Assembly Automation and Product Design, Second Edition

1574446436......Page 1
Preface......Page 8
The Author......Page 10
Table of Contents......Page 12
Introduction......Page 20
1.1 Historical Development of the Assembly Process......Page 21
1.2 Choice of Assembly Method......Page 25
1.3 Social Effects of Automation......Page 29
References......Page 34
2.2 Intermittent Transfer......Page 36
2.3 Indexing Mechanisms......Page 42
2.4 Operator-Paced Free-Transfer Machine......Page 46
References......Page 47
3.1 Mechanics of Vibratory Conveying......Page 48
3.3 Effect of Track Acceleration......Page 53
3.5 Effect of Track Angle......Page 54
3.6 Effect of Coefficient of Friction......Page 56
3.7 Estimating the Mean Conveying Velocity......Page 57
3.8 Load Sensitivity......Page 61
3.9 Solutions to Load Sensitivity......Page 63
3.10 Spiral Elevators......Page 65
3.12 Orientation of Parts......Page 66
3.13 Typical Orienting System......Page 67
3.14 Effect of Active Orienting Devices on Feed Rate......Page 73
3.15 Analysis of Orienting Systems......Page 74
3.15.1 Orienting System......Page 76
3.15.2 Method of System Analysis......Page 77
3.15.3 Optimization......Page 80
3.16.1 Analysis......Page 82
3.17 Natural Resting Aspects of Parts for Automatic Handling......Page 88
3.17.1 Assumptions......Page 89
3.17.2 Analysis for Soft Surfaces......Page 90
3.17.3 Analysis for Hard Surfaces......Page 96
3.18 Analysis of a Typical Orienting System......Page 97
3.18.1 Design of Orienting Devices......Page 104
3.19 Out-of-Bowl Tooling......Page 106
References......Page 108
Automatic Feeding and Orienting - Mechanical Feeders......Page 110
4.1 Reciprocating-Tube Hopper Feeder......Page 111
4.2.1 Maximum Track Inclination......Page 113
4.2.2 Load Sensitivity and Efficiency......Page 118
4.3 Reciprocating-Fork Hopper Feeder......Page 119
4.4.1 Feed Rate......Page 121
4.4.2 Load Sensitivity and Efficiency......Page 125
4.5.1 Indexing Rotary-Disk Feeder......Page 127
4.5.2 Rotary-Disk Feeder with Continuous Drive......Page 128
4.6 Centrifugal Hopper Feeder......Page 129
4.6.1 Feed Rate......Page 130
4.6.2 Efficiency......Page 133
4.7.1 Design of the Hook......Page 134
4.7.2 Feed Rate......Page 137
4.9 Tumbling-Barrel Hopper Feeder......Page 138
4.9.1 Feed Rate......Page 140
4.11 Magnetic-Disk Feeder......Page 143
4.12 Elevating Hopper Feeder......Page 144
4.14 Magazines......Page 145
References......Page 149
5.1 Gravity Feed Tracks......Page 150
5.1.1 Analysis of Horizontal-Delivery Feed Track......Page 151
5.1.2 Example......Page 156
5.1.3 On/Off Sensors......Page 158
5.1.3.1 Theory......Page 159
5.1.4 Feed Track Section......Page 162
5.1.5.1 Analysis......Page 165
5.1.5.2 Results......Page 172
5.2 Powered Feed Tracks......Page 177
5.2.1 Example......Page 179
5.3 Escapements......Page 180
5.3.1 Ratchet Escapements......Page 181
5.3.2 Slide Escapements......Page 183
5.3.3 Drum Escapements......Page 184
5.3.5 Jaw Escapements......Page 186
5.4 Parts-Placing Mechanisms......Page 187
5.5.1 Terminology......Page 190
5.5.2 Advantages of Robot Assembly......Page 191
5.5.3 Magazines......Page 193
5.5.5 Automatic Feeders for Robot Assembly......Page 194
5.5.6 Economics of Part Presentation......Page 197
5.5.7 Design of Robot Assembly Systems......Page 201
References......Page 205
6.1.1 Effect of Parts Quality on Downtime......Page 206
6.1.2 Effects of Parts Quality on Production Time......Page 207
6.1.3 Effect of Parts Quality on the Cost of Assembly......Page 209
6.2 Free-Transfer Machines......Page 214
6.2.1 Performance of a Free-Transfer Machine......Page 215
6.2.3 Number of Personnel Needed for Fault Correction......Page 219
6.3 Basis for Economic Comparisons of Automation Equipment......Page 220
6.3.1 Basic Cost Equations......Page 221
6.4.1 Indexing Machine......Page 223
6.4.3 Effect of Production Volume......Page 224
6.5 Economics of Robot Assembly......Page 226
6.5.1 Parts Presentation......Page 227
6.5.2 Profile of Typical Candidate Assembly......Page 230
6.5.3.1 Equipment Costs......Page 231
6.5.3.3 Parts Quality......Page 232
6.5.3.4 Basic Cost Equation......Page 233
6.5.4.1 Equipment Costs......Page 234
6.5.4.2 Cost Equation......Page 235
References......Page 236
7.2 Where Design for Assembly Fits in the Design Process......Page 238
7.3.1 Design Guidelines for Part Handling......Page 240
7.3.2 Design Guidelines for Insertion and Fastening......Page 241
7.4 Development of a Systematic DFA Analysis Method......Page 246
7.5 DFA Index......Page 248
7.6 Classification System for Manual Handling......Page 249
7.7 Classification System for Manual Insertion and Fastening......Page 252
7.8 Effect of Part Symmetry on Handling Time......Page 255
7.9 Effect of Part Thickness and Size on Handling Time......Page 256
7.10 Effect of Weight on Handling Time......Page 258
7.13 Threaded Fasteners......Page 259
7.15 Problems with Manual Assembly Time Standards......Page 261
7.16 Application of the DFA Method......Page 263
7.16.1 Results of the Analysis......Page 267
7.17 Further General Design Guidelines......Page 270
References......Page 273
8.1 Introduction......Page 276
8.2 Design of Parts for High-Speed Feeding and Orienting......Page 277
8.3 Example......Page 282
8.4 Additional Feeding Difficulties......Page 284
8.5 High-Speed Automatic Insertion......Page 285
8.6 Example......Page 288
8.7 Analysis of an Assembly......Page 290
8.8 General Rules for Product Design for Automation......Page 291
8.9 Design of Parts for Feeding and Orienting......Page 295
8.10.2 Rules for the Design of Parts......Page 299
8.11 Product Design for Robot Assembly......Page 300
8.11.1 Summary of Design Rules for Robot Assembly......Page 306
References......Page 308
9.2 Terminology......Page 310
9.3 Assembly Process for PCBs......Page 311
9.4 SMD Technology......Page 320
9.5 Estimation of PCB Assembly Costs......Page 321
9.6.1 Instructions......Page 322
9.7 PCB Assembly - Equations and Data for Total Operation Cost......Page 324
9.7.3 Robot Insertion Machine......Page 325
9.8 Glossary of Terms......Page 327
References......Page 329
Feasibility Study for Assembly Automation......Page 330
10.1 Machine Design Factors to Reduce Machine Downtime Due to Defective Parts......Page 331
10.2 Feasibility Study......Page 332
10.2.1 Precedence Diagrams......Page 333
10.2.2 Manual Assembly of Plug......Page 336
10.2.3 Quality Levels of Parts......Page 337
10.2.4 Parts Feeding and Assembly......Page 338
10.2.5.1 Indexing Machine......Page 340
10.2.5.2 Free-Transfer Machine......Page 343
10.2.6 Robot Assembly of the Power Plug......Page 345
References......Page 351
Problems......Page 352
A.1 The Method......Page 382
A.2 Analysis......Page 384
A.4 Discussion......Page 385
Reference......Page 387
Appendix B Out-of-Phase Vibratory Conveyors......Page 388
B.1 Out-of-Phase Conveying......Page 389
B.2 Practical Applications......Page 391
Reference......Page 392
C.1.3 Procedure......Page 394
C.1.4 Theory......Page 395
C.1.5 Presentation of Results......Page 397
C.2.2 Equipment (Objective 1)......Page 398
C.2.3 Theory (Objective 1)......Page 399
C.2.6 Equipment (Objective 2)......Page 400
C.2.8 Procedure (Objective 2)......Page 401
C.2.10 Conclusions......Page 402
D.1 Coding System......Page 404
Envelope......Page 405
Features......Page 406
Rotational Symmetry......Page 407
Example 1......Page 409
Example 3......Page 410
D.1.3 Sample Parts for Practice......Page 411
Example 3: Code No. 220......Page 412
Example 6: Code No. 685......Page 413
D.1.5 Coding System for Small Parts......Page 414
Small Parts for Automatic Handling (Choice of the first digit)......Page 416
Rotational Parts (Parts with a first digit of 0, 1, or 2)......Page 418
Triangular and Square Parts (Parts with a first digit of 3, 4, or 5)......Page 419
Triangular and Square Parts (Parts with a first digit of 3, 4, or 5)......Page 420
Triangular and Square Parts (Parts with a first digit of 3, 4, or 5) (continued)......Page 421
Rectangular Parts (Parts with a first digit of 6, 7, or 8)......Page 422
Rectangular Parts (Parts with a first digit of 6, 7, or 8)......Page 423
Difficult-to-Feed Parts (parts with a first digit of 9)......Page 425
Difficult-to-Feed Parts (parts with a first digit of 9)......Page 426
D.2 Feeding and Orienting Techniques......Page 427
D.3 Orienting Devices for Vibratory-Bowl Feeders......Page 493
D.4 Nonvibratory Feeders......Page 511
Nomenclature......Page 520
C......Page 526
F......Page 527
M......Page 528
P......Page 529
S......Page 530
W......Page 531