机械设计 机器和机构综合与分析 英文版PDF电子书下载

PARTⅠ KINEMATICS OF MECHANISMS 1

Chapter 1 Introduction 1

1.0 Purpose 3

1.1 Kinematics and Kinetics 3

1.2 Mechanisms and Machines 4

1.3 A Brief History of Kinematics 5

1.4 Applications of Kinematics 6

1.5 The Design Process 7

Design,Invention,Creativity 7

Identification of Need 8

Background Research 9

Goal Statement 9

Performance Specifications 9

Ideation and Invention 10

Analysis 11

Selection 12

Detailed Design 13

Prototyping and Testing 13

Production 13

1.6 Other Approaches to Design 14

Axiomatic Design 15

1.7 Multiple Solutions 15

1.8 Human Factors Engineering 15

1.9 The Engineering Report 16

1.10 Units 16

1.11 What's to Come 18

1.12 References 19

1.13 Bibliography 20

Chapter 2 Kinematics Fundamentals 22

2.0 Introduction 22

2.1 Degrees of Freedom 22

2.2 Types of Motion 23

2.3 Links,Joints,and Kinematic Chains 24

2.4 Determining Degree of Freedom 28

Degree of Freedom in Planar Mechanisms 29

Degree of Freedom in Spatial Mechanisms 32

2.5 Mechanisms and Structures 32

2.6 Number Synthesis 33

2.7 Paradoxes 37

2.8 Isomers 38

2.9 Linkage Transformation 40

2.10 Intermittent Motion 42

2.11 Inversion 44

2.12 The Grashof Condition 46

Classification of fne Fourbar Linkage 49

2.13 Linkages of More Than Four Bars 52

Geared Fivebar Linkages 52

Sixbar Linkages 53

Grashof-type Rotatability Criteria for Higher-order Linkages 53

2.14 Springs as Links 54

2.15 Practical Considerations 55

Pin Joints versus Sliders and Half Joints 55

Cantiiever versus Straddle Mount 57

Short Links 58

Bearing Ratio 58

Linkages versus Cams 59

2.16 Motor and Drives 60

Electric Motors 60

Air and Hydraulic Motors 65

Air and Hydraulic Cylinders 65

Solenoids 66

2.17 References 66

2.18 Problems 67

Chapter 3 Graphical Linkage Synthesis 76

3.0 Introduction 76

3.1 Synthesis 76

3.2 Function,Path,and Motion Generation 78

3.3 Limiting Conditions 80

3.4 Dimensional Synthesis 82

Two-Position Synthesis 83

Three-Position Synthesis with Specified Moving Pivots 89

Three-Position Synthesis with Alternate Moving Pivots 90

Three-Position Synthesls with Specified Fixed Pivots 93

Position Synthesis for More Than Three Positions 97

3.5 Quick-Return Mechanisms 97

Fourbar Quick-Return 98

Sixbar Quick-Return 100

3.6 Coupler Curves 103

3.7 Cognates 112

Parallel Motion 117

Geared Fivebar Cognates of the Fourbar 119

3.8 Straight-Line Mechanisms 120

Designing Optimum Straight-Line Fourbar Linkages 122

3.9 Dwell Mechanisms 125

Single-Dwell Linkages 126

Double-Dwell Linkages 128

3.10 References 130

3.11 Bibliography 131

3.12 Problems 132

3.13 Projects 140

Chapter 4 Position Analysis 144

4.0 Introduction 144

4.1 Coordinate Systems 146

4.2 Position and Dlsplacement 147

Position 147

Displacement 147

4.3 Translation,Rotation,and Complex Motion 149

Translation 149

Rotation 149

Complex Motion 149

Theorems 150

4.4 Graphical Position Analysis of Linkages 151

4.5 Algebraic Position Analysis of Linkages 152

Vector Loop Representation of Linkages 153

Complex Numbers as Vectors 154

The Vector Loop Equation for a Fourbar Linkage 156

4.6 The Fourbar Slider-Crank Position Solution 159

4.7 An Inverted Slider-Crank Position Solution 161

4.8 Linkages of More Than Four Bars 164

The Geared Fivebar Linkage 164

sixbar Linkages 167

4.9 Position of Any Point on a Linkage 168

4.10 Transmission Angles 169

Extreme Values of the Transmission Angle 169

4.11 Toggle Positions 171

4.12 Circults and Branches in Linkages 173

4.13 Newton-Raphson Solution Method 174

One-Dimensional Root-Findlng(Newton's Method) 174

Multidimensional Root-Finding(Newton-Raphson Method) 176

Newton-Raphson Solution for the Fourbar Linkage 177

Equation Solvers 178

4.14 References 178

4.15 Problems 178

Chapter 5 Analytical Linkage Synthesis 188

5.0 Introduction 188

5.1 Types of Kinematic Synthesis 188

5.2 Precision Points 189

5.3 Two-Position Motion Generation by Analytical Synthesis 189

5.4 Comparison of Analytical and Graphical Two-Position Synthesis 196

5.5 Simultaneous Equation Solution 199

5.6 Three-Position Motion Generation by Analytical Synthesis 201

5.7 Comparison of Analytical and Graphlcal Three-Position Synthesis 206

5.8 Synthesis for a Speclfied Fixed Pivot Location 211

5.9 Center-Point and Circle-Point Circles 217

5.10 Four- and Five-Positlon Analytical Synthesis 219

5.11 Analytical Synthesis of a Path Generator with Prescribed Timing 220

5.12 Analytical Synthesis of a Fourbar Function Generator 220

5.13 Other Linkage Synthesis Methods 224

Precision Point Methods 226

Coupler Curve Equation Methods 227

Optimization Methods 227

5.14 References 230

5.15 Problems 232

Chapter 6 VelocityAnalysis 241

6.0 Introduction 241

6.1 Definition of Velocity 241

6.2 Graphical Velocity Analysis 244

6.3 Instant Centers of Velocity 249

6.4 Velocity Analysis with Instant Centers 256

Angular Velocity Ratio 257

Mechanical Advantage 259

Using Instant Centers in Linkage Design 261

6.5 Centrodes 263

A "Linkless" Linkage 266

Cusps 267

6.6 Velocity of Slip 267

6.7 Analytical Solutions for Velocity Analysis 271

The Fourbar Pin-Jointed Linkage 271

The Fourbar Slider-Crank 274

The Fourbar Inverted Slider-Crank 276

6.8 Velocity Analysis of the Geared Fivebar Linkage 278

6.9 Velocity of Any Point on a Linkage 279

6.10 References 280

6.11 Problems 281

Chapter 7 Acceleration Analysis 300

7.0 Introduction 300

7.1 Definition of Acceleration 300

7.2 Graphical Acceleration Analysis 303

7.3 Analytical Solutions for Acceleration Analysis 308

The Fourbar Pin-Jointed Linkage 308

The Fourbar Slider-Crank 311

Coriolis Acceleration 313

The Fourbar Inverted Slider-Crank 315

7.4 Acceleration Analysisof the Geared Fivebar Linkage 319

7.5 Acceleration of any Point on a Linkage 320

7.6 Human Tolerance of Acceleration 322

7.7 Jerk 324

7.8 Linkages of N Bars 327

7.9 References 327

7.10 Problems 327

Chapter 8 Cam Design 345

8.0 Introduction 345

8.1 Cam Terminology 346

Type of Follower Motion 347

Type of Joint Closure 348

Type of Follower 348

Type of Cam 348

Type of Motion Constraints 351

Type of Motion Program 351

8.2 SVA J Diagrams 352

8.3 Double-Dwell Cam Design—Choosing S VA J Functions 353

The Fundamental Law of Cam Design 356

Simple Harmonic Motion(SHM) 357

Cycloidal Displacement 359

Combined Functions 362

8.4 Single-Dwell Cam Design—Choosing SVA J Functions 374

8.5 Polynomial Functions 378

Double-Dwell Applications of Polynomials 378

Single-Dwell Applications of Polynomials 382

8.6 Critical Path Motion(CPM) 385

Polynomials Used for Critical Path Motion 386

Half-Period Harmonic Family Functions 393

8.7 Sizing the Cam—Pressure Angle and Radius of Curvature 396

Pressure Angle—Roller Followers 397

Choosing a Prime Circle Radius 400

Overturning Moment—Flat-Faced Follower 402

Radius of Curvature—Roller Follower 403

Radius of Curvature—Flat-Faced Follower 407

8.8 Cam Manufacturing Considerations 412

Geometric Generation 413

Manual or NC Machining to Cam Coordinates(Plunge-Cutting) 413

Continuous Numerical Control with Linear lnterpolation 414

Continuous Numerical Control with Circular Interpolation 416

Analog Duplication 416

Actual Cam Performance Compared to Theoretical Performance 418

8.9 Practical Design Considerations 421

Translating or Oscillating Follower? 421

Force- or Form-Closed? 422

Radial or Axial Cam? 422

Roller or Flat-Faced Follower? 423

To Dwell or Not to Dwell? 423

To Grind or Not to Grind? 424

To Lubricate or Not to Lubricate? 424

8.10 References 424

8.11 Problems 425

8.12 Projects 429

Chapter 9 Gear Trains 432

9.0 Introduction 432

9.1 Rolling Cylinders 433

9.2 The Fundamental Law of Gearing 434

The Involute Tooth Form 435

Pressure Angle 437

Changing Center Distance 438

Backlash 438

9.3 Gear Tooth Nomenclature 440

9.4 Interference and Undercutting 442

Unequal-Addendum Tooth Forms 444

9.5 Contact Ratio 444

9.6 Gear Types 447

Spur,Helical,and Herringbone Gears 447

Worms and Worm Gears 448

Rack and Pinion 448

Bevel and Hypoid Gears 449

Noncircular Gears 450

Belt and Chain Drives 450

9.7 Simple Gear Trains 452

9.8 Compound Gear Trains 453

Design of Compound Trains 454

Design of Reverted Compound Trains 456

An Algorithm for the Design of Compound Gear Trains 458

9.9 Epicyclic or Planetary Gear Trains 462

The Tabular Method 464

The Formula Method 469

9.10 Efficiency of Gear Trains 470

9.11 Transmissions 474

9.12 Differentials 477

9.13 References 479

9.14 Problems 479

PART Ⅱ DYNAMICS OF MACHINERY 489

Chapter 10 Dynamics Fundamontals 491

10.0 Introduction 491

10.1 Newton's Laws of Motion 491

10.2 Dynamic Models 492

10.3 Mass 492

10.4 Mass Moment and Center of Gravity 493

10.5 Mass Moment of Inertia(Second Moment of Mass) 495

10.6 Parallel Axis Theorem(Transfer Theorem) 497

10.7 Radius of Gyration 498

10.8 Center of Percussion 498

10.9 Lumped Parameter Dynamic Models 500

Spring Constant 500

Damping 501

10.10 Equivalent Systems 503

Combining Dampers 504

Combining Springs 505

Combining Masses 506

Lever and Gear Ratios 506

10.11 Solution Methods 512

10.12 The Principle of d'Alembert 513

10.13 Energy Methods—Virtual Work 515

10.14 References 517

10.15 Problems 518

Chapter 11 Dynamic Force Analysis 521

11.0 Introduction 521

11.1 Newtonian Solution Method 521

11.2 Single Link in Pure Rotation 522

11.3 Force Analysis of a Threebar Crank-Slide Linkage 525

11.4 Force Analysis of a Fourbar Linkage 531

11.5 Force Analysis of a Fourbar Slider-Crank Linkage 538

11.6 Force Analysis of the Inverted Slider-Crank 541

11.7 Force Analysis—Linkages with More Than Four Bars 543

11.8 Shaking Forces and Shaking Torque 544

11.9 Program FOURBAR 545

11.10 Llnkage Force Analysis by Energy Methods 545

11.11 Controlling Input Torque—Flywheels 548

11.12 A Linkage Force Transmission Index 554

11.13 Practical Considerations 556

11.14 References 557

11.15 Problems 557

11.16 Projects 567

Chapter 12 Balancing 570

12.0 Introduction 570

12.1 Static Balance 571

12.2 Dynamic Balance 574

12.3 Balancing Linkages 579

Complete Force Balance of Linkages 580

12.4 Effect of Balancing on Shaking and Pin Forces 583

12.5 Effect of Balancing on Input Torque 585

12.6 Balancing the Shaking Moment in Linkages 586

12.7 Measuring and Correcting Imbalance 590

12.8 References 591

12.9 Problems 592

Chapter 13 Engine Dynamics 598

13.0 Introduction 598

13.1 Engine Design 600

13.2 Slider-Crank Kinematics 605

13.3 Gas Force and Gas Torque 610

13.4 Equivalent Masses 614

13.5 Inertia and Shaking Forces 617

13.6 Inertia and Shaking Torques 620

13.7 Total Engine Torque 622

13.8 Flywheels 622

13.9 Pin Forces in the Single-Cyllnder Engine 623

13.10 Balancing the Single-Cylinder Engine 631

13.11 Design Trade-offs and Ratios 634

Conrod/Crank Ratio 634

Bore/Stroke Ratio 634

Materials 635

13.12 Bibliography 635

13.13 Problems 635

13.14 Projects 638

Chapter 14 Multicylinder Engines 639

14.0 Introduction 639

14.1 Multicylinder Englne Designs 641

14.2 The Crank Phase Diagram 644

14.3 Shaking Forces in Inllne Engines 646

14.4 Inertla Torque in Inline Engines 649

14.5 Shaking Momentin Inline Engines 650

14.6 Even Firing 652

Two-Stroke Cycle Engine 653

Four-Stroke Cycle Engine 655

14.7 Vee Engine Configurations 661

14.8 Opposed EngineConfigurations 674

14.9 Balanoing Multlcylinder Engines 675

Secondary Balance in the Four-Cylinder Inline Engine 679

14.10 References 682

14.11 Bibliography 682

14.12 Problems 682

14.13 Projects 683

Chapter 15 Cam Dynamics 685

15.0 Introduction 685

15.1 Dynamic Force Analysis of the Force-Closed Cam Follower 686

Undamped Response 686

Damped Response 689

15.2 Resonance 696

15.3 Kinetostatic Force Analysis of the Force-Closed Cam-Follower 698

15.4 Kinetostatic Force Analysis of the Form-Closed Cam-Follower 702

15.5 Camshaft Torque 706

15.6 Measuring Dynamic Forces and Accelerations 709

15.7 Practical Considerations 713

15.8 References 713

15.9 Bibliography 713

15.10 Problems 714

Chapter 16 Engineering Design 717

16.0 Introduction 717

16.1 A Design Case Study 718

16.2 Closure 723

16.3 References 723

Appendix A Computer Programs 725

A.0 Introduction 725

A.1 General Information 727

A.2 General Program Operation 727

A.3 Program FOURBAR 735

A.4 Program FIVEBAR 743

A.5 Program SIXBAR 745

A.6 Program SLIDER 749

A.7 Program DYNACAM 751

A.8 Program ENGINE 757

A.9 Program MATRIX 764

Appendix B Material Properties 765

Appendix C Geometric Properties 769

Appendix D Spring Data 771

Appendix E Atlas of Geared Fivebar Linkage Coupler Curves 775

Appendix F Answers to Selected Problems 781

Index 795

CD-ROM Index 809