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4-2 Determine the type of the linkage and the type of the two side links AB and DC (crank or rocker) according to the Grashof criterion. Can the coupler BC rotate 360 o with respect to other links (Yes or No)?.
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4-2 Determine the type of the linkage and the type of the two side links AB and DC (crank or rocker) according to the Grashof criterion. Can the coupler BC rotate 360o with respect to other links (Yes or No)?
4-3 In a revolute four-bar linkage ABCD, LBC=100mm, LDC =80mm, LAD=110mm. (1)Find the range of the values for the length LAB of link AB if the linkage is either (a) a crank-rocker mechanism with crank AB, or (b) a double-rocker mechanism. (2) Can the linkage be a double-crank mechanism by choosing LAB suitably? Why?
4-4 If the side link AB is a driver and rotates at a constant speed,(a) find the pressure angle and the transmission angle of the mechanism at that position.
(b) find the angular stroke max of the link DC. (e) find the crank acute angle between the two limiting positions.(f) calculate the time ratio k .
(c) will any dead-point occur during the whole cycle of the motion?(d) find the maximum pressure angle max and the minimum transmission angle min.
(3) If the side link DC is a driver,(a) find the pressure angle ’ and the transmission angle ’ of the mechanism at that position.
(b) will any dead-point occur during the whole cycle of the motion? If so, when?(c) find the maximum pressure angle max and the minimum transmission angle min.
4-5 In the offset slider-crank mechanism shown in Fig.4-5, the driver crank AB rotates at a constant speed. Let LAB=120mm, LBC=250mm, offset e=60mm, and AB=60o. Find
(1)the length of stroke H of the slider, (2) the crank acute angle (3) the time ratio k ,
4-10 Shown in Fig.4-47 are the two positions, B1C1 and B2C2, of the coupler BC of a revolute four-bar linkage ABCD. The link AB is a driver. The pressure angle at the first position is 0o. The second position of the mechanism is a toggle position. Design the linkage.
The locus of the point B relative to the frame is a circle the centre of which is the fixed pivot A, the fixed pivot A must be located on the bisector of B1B2.Similarly,D must be located on the bisector of C1C2.
The link AB is a driver. The pressure angle at the first position is 0o.