICAL Lindsey Frick Kenneth J Korane EDITORIAL PRODUCTION Denise Greco Editorial Production Manager Randall L Rubenking Art Director 1300 E 9th St Cleveland, OH 44114-1503 10 MACHINE DESIGN.com RS# 110 NOVEMBER 8, 2012 ƵƚŽŵĂƟŽŶĞƋƵŝƉŵĞŶƚƌĞƋƵŝƌĞƐŝŶŶŽǀĂƟǀĞƐŽůƵƟŽŶƐĨŽƌŵŽǀŝŶŐƉŽǁĞƌĂŶĚĚĂƚĂ ĂĐƌŽƐƐƌŽƚĂƟŶŐŝŶƚĞƌĨĂĐĞƐ͘DŽŽŐŽīĞƌƐŽǀĞƌϭϬ͕ϬϬϬƐůŝƉƌŝŶŐĚĞƐŝŐŶƐ͘DŽĚĞůƐ ĂƌĞĂǀĂŝůĂďůĞŝŶĐĂƉƐƵůĞ͕ƚŚƌŽƵŐŚͲďŽƌĞĂŶĚĮďĞƌŽƉƟĐĐŽŶĮŐƵƌĂƟŽŶƐ͘... *HDUVKDSLQJWRμLQGLDPHWHUμIDFHZLGWK 'HVLJQDQG$QDO\VLV H[FHOOHQWVRIWZDUHFRP  5HYHUVHHQJLQHHULQJVHUYLFH :LQGWXUELQHJHDUER[KLJKVSHHGVSLQGOHVJLPEDOKHDGV DQGJHDUER[HV 18 MACHINE DESIGN.com NOVEMBER 8, 2012 RS# 116 RS# 117 REPORTER’S NOTEBOOK How to … HOT ROD an electric motor Dennis Berube’s Current Eliminator V electric dragster Berube doesn’t discuss construction details of this, his... Resources: Brushes Dennis Berube’s Current Eliminator site: http://www.currenteliminator.net/index.htm Armature Lawless Industries Ltd., www.paradefloats com/orange.html MACHINE DESIGN covered Shawn Lawless’ electric drag bike earlier this year: machinedesign.com/ article/electric-motorcycle-tops-200-mph-0809 Armature windings EngineeringTV also did videos of the Lawless bike: www.engineeringtv.com/video/All-ElectricDrag-Racing-Motorc... explains Lawless Finally, drag racers know when to shut things down “You can’t run the motor long because it only has so many windings,” says Berube “You are eventually going to overheat.” MD NOVEMBER 8, 2012 MACHINE DESIGN.com 21 REPORTER’S NOTEBOOK How to convert technical manuals Authored by: James I Finkel Engineering Manager It sometimes becomes necessary to convert a technical Wallace Cranes manual... which can damage MOS devices RFID vs Barcode: Which track and trace technology is better for your application? 2012 TURCK askTURCK.com RS# 120 We Mold Ideas Into Reality High tolerance components and assemblies are what we work with everyday at Minnesota Rubber and Plastics Our experience in design, sealing and manufacturing complex devices has made us the preferred partner for industry leaders throughout... 6HUYR%HDPŒ&RXSOLQJ =HUR%DFNODVK Made in USA A Misalignment 7º angular 025” radial 050” axial Phone 1-888-260-7466 Fax 516-771-6444 sales@ondrivesUS.com www.ondrivesUS.com/ServoBeam 26 MACHINE DESIGN.com NOVEMBER 8, 2012 polymer flex member US Corp 30 YEARS AGO — 1982 Handyman’s tool pinpoints air leak: A $20 energy-audit tool called Thermo Guard by Metrifast, New Hyde Park, N Y., locates drafts around... order that it fits your application to a T Make your own switch using the widest range of electrical connections in the industry .com NOVEMBER 8, 2012 Check out our TT switches online and see how easy making the switch can be http://nasonptc.com/ttswitch RS# 113 MACHINE DESIGN.com Don’t forget to request your own sample: http://nasonptc.com/switch_form 800.229.4955 • www.nasonptc.com Watch “Making the

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