Teaching Power Tools to Run Themselves
Transkript
Teaching Power Tools to Run Themselves
Editot Vor.re Tonnnx trf cchanicsand H andicralt NEG. U.S. PAT. OfF. Foundeilin 1872, Vol. 167: No, 2 llfanaging Ed,itot Howenp Ar-r-ewey Art Editor Howeno C. JrwsrN ,-.4-eraaz {r,rat"gr Wer*/da,%y'gaz;nc,fu 83 7^ AUGUST. T955 Will Detroit Build V.6 Cars?.. .... 65 Kansas Mine Becomes7-Aere Food Freezer.. 70 A..ociaac Edtaors -{lden P. Amagnac, Stmley Beitler, Henry B. Comstock, Devon Frmcis, Sheldon M. Gallager, Herbert O. Johansen, Martin Mann, Everett H. Ortner, Ruth Wesdrhal. Ara llarry Samuels ( Director), Herberl Anthony, Gene Butera, Eric A. Kamiroki Ir., Henry W. Kazmirowski, Dana B. Rasnussen, Layleu H. Sweet. copv Kendall W. Goodwyn (Director), Frmk Dorr, Georgette Spaks, Haniet Trowbridge. ?ll.T:i i::::::.1':'.:i L;..;....::::.'.: 1O Years of Atomic Progress Atomic lllilestones Since Hiro shima. ......... T ornorrow : Atomic Traoel........ Atomic Power Plant to Seroe New York.... Nations Race to Harness Atotnic Pouer.... 7B BI B2 B6 W h a t ' s C o m i n g i n 1 9 5 6 C a r s . . . . . . . . . . . . . . . . . . . . .B. .B. Detroit Prepares to Stress Safety................ 89 N o w Y o u C a n D r i v e B e t t e r a t N i g h t . . . . . . . . . . . . . .9 3 Flying Firemen SaveForests........................fOO Teaching Power Tools to Run Themselves..l06 Gas-Engine Wizard Turns to Steam Power..l14 Super Suburb fs a Country City....................12O H o w S t r o n g A r e O u r M i s s i l e s ? . . . . . . . . . . ...... . . . . 1 2 4 New Truck Shapes Tested in Wind Tunnel..l30 He Built a Play Town......... .......132 Gus Slices Out of the Rough. .....f38 o a a a a a a a o a For the Home Mechanic What You Can Do uith Flex Vheels........l4l Hout to Seroice Your Oil &urner..............146 The Case ol the TV Rasters ....151 a a a a . S i x U s e s f o r a C o m p a s s . . . . . . . : . . . . . . . . . . . . . . . . .1 . .5. .4. . . His Shop Was for the Birds... ...157 Home.Built Wheelbarrow Likes Tough Jobs 166 How to Apply a Rubber Roof......................f80 Vacuum-Cleaner Motor Opens Fan Window lB2 Pull-Out Bed Converts Car to Camp............18s 'Brrildirrg f o r t h e B i g B l o w s . . . . . . . . . . . . : . . ... . . . . . . 1 8 6 I Fly a Control-Line Trainer.. ....189 Outriggers,Steady My Outboard Canoe........194 H o w a M e t a l D e t e c t o r W o r k s . . . . . . . . . . . . . . . . . . . . . .l .9. B (More leaturet t rorurnnscreNcr and, d.epantments are licteil on WEe 4) Photography W. W. Monis (Director), Luckett, Orlando Guena. Hubert A.tistona DIanaging Ed,itott Frank Rowsome fr. Robert P. Steveroon llechanics Harry and Eand,ictolt Walton Midoettern Editot Kenneth Wylie (Cbicago) Pqcific Coasa Ediaor Wesley S. Griswold (Los Angeles) Editofiol Acsbnnat Rosa Lee Beelmd (Chief ), Louise Levis, Roberta Muks, Helen Stratton, foan Wolf. Publixhet Gorrnrv llevrr'roro Ptesidenc Rer-prr H. Fr-yNr.r Ad.tertising Manager Lrr P. Anevs Circulation Direcaot Eucsxn Warsox OFFICES: ADVERTISING xnw rox-358 Fourth Ave, csrclco-360 North Michigan Ave. prrnorr-820 Book Bldg. sAN FruNcrsco-l14 Smsome St. Citizens Bldg. crnvnrlNn-328 ros eNcBrrs-I127 Wilshire Blvd. PoRTLAND, oru.-520 S.W. Sixth Ave. EDITORIAL OFFICES: 858 Foiuth Avenue, New York 10, N. Y. Publtshed moDthly at 353 Fourth Avenue. New York ,10, N. Y., by Popular Scteoce PubltshiDg Co., Inc., Godfrey Ilammond, Chailman of the Board: RalDh g. Flynn, President aDd Treasurei: Ftanklin E. Parker Jr., Secretary; EuFeDe Watson, Vice-President. Srcondctais mail privileges authorized at New York. N. Y. and Dayton, Ohio. Entered as secoDd-cl&ssmatter at the Post Ofrce DeDartment, CaDada. Printed tx U.S.A. Coayrisht; 1955,by Popular Sclence Publishinc Co., Inc. All rishts reserved iD rhe United State6, Great Britain, and ln all the countries participating in the Intern&tional Copyright, Conventlon and Convention. Pau-American Copyrtghtgnited States, Yearly subscrlptioDs to irs possessionsand Canada, $3 40 (2 years, $6.00;3 years, $8.00); foreign per year extra. Four weeks' coutries $1 lotice is needed to chanSe a subscriber's address. Please give both old &nd new addresss, lncludlng postal rcne Dumbers. t ln an electronic lab at MtrTz engineers nou) are Teaching PowerTool toRun Themselve By Hartley E. Howe Punches in tape code size and time ol each cut. (-\O JOE WORKSHOPPERffgureshe'd tit to turn orrt a set of diiing-room \ " \--' chairs-arrd at the sametime break in his nerv \4odel 100 SuperTapemaster. Joe rvhips down to the hardware store and looks over photographsof different designs.He settleson a Swedishpattern 'rvay popular back in l9S5-delicate and handsome,but full of difficult reverse cllrves. That doesn't worry Joe. He plunks dou'n $I0 for a rveekt rental of o but"h Tape is led into computer where code is conaerted to elecaric signals. Too big yet for home shop, this MIT milling machine is run by computer-controlat left. of tapes-one each for legs, arms, back and seat. That night, he clamps a nice piece of birch into his Tapemaster, slips the tape into the control box, flips the switch, and sits back with his pipe.and the new issue of Outcloor Life. Forty minutes later, the rumble of the Tapemaster stops and Joe takes a look. One leg is finished. So he clamps on another piece of birch . . . Sure it's a dream-in 1955. But the Signals cotttrol thrce-dimensioral engineering basis for Joe's Tapemaster exists right now. Sitting up in the Servomechanisms Laboratory of the Massachusetts Instihrte of Technology in Cambridge, Nlass., is a milling machine that will turn out any metal part at the command of a little roll of tape. Originally 28" Cincirmati a standard, vertical Hydro-Tel, it now has hitched to it $50.000 worth of electronics. To conceive, design and build the MIT machine took some quarter-million moaement of cutLer head' time each cut, Trfl PAPER TAPE is punched on standard equipment used in teletypewriters. Operator follows code cHrections, in whieh blueprint lines have been changed to column of ffgures. pushes needlelike ffngers against TAPE R.EADER paper strip. Wherever there is a hole, steel ffnger goes through and completes an electrical circuit, sending a code signal. clollars. 250 electron tubes, 280 pilot machine tool-to make the nart on the Iights, 175 relays-and brilliant engineer- blueprint. ing on the part of Tech's Department of Turning a blueprint into holes in a Electrical Engineering. As father of a tape-"programming," they call it-rervhole new family of machine tools, it quires a ulan who knows machining, rvill earn its keep many times over. tools and metals. He has to break up What we cc.n ex.pect Whether such every curve in the design into straight industrial giants can be scaled down to lines. The automatic machine cuts home-shop size and price is anybody's 'straight lines only-but they can be as guess. But it is no guess that these tape- short as .0005 inch. A series of such lines eaters are going to bring a lot of eye- is a curve for all practical purposes. opening changes to industry. Someday, The programmer next translates each ,perhaps... straight line into numbers. Three numo A remote overseas base will be able bers represent distance of cut in each to make a desperately needed part in direction: up or down, back or forth, a few hours by plugging a machine sideways. A fourth number tells the time tool into a radio receiver. the cut will take. o \4achines in factories spotted across Typing out a pattern. The programthe country will all be controlled from mer then codes the numbers into a patone central headquarters. tern of holes in the slim paper tape by o Little machine shops will be able to operating a typewriter-like machine. do big jobs by buying or renting con- This machine, and the tape it makes, trol tapes. are much like'the ones used for higho Automobiles may change design more speed Teletypes. often-perhaps even seasonally-thanks The programmer's final job is to feed to tapes that cut tooling-up costs. the tape into the machine director, esThree things make all this possible: sentially an electronic computer. From First, blueprints can be converted into now on the machine is on its own. numbers ( hence the name "Numerical When the tape is run through the diControl").. Second, the numbers can be rector, tiny steel needles ffnger the holes converted in-to a perforated paper tape and read the numbers, changing them rvhich generates electric signals. Third, into electrical signals. These signals can the signals can operate controls of a be recorded, transmitted by radio or wire, llf$ rorurrnscrrNcr DIE BtoCK for master piston rod of a radial airin solid craft engine was cut automatically steel, using tape controls, Run was continuous except for halt to change cutter. PAIR OF DIES is checked against a dummy piston rod molded in dies made in earlier run. Exact fit showed complete duplication resulting from re-use of the same control tape, and reproduced anywhere in the world. From these signals, the computer figures the rate of feed and orders servomechanisms to adjust the speed controls of the machine's three hydraulic feeds. The actual movement of the cutter throush the metal mav be momentarily slowei or faster than expected becaus'e of variations in rnetal hardness and dulling of the cutting edge. To catch such errors. the computer constantly inspects both the orders received by the servos and the actual movement of the cutting tool. If either difiers from that on the tape, the computer automaticallv sends corrections. These "feedback" inspections do a good job. The control system is accurate to .0005 inch, much more precise than the .002-to-.004-inchtolerance of the machine itself. Despite its cornplexity, the nlrmerically controlled machine is dependable. If anything goes wrorlg in the controls or machine, alarm circuits stop everything before the work can be damaged. In thousands of hours of operation, the elec- NO HUIIAN OPERATOR had to watch work, so blocks were covered with rvetting agent during die cutting. This speeded work, reduced cutter wear. Note next block ready on table. lContinueil on page 222f '4^ , tu' i ruousrressl|l$ r eachi nerrool GetGoodPerformon(e theWuyBigtleetsDo. . . Eosl Texos Molor Freight, Dollos, Uses Federol-Mogul Engine Beorings Some 500 communities between the GuIf of Mexico and the Great Lakes know East Texas Motor Freight's direct daily service. ETMF keeps its modern equiPment in top shape bY careful maintenance work. For many Years' ETMF has been a good user of Federal-Mogul engine bearings. oil-control bearings Federal-Mogul have led in the replacement field for 30 years-because of quali'ty ! Get this quality, next time your car engine is overhauled. It costs no more to get the best-ask Your mechanic ! for New P o w e r. . . |VlOGUL FIDERAL OiI-Control Bearings RESEARCH . DESIGN . METATI'URGY ' P R E C I S I O NM A N U F A C T U R I N G S E R V I C E lll rorutrn sctENCE efves ?o,f,"I"rir! ?frfs tronic director has been down only three Dercent of the time. Much of this was ^tlue to a design defect now corrected' Remote control, repetition of operations, saving in skilled manpower-therse advantages of the MIT control system are important. But what makes the industry really happy is that it can do a run-oi-the-shop job faster and better' Up to now] automatic machine tools havJ bee.t either very expensive special machines that make- one Part and no other or general-purpose machines that *odel or template' must follo"w ^ "ottly still handle some must operator A skilled controls ani determine running speed' Illakes ar',lt part. The tape-controlled machine can be used for anY Part, not just one. There is no expe-nsive process bf modelmaking. And the final run is at high speed, completely automatic and completelv accurate. Vtaking a particular airplane palt by conventidnal methods requires 27 hours for set-up and a 169-minute milling operation. Making the same .part with tape controls requires 16 hours for tape preparation, tw6 hours for set-up, and a 39minute run. For any re-run the tape nreDaration would be eliminated, and ihe^savins would be 27 hours and l0 minutes! Standardized components and circuits can be expected to trim the cost of the NIIT system sharply on production models. Even so, the computer for the director is unlikely ever to become exactly cheap. Fortunately, however, one director can control as many machines as desired-and at any distance. Thus a director is not needed for each tool. But what really takes Numerical Control out of the millionaire brackets is the fact that the electronic signals produced bv the director can be recorded mag,rLticallv. Anv machine fftted with the less costly seivocontrols-far ,r"""rroiy than a director-can use this magnetic recording to direct its movements. Thus a machinl owner who can obtain recordlContinueil on page 224) Teachin( Tools to Run TfiemsefYes STOP SAEEINE REARS! Al R U Fr ;:::#'j' fREtl. . . tip-pqckcd titeroturc on Air lift romedies lor rog. ging reo6. Wrife Dept. | 38. FURlIACE FACTS! Hcoring Quolity IIRM IOUllDAIl0ll lor TRAI1ERS HOME-MADE 1)4" shown, feature Model I-UCO, solid st€el axle, loads 25OO lbs. Comes 'completely equipped, except for tires. 965.29 postpaid (when paid in advance). Many other models. We manufacture a complete Iine of trailer axles, couplere and jacks . . . tell us what you need! HAmtnER B10Wr00t c0. WAUSAU t4-H W|SCONSIN ings doesnt even have to own a director. And soon it will be possible to convert ordinary non-automatic machines to tape controls at minimum cost. Work tables will be made with all three feed mechanisms, and all servocontrolled. The cutting head itself can be ffxed in place. Thus the uses of automatic controls are not likely to be limited to the big bovs of indushv. Medium-sized concerns that dont want to make a big investment in a director-computer will be able to send a blueprint to a computer service center. Back will come a custom-made recording of the product that can be plugged right into a machine. Such computer service centers already exist. industries like Big mass-proiluction plenty of uses for will ffnd making auto Numerical Control. It can mean more frequent changes in models-and more specialized types such as sports cars and sportsman's wagons. Today the body dies for each model require an expensive process that starts with clay models, proceeds through a series of carved wooden replicas, and is climaxed by a steel die practically worth its weight in gold. With Numerical Control, there will be a far smaller investment to be paid off. Plane makers have long been eager to utilize automatic machines, but the production run of a typical aircraft part is too short to pay off the big cash investment needed for the specially built, onepurpose type. Tape controls provide automatic machines that can do many difierent iobs. A whole family of such machines is being developed by aircraft builders and machine-tool companies. Some experts predict that rocket-plane parts of the near future will be beyond the ability of human machine operators to turn out. It will be automatic tools END or nothing. 5Pn'r'G Car got that "middle age spread" look? Even new cars need help for overloads ol luggage, equipment or extra passengers. AIR LIFTS fit between leaf springs and frame inflate with air to support overloads up to 1000 lbs! Perfect for vacation trips, and so easy to install. See your dealer or write for his name. How You Con llccturo fContinueil lrom page 2221 Auto-Suggestion The sign which contributes most to safe driving is the one on the side of the car that reads "Police."-Iluds on N eu sletter. 224 popurrnsoENcE