上海交通大学：《工程学导论》课程教学资源（讲义）Technical knowledge_3spring

Machine Components Introduction to Engineering

1 Introduction to Engineering Machine Components

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2 Introduction to Engineering Springs Springs

What Is Spring? Springs > Elastic parts > Exert forces,or torques Absorb energy,which is usually stored and later released Introduction to Engineering

3 Introduction to Engineering What Is Spring? Springs  Elastic parts  Exert forces, or torques  Absorb energy, which is usually stored and later released

Type of Springs Torsion Bar Spring Helical Compression Spring Helical Extension Spring ■Torsion Springs Introduction to Engineering

4 Introduction to Engineering Type of Springs  Torsion Bar Spring  Helical Compression Spring  Helical Extension Spring  Torsion Springs

Torsion Bar Spring >The simplest >Common applications include some automotive suspension springs,and counterbalancing springs for car hoods and trunk lids,where small torsion bars fit near the hinges Fixed end Bearing Spline Torsion bar portion Generous radius Bearing Spline 5 Introduction to Engineering

5 Introduction to Engineering Torsion Bar Spring The simplest Common applications include some automotive suspension springs, and counterbalancing springs for car hoods and trunk lids, where small torsion bars fit near the hinges

Helical Compression Spring >Automatic "over-load stop >A broken compression spring may continue to provide a "stop"that holds the end plates apart FD End surface ground flat 6 Introduction to Engineering

6 Introduction to Engineering Helical Compression Spring Automatic “over-load stop” A broken compression spring may continue to provide a “stop” that holds the end plates apart

Helical Extension Springs Extension springs do not have the automatic "over- load stop”feature. A sufficient static overload can elongate any extension spring to failure. Compression springs are generally preferred to extension springs in safety critical applications. Introduction to Engineering

7 Introduction to Engineering Helical Extension Springs Extension springs do not have the automatic “over￾load stop” feature. A sufficient static overload can elongate any extension spring to failure. Compression springs are generally preferred to extension springs in safety critical applications

Torsion Springs Torsion springs:helical,and spiral Helica/springs:the angular deflection can be several complete turns Long helical springs with many turns usually have a center rod for support. Square or rectangular wire is most efficient for use in helical torsion springs Round wire is often used (usually more available and cost less) 8 Introduction to Engineering

8 Introduction to Engineering Torsion Springs Torsion springs: helical, and spiral. Helical springs: the angular deflection can be several complete turns Long helical springs with many turns usually have a center rod for support. Square or rectangular wire is most efficient for use in helical torsion springs Round wire is often used (usually more available and cost less)

Torsion Springs Spiral springs are used to power clocks and toys. Spiral springs are usually made of thin rectangular wire. Thickness =h 中5时时寸 9 Introduction to Engineering

9 Introduction to Engineering Torsion Springs Spiral springs are used to power clocks and toys. Spiral springs are usually made of thin rectangular wire