VALVE DRIVE CAM Russian patent published in 1999 - IPC

FIELD: mechanical engineering; valve gears of internal combustion engines. SUBSTANCE: curve of second derivative of tappet motion by angle of turn of cam forming its profile consists of positive magnitude section 1, 2 and negative magnitude section 3, 4. sections are made in form of piecewise linear functions of angle of turn of cam containing final number of lengths at preset initial conditions at the beginning of positive magnitude section 1, 2 and at the end of negative magnitude section 3, 4. Magnitudes of second derivative at points of joints of adjacent sections are maximum by modulus at limitations for derivatives of second and higher orders taking into account the fact that magnitude of second derivative is equal to preset value at preset magnitude of angle of turn of cam (point 5 in Fig.) in positive magnitude section. EFFECT: dynamic adjustment of cam on basis of forming positive magnitude section having two maxima. 1 dwg