Illustrated Sourcebook of Mechanical Components Part 14 docx

Creative Assemblies 27- 11 , Diuphragms . Piston Double-acting actuator provides for thrust in either direction by placing two diaphragm assemblies back to back. Diap n raynm Regulating valve controls the value ot air pressure by means of a diaphragm-bal- 4 anced valve and two control diaphragms. Diaphragm ' u+- I Shaft Shaft seal uses lubricant pressure to force the sidewall of the diaphragm to 8 roll against the shaft and housing. Double-acting pump has two diaphragms to give smooth and continuous flow of fluid 5 to equipment at a safe working pressure. Damping mechanism prevents abrupt or sudden motion in a machine. Damping 9 amount is controlled by orifice size. 27- 12 Control-Locked Thwart Vibration and Shock Critical adjustments stay put-safe against accidental turning or deliberate fiddling with them. Frank William Wood JR. w Clamp knob a SPLIT YOKE clamps on shaft when eccentric squeezes ends of yoke together. Knurled knob is handy for constant use, and eliminates need for tool. Another advantage is high torque capacity. But this design needs considerable space on panel. 2 FINGER springs into place between gear te h at turn of cam. Although gear lock is ideally suited for right-angle drives, size of teeth limits positioning accuracy. Knurled Split I 3,. SPLIT BUSHING tightens on control shaft, because knurled knob has tapered thread. Bushing also mounts control to panel, so requires just one hole. Lever, like knob, does away with tools, but locks tighter and faster. For controls adjusted infre- quently, hex nut turns a fault into an ad- vantage. Although it takes a wrench to turn the nut, added difficulty guards against knob- twisters. ' Control shaft Hex nut-' 4 CONSTANT DRAG of tapered collar on shaft makes control stiff, so it doesn’t need locking and unlocking. Compressed lip both seals out dust and keeps molded locking nut from rotating. Creative Assemblies 27-13 5. . TONGUE slides in groove, clamps down on edge of dial. If clamp is not tight, it can scratch the face. 6,. SPOT-BRAKE clamp is self-locking, which means it takes two hands to make an adjustment, one to hold the clamp open and one to turn the dial. 27- 14 Li uid level Mechanisms - In 3 icators and Controllers Means of determining liquid level, detection of changes in liquid level, transmission of indicated levels. or warnings of changes heyond set limits; and means of using level changes for level control, or control of other con- ditions such a5 temperature and pres- sure, have been accomplished by numer- ous mechanisms. The most pcpular & -Ffoaf chamber devices employ floats or pressure meas- urement with instruments such as the U-tube manameter, bourdon tube, and bellows. The methods shown here are largely indicating methods or simple devices for automatic control of liquid level al- though they can conceivably be applied to control other conditions such as tem- perature and pressure. Methods using electric resistance of a column of liquid and measurement of pressure changes by means of piezo-electric crystals are not shown. Patent No. 2,162,180 de- scribes a method involving determina- tion of change in air pressure when a measured volume nf air is introduced into a tank. Fig. 1 -Float and Lever- Operated Pilot Valve Sfof for fioat counterweigh f ann Sfop for f/oaf , 1 movemen f ' fed or dece/erated movements ofplunger for any floaf movemen U Fig.2-Float and Cam- Operated Pilot Valve Bourdon tube sqpporfs magnefic core in re- sista7ce coils ~ i Y (Magnefic core flfi v v _ : i tmavbe~ud- /ndicafor or recorder - I F/ouf , IM II <i r pokted C;i;-'o by float in mercury I/ - tube) 4ire connecfion fo gafvano- meter in receiver Fig.4-Float and Pulley Indicator Fig.5-Pressure Dome Indicator- Creative Assemblies 27- 1 5 Sec+/ona/ view excepf for weigbfs and ffoaf Fig. 6-Float Control of Discharge Tape visible Vapor- figh f covers / through window Tank floor, At-Pu//ey frome supporf Fig. 8-Tank Roof Indicator . I _-__ - Fig.7-U-Tube Manometer with Water Columns Double bdancing mechanism fUfs mercury swifcbes for u/arms when refri eranf is be/ow eifher operufing or idle &e/s - -Groo ves : F/oafing frigerun f sdmpling reservoir Fig.10 -Refrigerant Balance Back Front Fig.9-Dip Stick I ndica tor liquid >eve/ 5.50 indicufed b y /tgh f reflecffon from menrsrus Fig.11 -Automatic Battery Filler 27- 16 Liquid Level Indicators and Controllers Thirteen different systems of operation are shown. Each one represents at least one commercial instrument. Some of them are available in several modified forms. Iml The Bristol Co. Bubbler fixture &Air supply Either method can DXAPHRAQM ACTUATED INDICATOR. Can be used with BUBBLER TYPE RECORDER measures height E. can any kind of liquid, whether it be flowing, turbulent, or be used with a11 kinds of liquids, including those carry- carrying solid matter. Recorder can be mounted above or ing solids. Small amount of air is bled into submerged belnw the level of the tank or reservoir. pipe. Gage measures pressure of air that displaces fluid. BELLOWS ACTUATED INDICATOR. Two bellows and connecting tubing are fllled with incompressible fluid. Change in liquid level 'displaces transmitting bellows and pointer. I I i L/,51 Use terminol5 forpumpdown, terminal 3 for ourno-uo control f ELECTRICAL TYPE LEVEL CONTROLLER. Positions of probes determine duration of pump operation. When liquid touches upper probe, relay operates and puinp stops. Through auxiliary contacts, lower pmbe Pro- vides relay holding cdrrent until liquid drops below It. op-ociing switch To float in ion& Minneapolis - Honeywell FLOAT-SWITCH TYPE CONTROL- LEX. When liquid reaches predeter- mined level, float actuates switch through horseshoe-shape arm. Switch can operate valve or pump, as required. c, / - - ___ AUTOMOTIVE TYPE LIQUID LEVEL INDICATOR. Indicator and tank Unit are connected by a single wire. As liquid level in tank increases, brush contact on tank rheostat moves to the rlght, introducing an increasing amount of resistance into circuit that grounds the "F" coil. Displacement of needle from empty mark Is proportional to the amount of resistance introduced into this circuit. Creative Assemblies 27-1 7 Recorder Counterweigh f 'rope yoot float chamber Minmaplis Mneywell FLOAT TYPE RECORDER. MAGNETIC LIQUID LEVEL CONTROLLER. DIFFERENTIAL PRESSURE SYSTEM. Pointer can be attwhed to a When liquid level is normal, common-to-right Applicable to liquids under pressure. calibrated float tape to give Measuring element is mercury manometer. an approximate hstantane- level drops to predetermined level. magnetic Mechanical or electric meter body can be ous indication of fluld level. Piston is drawn below the magnetic field. used. Seal pots protect meter body. leg circuit of mercury switch is closed. When t of ocfuofing, Pressure gouge e r-7 element , -_ PA Seof required fw corrosive or viscous fluiUs Mimqoofis- HmRywrll DIRECT READING FLOAT TYPE GAGE. Inexpensive, direct-reading gage has dial calibruted to tank volume. Comparable type as far as simplicity Is concerned has needle connected through a right-angle arm to float. As liquid level drops, float rotates the arm and the needle. PRESSURE UAUE INDICATOR for open vessels. Pressure of liquid head is imposed directly upon actuating element of pressure gage. Center line of the actuating element must conincide wlth the minimum level line if the gage is to read zero when the liquid reaches the minlhum level. Heoter wire- Bimetal strip - - 7, BIMETALLIC TYPE INDICATOR. When tank is empty, contacts in tank unit just touch. With switch closed, heaters cause both bimetallic strips to bend. This opens contacts in tank and bimetals cool, closing circuit again. Cycle repeats about once per sea As Hqutd level increases. float forces cam to bend tank bimetal. Action is simllar to previous case, but current and needle displacement are increased. rank -Float SWITCH ACTUATED LEVEL CON- TROLLER. Pump is actuated by switch. Float pivots magnet 40 that upper pole attracts switch contact. Tank wall serves as other contact. 27-18 Hangers Put Up by Hand No tools needed to install these hangers made of wire, rod or bar-stock. L. Kasper CLIP is most secure when tubing of right size helps keep it spread. To install, hook one side over edge of slot and spring in other side. EDGE HANGER doesn’t have to be sprung, but requires enough clearance above holes so that ends can be pushed down through. RAMPS cam split end together as hanger is pushed into slot. Ends spread again when notches engage sheet. Small end enters large slot first, then tilts over into smaller, close-fitting slot. Creative Assemblies 27- 19 LOOP hooks over bar and is held secure by short tail which snaps into hole drilled through the side. COIL grips edges of T- or I-section or flat bar. Spreading the ends wraps wire tightly around tubing to prevent vibration. DOUBLE HANGER supports two tubes 8s they pass through divider. While tubes are in place hanger can’t come out. 8 END PIECE supports pipe between waUs of any thickness. First spring it over pipe, then slide it along pipe into holes. 27-20 Assemble Sheetmetal with Sheetmetal These sheetmetal parts join sheetmetal quickly with the simplest of tools. L. Kasper SQUEEZE CLIP holds two overlapping sheets together. The ends of the clip are pushed through parallel slots, then bent over much like a staple. ALIGNING PIECE slides up out of the way in long slot while butting sheets are being positioned. Afterwards it slips down over lower sheet. CUP carries a bar on both sides of divider. Here bars stick up above the top, but deeper cutout will lower them until they are flush or sunk. ESS supports shelf between uprights, By mating with notched edge it acts as a key to keep shelf from sliding back and forth. and provides positive location, [...]... Figure 3 41 ILLUSTRATED SOURCEBOOK of MECHANICAL COMPONENTS S E C T I O N 28 DESIGN Volume and CG Equations 28-2 Common Area of Intersecting Circles 28-10 Compound Angles 28-12 Calculation of Dihedral Angles 28- 15 Frustums of Cones 28- 18 Length of Material for 90-Degree Bends 28- 19 8 Simple Methods to Measure Moment of Inertia 28-20 Friction Wheel Drives Designed for Maximum Torque 28-22 Radii of Gyration... tension, in lb per sq in R = radius of driven pulley, in in L = length of tight p a r t of belt which is clear of t h e pulley, in in Design Formulas 26 Effect of the Flexibility of Flywheel Spokes on WE 2of -.-The effective WR 2of the rim is WR2 = (WR2)' (WR2)'f2 1 - 9.775c where (WR2)' = flywheel effect of the rim j = natural torsional frequency of t h e system of which t h e flywheel is a member,... to line of spring force, in p = perpendicular distance from line of wheel centers to center of axle, in G = resultant of motor weight, driving wheel weight, and subbase weight, referred to axis of the motor, Ib g = horizontal distance from center of axle to vertical line passing through axis of motor, in f = perpendicular distance from tangent through point of contact of wheel faces to center of axle,... effect of the driven mass at the driving shaft is wR2 = h2(WR2)’ (WR2)lf2 19.775c Drivinu pulley where h = R I / R - r.p.m of pulley belted t o shaft r.p.m of shaft (WR2)’ = flywheel effect of t h e driven body a b o u t its own axis of rotation f = natural torsional frequency of t h e system, in vibrations per sec C = R2AE/L A = cross-sectional area of belt, in sq in E = modulus of elasticity of belt... rod L1 = distance from t h e center line of t h e crank- + pin t o t h e center of gravity of t h e connecting rod 23 Mass Geared to a Shaft.-The equivalent flywheel effect at the shaft in question is W R 2 = h2(WR2)’ (WRz)’ = flywheel effect of t h e body in question where h = gear ratio - r.p.m of mass geared t o shaft r.p.m of shaft about i t s own axis of rotation 24 Mass Geared to Main Shaft and... -Driven gear effect of the mass (WR2)’a t the position of the driving gear on the main shaft is WR2 = h2(WR2)‘ ( WR2)‘f2 1‘\‘Driving gear where h = gear ratio - r.p.m of driven gear r.p.m of driving gear (WR2)‘ = flywheel effect of geared-on mass 26 Belted Drives.-The L c +! 9.775c f = natural torsional frequency of t h e shafting C system, i n vibrations per sec = torsional rigidity of flexible connecting... Complete Torus Volume WR',, r2Dr2 a2pDr2 = (D2 4 = ~ + 3r2) 12 Outside Part of a Torus Volume = 2x7-2 9- WR2,-, = wpr2 t$+ r) [ 4E t 2 + 4r) + r 2 g D + -15 D r 28-27 28-28 13 Inside Part of a Torus 14 Circular Segment about an Axis through Center of Circle p - c _+TI C 2R a = 2 sin-' - deg Area (a)Any material: WR2,-, = pT R 2cY C2 - 'JR2 114. 59 2 = _ [m- $ (3R2 - 3)c J R 2 R c2 5 4~ (b) For steel: WR2,-,... 28-29 28-30 22 WR 2of a Connecting Rod, Effective at the Cylinder Center Line, about the Crankshaft Center Line W R = r2 ~ [w1+ w2( + &)] ; where r = crank radius L = center-to-center length of connecting rod W1 = weight of t h e lower or rotating p a r t of t h e rod = [W& - LI)]/L W 2 = weight of t h e upper or reciprocating p a r t of t h e rod = WRLJL W R = W1 Wz,t h e weight of t h e complete rod... the face of the driven wheel As the driving wheel drops to a lower position, the cosine of the angle included between the line of centers of the axle and motor and the horizontal centerline of the slide rods increases, thus compressing the spring F and increasing the contact force P With an increasing load torque, the driving wheel will finally fall away from the driven wheel At the instant of last... Formulas WR2 OF SYMMETRICAL BODIES For computing WR 2of rotating masses of weight per unit volume p , by resolving t h e body into elemental shapes See page 208 for effect of W R 2on electric motor selection Nole: P in pounds per cubic inch and dimensions in inches give W E 2in 1b.-in squared 1 Weights per Unit Volume of Materials WEIGHT, LB MATERIAL PER Cast iron Cast-iron castings of heavy section . > t-Away View of Rotary Piston Engine 42 Figure 3 41 ILLUSTRATED SOURCEBOOK of MECHANICAL COMPONENTS SECTION 28 DESIGN Volume and CG Equations 28-2 Common Area of Intersecting. of mercury switch is closed. When t of ocfuofing, Pressure gouge e r-7 element , -_ PA Seof required fw corrosive or viscous fluiUs Mimqoofis- HmRywrll DIRECT READING FLOAT. Draftsman Exploded drawing of engine illustrates the many standard mechanical components that are arranged to preform a function in a new way. 27-24 End View of Rotary Piston Engi Figure