Semi Centrifugal clutch

                                                 Semi Centrifugal clutch


 Disadvantages of centrifugal clutch

 •Automatically disengaging at low engine speeds

 •Only at high speeds, centrifugal force is sufficient to keep the clutch in engaged position

 Semi centrifugal clutch:

 •Springs are designed to transmit the torque at lower engine speeds 

 •Centrifugal force assists in torque transmission at higher engine speeds

 Construction details of semi centrifugal clutch:

 

  •Three hinged and weighted levers and three clutch 

    springs alternately arranged at equal space on the 

    pressure plate(only one lever and clutch spring shown in figure) 

  •Fly wheel is fitted to engine crank shaft 

  •Clutch plate is mounted on the splines of the clutch shaft 

  •Pressure plate is freely supported on clutch shaft 

  Working of Semi centrifugal clutch

  Clutch engaged 

  •Clutch springs exerts pressure on pressure plate at low 

    engine speeds 

  •At high speeds the centrifugal force developed by rotation of weighted levers exerts 

   pressure on pressure plate

  •Pressure plate applies pressure on clutch plate 

  •Clutch plate firmly rotates in between fly wheel and pressure plate 

  •Clutch shaft rotates along with clutch plate

  Clutch disengage 

  •As Driver presses the clutch pedal, pressure plate moves back against the force of the  

   springs 

  •Clutch plate also moves back on splines of clutch shaft 

  •Clutch plate speed reduces slowly and finally stops

  Advantages of semi centrifugal clutch:

  •Less stiff clutch springs are used as they operate only at low speeds 

  •Driver will not get strained in operating the clutch

  Used in 

  •Vauxhall car (foreign car)