Page 440 - Marks Calculation for Machine Design
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P2: Sanjay
        P1: Shibu/Rakesh
        Brown.cls
                                      15:34
                          January 4, 2005
                 Brown˙C10
                  422
                    For the slider-crank linkage shown in Fig. 10.13, the crank angle (φ) is zero.
                                      f    APPLICATION TO MACHINES
                                  B
                                                  L
                                L AB              BC
                                       90°
                                 A                b         C
                                                            ◦
                                FIGURE 10.13  Slider-crank linkage at φ = 0 .
                    From Eq. (10.12) the angle (β) becomes

                                           L AB               L AB
                                                        ◦
                                                    ◦
                              sin β| φ = 0 ◦ =  sin(90 − 0 ) =    sin 90 ◦
                                           L BC              L BC
                                                                              (10.24)
                                         L AB
                                       =
                                         L BC
                  and from Eq. (10.10) the angular velocity of the connecting rod (ω rod ) becomes
                                                        ◦
                                               L AB  sin 0
                                   ω rod | φ=0 ◦ =         ω crank = 0        (10.25)
                                              L BC   cos β
                  and from Eq. (10.11) the velocity of the slider (v slider ) becomes
                                                               ◦
                                                         ◦
                                 v slider | φ=0 ◦ = (L AB ω crank )(cos 0 + sin 0 tan β)
                                                                              (10.26)
                                          = L AB ω crank
                  and from Eq. (10.22) the angular acceleration of the connecting rod (α rod ) becomes
                                          2
                                                 ◦
                                    L AB  ω crank  cos 0 + α crank sin 0 ◦
                          α rod | φ=0 ◦ =                      − ω  2    ◦ tan β
                                                                  rod φ=0
                                   L BC          cos β
                                          2
                                    L AB  ω crank  2
                                 =             − (0) tan β                    (10.27)
                                   L BC  cos β
                                          2
                                    L AB  ω crank
                                 =
                                   L BC  cos β
                  and from Eq. (10.23) the acceleration of the slider (a slider ) becomes
                                   	  2     ◦      ◦               ◦      ◦
                      a slider | φ=0 ◦ = L AB ω crank (sin 0 − cos 0 tan β) − α crank (cos 0 + sin 0 tan β)

                                + L BC ω  2    ◦ (cos β + tan β sin β)
                                      rod φ=0
                                   	   2
                              = L AB −ω                                       (10.28)
                                       crank  tan β − α crank
                                        2
                                + L BC (0) (cos β + tan β sin β)
                                     	  2
                              =−L AB ω
                                       crank  tan β + α crank
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