Lyon & Lyon
Hydraulic clutch construction
 A hydraulic clutch (40) for u se in an automotive automatic transmission includes a clutch drum (41) having a hydraulic pressure chamber (43), a piston (42) movably fitted in the clutch drum (41) in covering relation to the hydraulic pressure chamber (43), a pressure plate (45) disposed in confronting relation to a surface of the piston (42) remotely from the hydraulic pressure chamber (43), and interleaved drive and driven plates (46, 47) disposed in confronting relation to a surface of the pressure plate (45) remotely from the piston (42). The drive and driven plates (46, 47) are engageable with each other by the pressure plate (45) pressed by the piston (42) moved in response to a hydraulic pressure supplied to the hydraulic pressure chamber (43). An assisting member (44) is disposed between the piston (42) and the pressure plate (45) and comprises an annular array of rigid assisting levers (44a) and a retaining plate (44b) holding the assisting levers (44a) together. The assisting member (44) has a radially inner and pressable by the piston (42), a radially outer end held in engagement with the clutch drum (41), and a radially intermediate region engageable with a projection (45a) of the pressure plate (45). The assisting lever serves (44a) as a lever with the radially outer end as a fulcrum for boosting the force applied from the piston (42) and transmitting the boosted force to the pressure plate (45). 
Honda Giken Kogyo Kabushiki Kaisha
F
F16D
inventional
Shigeo Yasuyuki Hiroshi
Ozawa Suzuki Nakayama