Question

Compare and contrast spur, helical, spiroid, hypoid, spiral, bevel and worm gears. What are the advantages/disadvantages of each? When and/or where would you use each type? There are 5 types of clutches. List them, and compare/contrast, listing the application uses for each type. Explain the two types of brakes - disc and drums. Which is more susceptible to changes in coefficient of function and why? Look at these two examples of couplings. Which of these is more suitable for a servo-drive attached to a ball screw on a positioning systems.

Answer 1

Crear & On the basis of axis of Shaft are classified as: - () parallel Axis (a) spur Gear - Straight - cut gears with teeth Projecting radially. Advantage ti) High Power transmission efficiency. (in offer constant velocity ratio. Disadvantage (1) Produce a lot of noise at high speed. (1) They have a limited centre distance. Application - Fuel Pumps, washing Machines, Rolling mills etc., (6) Helical Gears - Teeth are at an angle with the axis of the Shaft. Utos (i) silent operation. (ii) can be used for transferring between non parallel Shafts. tower Disadvantage – (i) efficiency of helical gear is less because of sliding contacts. (i) Generates large amount of thaust. Painting industries , earth moving industries. Application -

Out (11) Non intersecting Non parallel Bevel Gear – bearing exes of the two Shafts intersect and the tooth faces of the gears themselves are conically shaped. Advantage - (i) It makes (1) Rotational be changed possible to change operating angle drive and torque of the second wheel can in relation to the first pisadvantage – (1) must be precisely mounted for better operation. (1) The beaning must be capable of supporting significant forces. Aerospace, cement Mills. Application - (6) worm wheet. – near Arrangement in which worm meshes with a worm gear. Advantage - Operate silently and smoothly (ii) They are self locking Disadvantage - Materials are expensive. (ii) worm drives have high power loss, Lifts or - Application: Musical instruments, screw conveyors.

bevel (c) gear spiral gear - with It is a helical bevel teeth. Advantage - (i) Due to spiral teeth it provide uniform and silent teeth engagement. (ii) Power transmitting capacity is more than simple bevel gear Disadvantage - (i) Always replaced in pairs (11) Crears are manufactured in pairs – used for power perpendicwar to transmitting in the shafts which are each other. (vehicle differential) (d) Hypoid Gears - Hypoid Gears are same as spiral bevel gears but the only difference is that center line of both the shafts do not intersect in Hypoid Слео . Advantage – (i) load carrying capacity is more, (ii) High strength. bis advantage - (i) complex design (ii) not suitable for fast speed. used in Differential gears of alltomotive drive systems. Application:

(e) spiroid gear – skew axis Grearing. Advantage –(i) st can supply high torque. (ii) It has igh stiffness. Disadvantage (1) Tooth pressure angles are not symmetrical. (ii) Magnitude of forces on the teeth are different. Application – used where high amounts of torque are required from a small gearbox envelope.
Full detailed solution of quesgion number 1 is explained