Design of Brakes and Clutches · Machine Design · GATE ME

Marks 1

The braking system shown in the figure uses a belt to slow down a pulley rotating in the clockwise direction by the application of a force P. The belt wraps around the pulley over an angle α = 270 degrees. The coefficient of friction between the belt and the pulley is 0.3. The influence of centrifugal forces on the belt is negligible.

During braking, the ratio of the tensions T₁ to T₂ in the belt is equal to __________. (Rounded off to two decimal places)

Take π = 3.14.

GATE ME 2023

Which one of the following CANNOT impart linear motion in a CNC machine?

GATE ME 2022 Set 2

A square threaded screw is used to lift a load W by applying a force F. Efficiency of square threaded screw is expressed as

GATE ME 2022 Set 1

A single – plate clutch has a friction disc with inner and outer radii of $$20mm$$ and $$40$$ $$mm,$$ respectively. The friction lining in the disc is made in such a way that the coefficient of friction $$\mu $$ varies radially as $$ = 0.01\,r,$$ where $$r$$ is in $$mm.$$ The clutch needs to transmit a friction torque of $$18.85$$ $$kN.mm.$$ As per uniform pressure theory, the pressure (in $$MPa$$) on the disc is ___________________.

GATE ME 2017 Set 2

The force $${F_1}$$ and $${F_2}$$ in a brake band and the direction of rotation of the drum are as shown in the figure. The coefficient of friction is $$0.25.$$ The angle of wrap is $$3\pi /2$$ radians. It is given that $$R=1$$ $$m$$ and $${F_2} = 1N.$$ The torque (in $$N-m$$) exerted on the drum is ____________

GATE ME 2016 Set 2

For the brake shown in the figure, which one of the following is TRUE?

GATE ME 2016 Set 2

A disc clutch with a single friction surface has coefficient of friction equal to $$0.3.$$ The maximum pressure which can be imposed on the friction material is $$1.5$$ $$MPa.$$ The outer diameter of the clutch plate is $$200$$ $$mm$$ and its internal diameter is $$100$$ $$mm.$$ Assuming uniform wear theory for the clutch plate, the maximum torque (in $$N.m$$) that can be transmitted is ___________.

GATE ME 2014 Set 2

A clutch has outer and inner diameters $$100mm$$ and $$40mm$$ respectively. Assuming a uniform pressure of $$2MPa$$ and coefficient of friction of inner material $$0.4,$$ the torque carrying capacity of the clutch is

GATE ME 2008

A disk clutch is required to transmit $$5$$ $$kW$$ at $$2000$$ $$rpm$$ the disk has a friction lining with Coefficient of friction equal to $$0.25.$$ Bore radius of friction lining is equal to $$25mm.$$ Assume uniform contact pressure of $$1MPa.$$ The value of outside radius of the friction lining is

GATE ME 2006

Axial operation claw clutches having self-locking tooth profile

GATE ME 1987

Marks 2

A solid massless cylindrical member of 50 mm diameter is rigidly attached at one end, and is subjected to an axial force $P = 100$ kN and a torque $T = 600$ N.m at the other end as shown. Assume that the axis of the cylinder is normal to the support.

Considering distortion energy theory with allowable yield stress as $300$ MPa, the factor of safety in the design is _____ (rounded off to 1 decimal place).

GATE ME 2024

A band brake shown in the figure has a coefficient of friction of 0.3. The band can take a maximum force of 1.5 kN. The maximum braking force (F) that can be safely applied is _______ N (rounded off to the nearest integer).

GATE ME 2024

A shaft AC rotating at a constant speed carries a thin pulley of radius r = 0.4 m at the end C which drives a belt. A motor is coupled at the end A of the shaft such that it applies a torque M, about the shaft axis without causing any bending moment. The shaft is mounted on narrow frictionless bearings at A and B where AB = BC = L = 0.5 m. The taut and slack side tensions of the belt are T₁ = 300 N and T₂ = 100 N, respectively. The allowable shear stress for the shaft material is 80 MPa. The self-weights of the pulley and the shaft are negligible. Use the value of π available in the on-screen virtual calculator. Neglecting shock and fatigue loading and assuming maximum shear stress theory, the minimum required shaft diameter is mm (round off to 2 decimal places).