Design Handbook

Design Handbook Engineering Guide To SpringDesign 1987 Edition

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Table of Contents

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section

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Eor to Use the Handbook

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Selccdng Spring Configurations hrsh. Pull. Twist or Energy Stofage Applications: CommonAvailable Configurations.

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3

Spring Materials Common Specifications,Elastic Modulus, Magnetic Characteristics,Heat Treatment, Stress Relaxation, Corrosion, Coatingsand Finishes.SpringWire: Tensile Properties,Cost and Availability. Sprine Strip: Strength,Formability and Edge Condition. Reidual Stress, Fatigue and Reliability Load-CarryingAbility, FatigueTerminology, Modified GoodmanDiagram, Weibull Analysis, Load Loss. Eelical Compression Springs GeneralDefinitions, Squareness,Parallelism, Hysteresis,Design Equationsfor Spring Rate and Stress,Bucklinl Choice of Operating Stress for Static and Cyclic Applications, Dynamic Loading Impict and Resonance, RectangularWire, StrandedWire, Variable Diameter, Variable Pitch and Nested Springs,CommercialToleranc, Hot-Wound Springs DesignConsiderations,End Configurations, Materials, Choice of Operating Stress,Tolerances. Eelirnl Extension Springs Initial Tension, Types of Ends and Dimensions, Design Equations,Choice of OperatingStressfor Static and Cyclic Applications, Commercial Tolerances.

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Garter Springs Joint Design, Design Equationsand Tolerances.

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Helical Torsion Springs Mean Diameter, Length, Design Equations for Rate and Stress,End Configurations,Natural Frequency,Choice of Operating Stress for Static and Cyclic Applications, Double Torsion and Rectangular Wire Springs, ioleranc,

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f,staining Rings External and Internal Types, Ends, Design Equations, Choice of StressLevel, Tolerances. Belleville Spring Washers Load-Deflection Characteristics,Mounting, Design Equations.Choiceof StressLevel for Static and Cyclic Applications, Stackingand Tolerances.

12

Flat Springs . . Design Considerationsand Equations for Cantilever and Simple Beams, Choice of StressLevel and Tolerances.

13

Specid Spring Washers Design Considerationsand Equations for Curved, Wave and Finger Washers, Choice of StressLevel and Tolerances.

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Power Springs GeneralDesign Considerationsand Equations, OperatingStressfor Power and hestressed Power Springs.

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Constant Force Springs Extension Type_,Design Equations, Mounting and Tolerances,Motor Type Design Equations for "A" and "B" Type Motors, OperatingStress and Tolerances.

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Spird Springs Design Equations for Hair Springsand Brush Springs.

17

Volute Springs Design Equations and Choice of Operating Stress Level.

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Wire Forms GeneralInformation and How to Specify.

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IndexandReferencelnformation .......1 Glossary of Spring Terminology, Bibliography, Trademarks, Conversion Factors, Abbreviations and Symbols, HardnessScaleConversions,Index and Lists of Thblesand Illustrations.

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SelectingSpring Configurations Tabb 2-1. Spring Configurations. T\'PT.

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COTNCUNATION

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Helical Compression Round and Recrangular \t-ire

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(Section 12) hrsh or pull-wide range of loads, low deflection range.

Cantilever, RectangularSection

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Push-wide load and deflection range-constant rate'

Constant Pitch

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Barrel

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Push-wide load and deflection range. Conical spring can be made with minimum solid height and with constantor increasing rate. Barrel, hourglass,and variable-pitchspringsused to minimize resonant surging and vibration.

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Hourglass

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Helical Torsion (Section9)

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Spiral (Section16)

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Spring Washer

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Belleville

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Volute

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Hairspring

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Brush Push-high loads, low deflections-choice of rates (constant, increasing, or decreasing).

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