Patent ID: 7392773

Claim:
A lift-variable valve-operating system for an internal combustion engine, comprising: a control arm ( 117 ) which is swingably supported in an engine body ( 111 ) through support shaft portions ( 116 ) provided on a pair of sidewalls ( 127 ), respectively; a plurality of rocker arms ( 122 ) which are swingably supported on spherical surfaced bearings ( 131 a ) between the pair of sidewalls ( 127 ) of the control arm ( 117 ) and which abut against engine valves ( 112 ); and a subsidiary cam ( 121 ) which is swingably supported between the pair of sidewalls ( 127 ) and which is driven by a valve-operating cam ( 114 ) to drive the rocker arm ( 122 ), the control arm ( 117 ) being rotated about the support shaft portions ( 116 ) by an actuator ( 150 ) to change at least a valve lift of the engine valves ( 112 ), the control arm ( 117 ) including a bulkhead ( 130 ) between the adjacent rocker arms ( 122 ) so as to prevent falling of the rocker arms ( 122 ).