Homework 2

 

1) A single-plate clutch transmits a torque of 240 N m. The total spring force acting on the pressure plate is 3360 N and the coefficient of friction of the lining material is 0.3. Calculate the outside diameter of the lining if it had a width of 26 mm. (Assuming uniform wear)

 

2) The friction disc of a single-plate clutch has a face area 0.025 m² and a mean radius of 0.12 m. If the spring exerted a 140 kN/m² pressure on the lining area. The coefficient of friction is 0.35, determine:

a) the torque transmitted

b) the power which can be transmitted at 2500 rev/min.

 

3) A motor vehicle is fitted with a single dry-clutch with external and internal lining diameters of 0.25 m and 0.15 m, respectively. Assuming a coefficient of friction of 0.35, calculate the total spring force necessary to transmit 50 kW at 2000 rev/min.

a) Assume uniform pressure (new clutch)

b) Assume uniform wear (old clutch), and find the pressure on the lining.

 

 

T = μ F_s n r_m ,

P = T [2π N /(60 x 1000)]

 

Where:

          T = engine torque (N m)

          μ = coefficient of friction

          F_s = spring force (N)

          n = number of friction surface (2 x number of friction plates)

          r_m = mean friction radius (m)

          P = power (kW)

          N = rev/min (1/min)