Friction clutch

Claim 1

For attachment to a rotary torque-transmitting element, such as a flywheel, a pull-type friction clutch, comprising a diaphragm spring having an annular main section constituting or forming part of a first conical frustum, alternating tongues and slots extending inwardly from said main section, prongs extending outwardly from said main section and arranged to be secured to the torque-transmitting element, said prongs constituting or forming part of a second conical frustum, openings disposed between the slots and the prongs, as considered in the radial direction of the spring, and intermediate portions disposed in the region of said openings and constituting torsion zones between said conical frusta to facilitate changes of the conicity of said first conical frustum with reference to the conicity of said second conical frustum; a pressure plate movable axially of the torque-transmitting element under or against the bias of said spring when said prongs are secured to the torque-transmitting element; and a clutch disc adjacent to said pressure plate and arranged to be biased by the latter when the prongs of said spring are secured to the torque-transmitting element and said pressure plate is biased by said spring, said spring having a portion disposed inwardly of said prongs and arranged to bias said pressure plate toward said clutch disc.