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Hydraulic finger-like lifter is made up of cylinder, plunger, ball piston, check valve, return spring, etc. The oil pressure controls opening and closing of check valve and further controls relative displacement of ball piston and plunger, realizing automatic compensation of valve lash. It is usually matched with rocker arms for use, and the radius of ball head of the ball piston is slightly smaller than that of ball socket of rocker arms, forming wedge-shaped oil film to lubricate the ball head and ball socket. Hydraulic finger-like lifter has automatic length compensating thermal expansion, realizing zero lash and reducing noise and impact.