Engineering Mechanics

Chapter 11 : Simple Lifting Machines „„„„„ 189 Example 11.3. The larger and smaller diameters of a differential wheel and axle a ...

(^190) „„„„„ A Textbook of Engineering Mechanics Example 11.5. In a differential wheel and axle, the diameter of the effort whee ...

Chapter 11 : Simple Lifting Machines „„„„„ 191 We know that displacement of the effort in one revolution of the upper pulley blo ...

(^192) „„„„„ A Textbook of Engineering Mechanics and 1500 M.A. W PP We also know that efficiency, 1500 M.A. 60 0.8 V.R. 25 P P o ...

Chapter 11 : Simple Lifting Machines „„„„„ 193 11.6.GEARED PULLEY BLOCK It is an improved form of a differential pulley block in ...

(^194) „„„„„ A Textbook of Engineering Mechanics Solution. Given: No. of cogs on the effort wheel (T 1 ) = 90; No. of cogs on th ...

Chapter 11 : Simple Lifting Machines „„„„„ 195 If the worm is single-threaded (i.e., for one revolution of the wheel A, the scre ...

(^196) „„„„„ A Textbook of Engineering Mechanics Velocity ratio of the machine We know that velocity ratio of a worm and worm wh ...

Chapter 11 : Simple Lifting Machines „„„„„ 197 We know that distance moved by effort in one revolution of wheel =πD If the worm ...

(^198) „„„„„ A Textbook of Engineering Mechanics We know that velocity ratio of a worm geared pulley block, 400 50 V.R. 200 250 ...

Chapter 11 : Simple Lifting Machines „„„„„ 199 ∴ No. of revolutions made by the load drum = 2 1 T T and distance moved by the lo ...

(^200) „„„„„ A Textbook of Engineering Mechanics Solution. Given: Length of lever (l) = 700 mm; No. of pinion teeth (T 2 ) = 12; ...

Chapter 11 : Simple Lifting Machines „„„„„ 201 11.10.DOUBLE PURCHASE CRAB WINCH A double purchase crab winch is an improved form ...

(^202) „„„„„ A Textbook of Engineering Mechanics ∴ Distance moved by the load 24 13 2 TT r TT =π× × ...(ii) ∴ Distance moved by ...

Chapter 11 : Simple Lifting Machines „„„„„ 203 Solution. Given: Dia of load drum = 160 mm or radius (r) = 100/2 = 80 mm; Length ...

(^204) „„„„„ A Textbook of Engineering Mechanics EXERCISE 11.2 In a differential pulley block, diameters of the concentric pull ...

Chapter 11 : Simple Lifting Machines „„„„„ 205 In a single purchase crab winch, length of the handle is 160 mm and the gear rat ...

(^206) „„„„„ A Textbook of Engineering Mechanics 11.12. FIRST SYSTEM OF PULLEYS In Fig. 11.11 is shown the first system of pulle ...

Chapter 11 : Simple Lifting Machines „„„„„ 207 ∴ Efficiency, M.A. 6.4 0.80 80% V.R. 8 η= = = =^ Ans. Amount of friction We know ...

(^208) „„„„„ A Textbook of Engineering Mechanics A little consideration will show, that for x displacement of the weight, the ef ...